Soil-Water:Management-A1

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Adjuvants

Adjuvants, Applying Pesticides Correctly, EPA and USDA

An adjuvant is a chemical added to a pesticide formulation or tank mix to increase its effectiveness or safety. Most pesticide formulations contain at least a small percentage of adjuvants. Some of the most common adjuvants are surfactants -- "surface active ingredients" that alter the dispersing, spreading, and wetting properties of spray droplets.




Adjuvants, types of

Adjuvants, types of, Applying Pesticides Correctly, EPA and USDA

Wetting agents -- allow wettable powders to mix with water.

Emulsifiers -- allow petroleum-based pesticides (EC's) to mix with water.

Invert emulsifiers -- allow water-based pesticides to mix with petroleum carrier.

Spreaders -- allow pesticide to form a uniform coating layer over the treated surface.

Stickers -- allow pesticide to stay on the treated surface.

Penetrants -- allow the pesticide to get through the outer surface to the inside of the treated area.

Foaming agents -- reduce drift.

Thickeners -- reduce drift by increasing droplet size.

Safeners -- reduce the toxicity of a pesticide formulation to the pesticide handler or to the treated surface.

Compatibility agents -- aid in combining pesticides effectively.

Buffers -- allow pesticides to be mixed with diluents or other pesticides of different acidity or alkalinity.

Antifoaming agents -- reduce foaming of spray mixtures that require vigorous agitation.




Allergic effects statement

Allergic effects statement, Applying Pesticides Correctly, EPA and USDA

If tests or other data indicate that the pesticide product has the potential to cause allergic effects, such as skin irritation or asthma, the product labeling must state that fact. Sometimes the labeling refers to allergic effects as "sensitization."

Personal protective equipment statements -- Immediately following the statements about acute, delayed, and allergic effects, the labeling usually lists personal protective equipment requirements. These statements tell you the minimum personal protective equipment that you must wear when using the pesticide. Sometimes the statements will require different personal protective equipment for different pesticide handling activities. For example, an apron may be required only during mixing, loading or equipment cleaning. Sometimes the statements will allow reduced personal protective equipment when you use safety systems, such as closed systems or enclosed cabs.




Application

Application, Applying Pesticides Correctly, EPA and USDA

Every time you apply pesticides, you have two major responsibilities:

  • protecting yourself, others, and the environment, and
  • making sure that the pesticide is applied correctly.




Application Amount

Application Amount, Applying Pesticides Correctly, EPA and USDA

One of the most important tasks for a pesticide applicator is making sure that the correct amount of pesticide is being applied to the target site. Studies indicate that only one out of four pesticide applications is applied within an acceptable range of the intended rate. Applying either too little or too much pesticide can cause problems.

For each pesticide application, take the time to determine how much you need to apply. Then be sure that you apply the correct amount.

Underdosing is expensive. If you apply too little pesticide, you may not fully control the pest. Sometimes you can repeat the entire application, but that can be very costly in both time and money. In other cases, a repeat application may not be possible because it would result in an overdose.

Overdosing is expensive because of the high cost of pesticides. Do not use any more than the amounts listed in the Directions for Use section of the pesticide labeling. Using more product than the labeling recommends will not do a better job of controlling pests, and it is illegal. Overdosing may cause damage or injuries, leave illegal residues, and cause you to be fined or to be liable for damages.




Application Amount -- Calibration and Loading Needed, No Mixing

Application Amount -- Calibration and Loading Needed, No Mixing, Applying Pesticides Correctly, EPA and USDA

Ready-to-use formulations sometimes must be loaded into equipment that does require calibration. These include most granular and dust formulations, some liquid formulations (especially solutions), and some fumigant formulations. The pesticide is loaded directly into application equipment without any further dilution. The equipment must be calibrated so that the correct amount of pesticide will be released per unit area.




Application Amount -- Calibration, Mixing, and Loading Needed

Application Amount -- Calibration, Mixing, and Loading Needed, Applying Pesticides Correctly, EPA and USDA

Many concentrated pesticides are applied with equipment that must be calibrated. For many certified applicators, this is the option most commonly encountered. The concentrate must be diluted correctly and the equipment must be calibrated correctly. Both steps are crucial to applying the correct amount of pesticide to a target site. If there is an error either in dilution or in calibration, the wrong amount of pesticide will be applied.




Application Amount -- Deciding How Much To Apply

Application Amount -- Deciding How Much To Apply, Applying Pesticides Correctly, EPA and USDA

Study the Directions for Use section of the pesticide labeling to find out how much pesticide you should apply. If the labeling lists a range of possible amounts, use the least amount that will achieve good control. Sometimes consultants, industry organizations, pest or pesticide specialists, Cooperative Extension agents, university specialists, or pesticide dealers will recommend appropriate amounts.

The amount of pesticide to use is expressed in various ways. Application rates may be expressed in terms of how much pesticide formulation should be applied. The instructions may tell you how much pesticide formulation should be applied to each unit of area or volume in the target site -- 5 gallons of formulation per acre, or 1 pound of formulation per 100 cubic feet of space, for example. Application rates also may be expressed in terms of how much pesticide formulation should be used per volume of mixture. Labeling might call for 3 tablespoons of product per 5 gallons of water or 1 pint of product per 100 gallons of water.

Sometimes pesticide labeling and other sources express application rates in terms of how much active ingredient should be applied per unit of area or per volume of mixture -- 1 pint active ingredient per 1,000 square feet, or 1/2 pound active ingredient per 500 gallons of water, for example. When the application rate is expressed in this way, you can select different formulations and be able to figure how much to dilute each one. However, figuring the correct dilution for active ingredient recommendations is more complicated.

Occasionally the application rate is expressed in terms of a percentage of the final dilution -- 1/2 percent by volume or 1 percent by weight, for example. Products that are adjuvants often express the application rate in this way. Expressing application rate as a percentage allows the user to calculate the dilution correctly for whatever dilution method is being used for the formulation.




Application Amount -- Loading Needed, No Mixing or Calibration

Application Amount -- Loading Needed, No Mixing or Calibration, Applying Pesticides Correctly, EPA and USDA

Some ready-to-use pesticides are not sold in the pesticide application equipment. The user must load them into the equipment. If the application equipment to be used is a squeeze-trigger sprayer, shaker-can duster, a vat for dipping animals or plants, a spray-dip vat, a wiper applicator, or some fumigant applicators, no calibration is necessary.




Application Amount -- Mixing and Loading Needed, No Calibration

Application Amount -- Mixing and Loading Needed, No Calibration, Applying Pesticides Correctly, EPA and USDA

Some concentrated pesticides are diluted and then loaded into equipment that does not require calibration. Many plant and animal dips or spray-dips, tree-canopy sprays, and crack and crevice treatments are applied by equipment that does not need calibration. The applicator is instructed to "cover the plant, animal, or surface thoroughly" or "apply to the point of runoff."




Application Amount -- Mixing, Loading, and Calibration Alternatives

Application Amount -- Mixing, Loading, and Calibration Alternatives, Applying Pesticides Correctly, EPA and USDA

Knowing what amount of the pesticide you must apply is only the first step. Next, you must determine how you will deliver the correct amount to the target site. Depending on the type of formulation you choose and the type of application equipment you will use, you may have to do some combination of three basic tasks -- mixing the pesticide, loading it into your equipment, and calibrating the equipment so you will know exactly how much pesticide it is delivering.

  • Mixing -- Unless the pesticide is a ready-to-use formulation or is designed to be applied full strength, you must carefully combine the right amounts of concentrated pesticide formulation and diluent to make the needed application-strength pesticide mixture.
  • Loading -- You may need to transfer the pesticide into the equipment before it can be applied.
  • Calibrating -- For many kinds of applications, you must measure and adjust the amount of pesticide your equipment will apply to the target site.

Each different combination of formulation and equipment type requires you to do a different combination of these tasks to prepare for applying a measured amount of pesticide.




Application Amount -- No Calibration, Mixing, or Loading Needed

Application Amount -- No Calibration, Mixing, or Loading Needed, Applying Pesticides Correctly, EPA and USDA

Some pesticide formulations are sold at application strength and are already in the equipment needed for application. These include aerosol cans; squeeze-trigger sprayers; delayed-trigger foggers; baits; shaker-can dusters; impregnated collars, bars, strips, and rollers; and wiper bags. The pesticide may be applied to the point of runoff, directed at a specific target, placed so the target contacts it, or released to fill an enclosed space. Most of these pesticides are available for use in only a few specialized pest control situations.




Application Amount, Calculation -- Application Rate

Application Amount, Calculation -- Application Rate, Applying Pesticides Correctly, EPA and USDA

The amount of pesticide dispersed, divided by the distance covered, is the application rate. Sometimes no calculations are needed. If, for example, the label lists the application rate as "per acre" or "per 1,000 linear feet" and you measure the output for exactly 1 acre or exactly 1,000 linear feet, no calculations are necessary because the amount of output you measured is the amount required.

However, you may not have time to test your equipment over such a large site. Or, if you are using the actual pesticide in the test, you may not want to risk applying it over a large site without knowing the application rate. Under these conditions, test smaller sites and then calculate the application rate.


Small equipment, small target sites

If your application equipment carries a relatively small load (up to a few gallons of liquid or a few pounds of dry pesticide) or if the target site is relatively small (less than an acre or 1,000 linear feet), you can choose a small test site.

If the use directions are for 100 linear feet, choose a test site of 25 linear feet. If the directions are for 1,000 square feet or for an acre, you might choose a test site of 250 square feet (a 10- by 25-foot rectangle). Measure the amount applied in this smaller site and then multiply to find the rate:

  • The amount applied to 25 linear feet, multiplied by 4, equals the rate per 100 linear feet.
  • The amount applied to 250 square feet, multiplied by 4, equals the rate per 1,000 square feet.
  • The amount applied to 250 square feet, multiplied by 175, equals the rate per acre.


Larger equipment, larger target sites

If your application equipment carries a larger load (more than a few gallons of liquid or a few pounds of dry pesticide) or if the target site is relatively large (greater than an acre or 1,000 linear feet), choose a larger test site. If the test site for these types of equipment or sites is too small, measurements are likely to be inaccurate. Operating a boom or other multi-nozzle or multi-hopper equipment over a site as small as 10 feet by 25 feet, for example, would not allow you to carry or drive the equipment far enough to gauge average speed accurately.

If label directions are for 1,000 square feet or for an acre, use a test site of at least 1,000 square feet (a 20- by 50-foot rectangle). The output you measure during the test will be the actual application rate for the 1,000 square feet. To find the rate per acre, multiply the test output by 43.56, which is the number of square feet in an acre (43,560) divided by 1,000.




Application Amount, Calculation -- Check Calibration Often

Application Amount, Calculation -- Check Calibration Often, Applying Pesticides Correctly, EPA and USDA

Once you have calibrated your equipment, do not assume that it will continue to deliver the same rate during all future applications. Clogging, corrosion, and wear may change the delivery rate, or the settings may gradually get out of adjustment. Take time to check the calibration regularly.

Be alert for possible calibration problems each time you use application equipment. During the application, notice whether you are treating the same amount of area per load that you figured. If you find that you are covering more or less area, stop the application and check your figures and your equipment. If you have figured wrong or if your application equipment changes its delivery rate, you will be able to catch the mistake before you have a major problem.




Application Amount, Calculation -- Determining Size of Target Site

Application Amount, Calculation -- Determining Size of Target Site, Applying Pesticides Correctly, EPA and USDA

If the target site is a rectangle, circle, or triangle, you can use simple measurements and formulas to determine its size. Irregularly shaped sites often can be reduced to a combination of rectangles, circles, and triangles. Calculate the area of each and add them together to obtain the total area.

To apply fumigants and a few other pesticides to fill the entire inside of a structure or other enclosed space, you must calculate the volume (cubic feet) of the building, greenhouse, truck, railroad car, or ship hold. To apply pesticides to bodies of water (not just the surface), you must calculate the volume of the water in the pond or lake. Sometimes the structures or bodies of water are regular in shape. The calculations for these are fairly simple. If the structure or body of water is irregular, you must calculate parts of the structure separately and add them together to find the total volume.




Application Amount, Calculation -- Diluting Pesticides Correctly

Application Amount, Calculation -- Diluting Pesticides Correctly, Applying Pesticides Correctly, EPA and USDA

Some pesticides are dilute formulations sold at application strength. These often are labeled "Ready-To-Use" or "RTU." Many of the pesticide formulations are concentrates sold at strengths many times those needed for application. These formulations, which are usually powders or liquids must be diluted before use. Granules and dusts are rarely sold as concentrates; fumigants and ultra-low-volume formulations are concentrates that are applied full strength.

The person who prepares the pesticide mixture for application must figure carefully how much concentrated pesticide to use and how much diluent to add to the concentrate. Unless the pesticide is diluted correctly, the wrong amount of pesticide may be applied.

Water is the most common diluent in pesticide mixtures. Others include other liquids, such as kerosene and oil, and dry ingredients, such as corn husks and powders. Concentrated pesticides are either diluted in a "mix tank" and then loaded into the application equipment or loaded directly into the application equipment and diluted there.

The pesticide labeling or other recommendations will tell you:

  • what to use to dilute the formulation,
  • how much to use to dilute the formulation, and
  • how much of the dilute pesticide to apply per unit of area.

After determining how much you need to dilute the pesticide concentrate, calculate how much pesticide and diluent to combine to achieve the correct amount of dilute pesticide mixture in your application equipment. Depending on the situation, you may need to know:

  • how much your equipment holds when full or how much mixture you will need to complete the job,
  • how much mixture your equipment applies per unit of area,
  • the size of the site you need to treat.

Guides from many sources contain formulas and examples to help you make necessary calculations.

Pesticide labels express the desired dilution for the pesticide mixture in a variety of ways, depending on the type of product and the primary intended uses. If your application situation is not the same as those on which the labeling directions were based, you may have to use some simple arithmetic to convert the quantities to different units of measure.




Application Amount, Calculation -- Measure Accurately

Application Amount, Calculation -- Measure Accurately, Applying Pesticides Correctly, EPA and USDA

When you measure pesticides or diluents, measure accurately. Inaccurate measurements can lead to underdosing, overdosing, too much pesticide mixture left in the tank, or a tankload of the wrong strength of pesticide mixture.

  • Use graduated utensils. If you are measuring a dry formulation, use a scale to weigh out the exact number of pounds or ounces you need. If you are measuring a liquid formulation or diluent:
  • use measuring spoons or a "tip and pour" to measure teaspoons or tablespoons,
  • use a graduated measuring cup or a "tip and pour" to measure from 1/4 cup to 1 pint,
  • use a graduated jug or pail to measure from 1 pint to 5 gallons,
  • use a flow meter to measure more than 5 gallons at a time.

Carefully measure the amount of pesticide to add. Do not guess how much you are adding and do not add a little extra "just to be sure." Also measure the amount of diluent carefully. Adding the correct amount of concentrate to an approximated amount of diluent can result in a whole tankful of the wrong strength of pesticide mixture. Mix only the amount you have calculated is needed for the application.

Do not assume that the tank is exactly the size of its claimed capacity. A "5 gallon" tank may hold more or less than 5 gallons. A "100 gallon" tank often holds quite a bit more than 100 gallons when totally filled. Measure the tank yourself to be sure. Even the graduated marks on some tanks or hoppers that indicate levels of partial fill are often inaccurate.

You can measure the capacity of your tank and check (or make) gauges indicating partial fill levels in two ways. You can fill the tank by hand using a container of known capacity, such as a measuring cup for small tanks and a 5-gallon pail for larger tanks. Or you can attach a flow meter to a hose and measure the quantity of water as it flows into the tank. For either method, as you fill the tank, you should check or mark measured volumes on a dip stick or sight gauge.

If water or another liquid is being used to dilute the concentrate, rinse the measuring utensils with the diluent and put the rinsate into the mix tank. Repeat this three times to be sure all of the pesticide is removed from the measuring utensil. Measure the amount of a ready-to-use formulation carefully, too. Trying to put pesticide back into the container when you have too much left over after the application is often difficult. Add only the amount you have calculated is needed to complete the application job.

Measuring utensils, such as spoons, cups, jugs, pails and scales, that you use with pesticides should never be used for other purposes. Clean them thoroughly after each use and store them with other pesticide equipment.



Application Amount, Calibration

Application Amount, Calibration, Applying Pesticides Correctly, EPA and USDA

Most pesticide applications involve equipment that must be measured and adjusted to release the correct amount of pesticide to the target site. Proper calibration is an essential but often neglected task. To be sure your equipment is releasing the right amount of pesticide, take time to calibrate it carefully and correctly. Recheck it regularly to detect changes caused by wear, corrosion, and aging.

Calibration often requires some simple arithmetic. Usually the equipment manufacturer, the pesticide dealer, your industry organization, or the Cooperative Extension Service will provide some standard formulas to help you. The easiest and most accurate way to do the calculations is with a calculator.

Choose equipment that you know how to use and that is:

  • designed for the type of chemical being applied, and
  • appropriate for the size and type of application job.

Equipment will not deliver the right amount of pesticide to the target site if it is not working correctly. Before you begin to calibrate the equipment, check it carefully to be sure that all components are clean and in good working order. Pay particular attention to the parts that regulate the amount of pesticide being released, such as nozzles and hopper openings. If they become clogged, not enough pesticide will be released. If they become worn, too much pesticide will be released.

Equipment that must be calibrated includes mechanical dusters; granule spreaders; hand, backpack, boom, handgun, high-pressure, airblast, and most other sprayers; and fumigant applicators. The many types of application equipment differ in the details of their operation, but if you understand the basic principles of calibration, you can apply them in any situation.

Study the manufacturer's instructions carefully -- they explain exactly how to adjust the equipment. They often contain suggestions on such things as the appropriate rate of travel, the range of most efficient pump pressures, approximate settings for achieving various delivery rates, and types of nozzles that can be used.




Application Amount, Calibration Methods

Application Amount, Calibration Methods, Applying Pesticides Correctly, EPA and USDA

No matter what calibration method you use, you will be measuring how much pesticide is being applied in a specific area. Calibration usually requires you to operate the equipment over a pre-measured distance.

The rate of application depends partly on the particle or droplet size, texture, and other properties of the pesticide being applied, so you will need to decide what material to use in the test. If the pesticide is a liquid with water as the major diluent, use water alone in the test. If the pesticide is a dust, granule, or fumigant, or a liquid diluted with a liquid other than water, you must use the actual pesticide in the test.

The rate of application sometimes depends also on the pressure and on the nozzle size or hopper opening. The equipment manufacturer's directions are the best guide to these selections.




Application Amount, Calibration -- Equipment with gravity-flow dispersal

Application Amount, Calibration -- Equipment with gravity-flow dispersal, Applying Pesticides Correctly, EPA and USDA

If the equipment you have chosen uses gravity to maintain the flow of pesticide, calibration may be fairly simple. Some equipment, such as some granule spreaders, needs to be calibrated only to adjust the rate of flow or delivery. This equipment releases pesticide only when the wheels are in motion. If the equipment speed is kept at an even, moderate pace, the amount of pesticide being released per unit area will be uniform.




Application Amount, Calibration -- Equipment with powered dispersal

Application Amount, Calibration -- Equipment with powered dispersal, Applying Pesticides Correctly, EPA and USDA

If your equipment has a pump or other mechanism to disperse the pesticide, you will need to determine the rate of speed best suited for the type of equipment and for the particular requirements of your application job. Such equipment may be either hand-carried or mounted on a vehicle. In either case, the speed at which the equipment moves through the target site determines the amount of pesticide applied in a given area. Keep the speed as constant as possible during the calibration process and during the actual application. For the most accurate calibration, operate the equipment at the target site or on ground (or other surface) similar to that at the target site. Whether the equipment is hand-carried or mounted on a vehicle, the condition of the ground (surface) that must be crossed is important. A rough and uneven surface will cause the equipment to be operated at a slower speed.

The equipment manufacturer's directions may offer a range of appropriate speeds. Your knowledge of conditions in the target site (including the drift hazard), plus your experience with the equipment, will help you determine an appropriate speed.




Application Amount, Calibration -- Speed

Application Amount, Calibration -- Speed, Applying Pesticides Correctly, EPA and USDA

For some application equipment, the speed at which the equipment moves (or is carried) through the target site is one of the main factors determining application rate. For other equipment, speed is not a factor.




Application Amount, Calibration -- Test Application

Application Amount, Calibration -- Test Application, Applying Pesticides Correctly, EPA and USDA

Calibrate your application equipment by:

accurately measuring the amount in the tank or hopper;

operating the equipment over the pre-measured distance while maintaining your chosen speed (if speed affects the delivery rate of the equipment you are using); and

accurately measuring the amount needed to fill the tank or hopper back up to the pre-application level.

If multiple nozzles or hoppers are used, add the output of all the collection jars.




Application Amount, Calibration -- Uniform Release

Application Amount, Calibration -- Uniform Release, Applying Pesticides Correctly, EPA and USDA

If your application equipment has more than one nozzle (or more than one cluster of nozzles) or hopper, part of the calibration process is to measure the output from each to be sure that they are releasing a uniform amount of pesticide. First, check for clogging or obstructions, leaks, or worn nozzles. Then, measure the pesticide output for each nozzle (or cluster of nozzles) or hopper for a specific period of time. The output must be within 10 percent of the average of the nozzles (or cluster of nozzles) or hoppers. Finally, replace worn or damaged nozzles or hoppers if the output is beyond 10 percent of the average.

You can check for uniform output in two ways. Either method requires that you attach containers to collect the output from each nozzle, nozzle cluster, or hopper. The first method is to operate the equipment for a set period of time and compare the amount of output in each container to the amount desired. The second option is to operate the equipment over a measured area while calibrating the equipment and, at the end of the calibration run, compare the amount of output in each container to the amount desired. If all the nozzles or hoppers are intended to release an equal amount of pesticide, just check to see whether all the containers contain the same amount.




Application Equipment

Application Equipment, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

The pesticide application equipment you use is important to the success of your pest control job. First, you must select the right kind of application equipment; then you must use it correctly and take good care of it.

This unit provides an overview of some things you should know about choosing, using, and caring for equipment. To use your pesticide application equipment safely and effectively, study the manufacturer's directions carefully. Some pesticide applications -- such as airblast spraying, fumigation, aerial application, and chemigation -- are highly specialized. You will need special training to use the equipment these applications require.


Application Equipment for Animals , Bait Application Equipment -- Bait Stations

Application Equipment for Animals , Bait Application Equipment -- Bait Stations, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Bait stations hold pesticide-treated food that attracts target pests. They are used for insect control around poultry and livestock housing and for vertebrate control around crops, commodities, and agricultural buildings.


Application Equipment for Animals , Bait Application Equipment -- Bait Applicators

Application Equipment for Animals , Bait Application Equipment -- Bait Applicators, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Bait applicators are used to apply pesticides to control gophers, moles, and other underground vertebrate pests. Some hand-operated models inject the poisoned bait directly into underground burrows. Mechanical models are tractor-mounted machines that form artificial burrows that intersect with natural burrows. When the pests use the artificial burrows, they feed on the bait.


Application Equipment for Animals , Dipping Vats

Application Equipment for Animals , Dipping Vats, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Dipping vats are large tanks (vats) of liquid pesticide mixture used to treat livestock for external parasites. Portable dipping vats are usually trailer-mounted tanks with a set of folding ramps and railings. The animals are driven up the ramp onto a platform and forced into the tank so they are completely immersed. The animal's head may have to be pushed under the surface.


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Maintaining the proper concentration of pesticide in the vat is very important. The vat should be kept at least 7/8 full at all times. Replenishment is usually based on a knowledge of the amount of liquid removed from the vat.


Application Equipment for Animals , Dust Boxes

Application Equipment for Animals , Dust Boxes, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Dust boxes are used mainly in raised wire battery-type cages for laying hens or other poultry. These boxes contain a pesticide dust used to control poultry pests, usually mites. Birds wallow in the boxes and pick up the dust on their feathers and skin.


Application Equipment for Animals , Face and Back Rubbers and Dust Bags

Application Equipment for Animals , Face and Back Rubbers and Dust Bags, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Face and back rubbers and dust bags are containers of dry or liquid pesticide formulation used to control external parasites of livestock. The devices are hung or mounted in areas adjacent to high livestock traffic, such as feeding troughs, waterers, and narrow gate entrances. When the animal rubs against the device, the pesticide is transferred to the animal's face, back, sides, or legs.

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Application Equipment for Animals , Spray-Dip Machines

Application Equipment for Animals , Spray-Dip Machines, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Spray-dip machines are used to treat livestock for external parasites. A spray- dip machine usually consists of a trailer-mounted chute with solid walls and gates at either end. The chute is located above a shallow tank and is equipped with several rows of large nozzles mounted in a manner that directs the spray mixture to thoroughly cover each animal. A large centrifugal pump supplies the pesticide to the nozzle. Surplus and runoff spray falls back into the tank where it is filtered and recycled to the nozzles.


Application Equipment, Aerosol Generators and Foggers

Application Equipment, Aerosol Generators and Foggers, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA


Aerosol generators and foggers convert special formulations into very small, fine droplets (aerosols). Single droplets cannot be seen, but large numbers of droplets are visible as a fog or mist. Aerosol generators and foggers usually are used to completely fill a space with a pesticidal fog. Some insects in the treated area are killed when they come in contact with the poison. Other insects are simply repelled by the mist and return quickly after it has settled.

Thermal foggers, also called thermal generators, use heat to vaporize a special oil formulation of a pesticide. As the pesticide vapor is released into the cooler air, it condenses into very fine droplets, producing a fog.

Other aerosol generators (cold foggers) break the pesticide into aerosols by using mechanical methods such as:

  • rapidly spinning disks,
  • extremely fine nozzles and high pressure (atomizing nozzles),
  • strong blasts of air.

Advantages:

  • penetration in dense foliage,
  • penetration of cracks and crevices,
  • some indoor devices are automatic and do not require presence of applicator.

Limitations:

  • aerosols and fogs drift easily from target area,
  • no residual control -- pests may return to the area as soon as fog dissipates,
  • risk of explosion in enclosed areas.


Application Equipment, Aerosol Generators and Foggers -- Selection, Use, and Care

Application Equipment, Aerosol Generators and Foggers -- Selection, Use, and Care, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Choose an aerosol generator according to where you will use it -- indoors or outdoors. Aerosol and fog generators are manufactured for many special uses. There are truck- and trailer-mounted machines for use outdoors. Most hand-operated or permanently mounted automatic machines are for use indoors.

In general, use and care for an aerosol generator as you would a sprayer. They do require several special precautions, however:

  • Be sure that the pesticides used in the aerosol and fog generators are registered for that use.
  • Keep the pesticides on the target.
  • Because aerosol and fog formulations are easily affected by weather conditions during application, follow special use instructions.
  • The operator, other people, and animals should stay out of the fog or smoke cloud.


Application Equipment, Dusters

Application Equipment, Dusters, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Dusters are used only occasionally in outdoor agricultural situations, because of the high probability of drift. Dust applications are more common in greenhouses and other enclosed agricultural areas.


Application Equipment, Dusters -- Granule Applicators

Application Equipment, Dusters -- Granule Applicators, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Granule applicators distribute granular pesticides by several different methods, including:

  • forced air,
  • spinning or whirling disks (fertilizer spreaders),
  • multiple gravity-feed outlets (lawn spreaders, grain drills),
  • soil injectors (furrow treatments),
  • ram-air (agricultural aircraft).

Granule applicators may be designed to apply the pesticides:

  • broadcast -- even distribution over the entire area,
  • to specific areas -- banding, in-furrow, side-dress,
  • by drilling -- soil incorporation or soil injection.

Advantages:

  • simple in design,
  • eliminates mixing -- no water needed,
  • minimal drift hazard,
  • low exposure hazard to applicator.

Limitations:

  • limited use against some pests because granules will not adhere to most foliage,
  • need to calibrate for each different granular formulation,
  • spinning disk types may give poor lateral distribution, especially on side slopes.


Application Equipment, Dusters -- Hand dusters

Application Equipment, Dusters -- Hand dusters, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Hand dusters may consist of a squeeze bulb, bellows, tube, shaker, sliding tube, or a fan powered by a hand crank.

Advantages:

  • lightweight -- do not require water,
  • the pesticide is ready to apply without mixing,
  • good penetration in confined spaces.

Limitations:

  • dust may not stick to foliage,
  • dust is difficult to direct,
  • drift potential is high.


Application Equipment, Dusters -- Power dusters

Application Equipment, Dusters -- Power dusters, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Power dusters use a powered fan or blower to propel the dust to the target. They include knapsack or backpack types, units mounted on or pulled by tractors, and specialized equipment for treating seeds. Their capacity in area treated per hour compares favorably with some sprayers.

Advantages:

  • lightweight -- no water required,
  • simply built,
  • easy to maintain.

Limitations:

  • drift hazards,
  • application may be less uniform than with sprays,
  • dust may not stick to foliage.


Application Equipment, Dusters -- Selection, Use, and Care

Application Equipment, Dusters -- Selection, Use, and Care, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Look for a power duster that is easy to clean. It should give a uniform application rate as the hopper is emptied. Look for both hand and power dusters that direct the dust cloud away from the user.

Choose a granule applicator that is easy to clean and fill. It should have mechanical agitation over the outlet holes. This prevents clogging and helps keep the flow rate constant. Application should stop when drive stops even if outlets are still open.

Both dusters and granule applicators are speed-sensitive, so maintain uniform speed. Do not travel too fast for ground conditions. Bouncing equipment will cause the application rate to vary. Stay out of any dust created by action of the equipment.

Watch band applicators to see that band width stays the same. Small height changes due to changing soil conditions may cause rapid changes in band width. Clean equipment as directed by the operator's manual.


Application Equipment, Soil Fumigation Equipment

Application Equipment, Soil Fumigation Equipment, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

The equipment needed for applying soil fumigants depends on the kind of fumigant being used. There are two types of fumigants:

  • low-pressure (low volatility) liquid fumigants, and
  • highly volatile fumigants that remain as liquids only when placed under pressure.


Application Equipment, Soil Fumigation Equipment -- Drenching or flooding

Application Equipment, Soil Fumigation Equipment -- Drenching or flooding, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

These methods use water as a sealant. The fumigant may be applied in the water as a drench. The equipment needed depends on the size and timing of the application. The fumigant-containing water may be applied with a sprinkling can, sprinkler system, or irrigation equipment.

Another way to apply the fumigant is to first spray the pesticide on the soil surface and then immediately flood the area. The depth of the water seal (usually 1/2 to 4 inches of wetted soil) depends on the volatility of the fumigant.


Application Equipment, Soil Fumigation Equipment -- High-Pressure Fumigators

Application Equipment, Soil Fumigation Equipment -- High-Pressure Fumigators, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Effective application of highly volatile fumigants depends on tightly sealing the soil with tarps, plastic film, or similar covers. There are two major methods of using vapor-proof tarps:

  • Tarp supported off the ground and sealed around the edges; fumigant introduced under the tarp.
  • Tarp applied to the soil by the injection chisel equipment immediately after the fumigant is injected.

Highly volatile fumigants must be handled in pressurized containers or tanks. The equipment is similar to gravity-flow low-pressure fumigators. The pressure in the tank maintains the line pressure to the nozzle orifices.

The tank is either pre-charged with enough pressure to empty its contents, or an inert pressurized gas is fed into the tank during application to displace the fumigant. A gas regulator maintains uniform pressure in the system. To ensure accurate application, the fumigant must be under enough pressure to maintain a liquid state in the tank, pressure lines, manifold, and metering devices.


Application Equipment, Soil Fumigation Equipment -- Low-Pressure Liquid Fumigators

Application Equipment, Soil Fumigation Equipment -- Low-Pressure Liquid Fumigators, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Equipment for applying low-pressure fumigants varies widely, but uses two basic designs for metering and delivering the fumigant. These delivery systems are either pressure (pump)-fed or gravity-fed.

Pressure-fed applicators have a pump and metering device and deliver fumigant under pressure to the nozzle openings (orifices) as with a low-pressure sprayer.

Gravity-flow applicators use the size of the nozzle orifice and the pressure created by gravity to regulate the output of fumigant. Constant speed is necessary to maintain a uniform delivery rate. Most applicators have a device that keeps the pressure at the orifice constant as the tank or container of fumigant empties. Needle valves, orifice plates or disks, and capillary tubes are used to adjust the flow rate.

Low-pressure fumigators usually use the soil itself or water to keep the fumigant from vaporizing and moving off target too quickly. Some of the methods used are:

  • soil injection,
  • soil incorporation,
  • drenching or flooding.


Application Equipment, Soil Fumigation Equipment -- Selection of

Application Equipment, Soil Fumigation Equipment -- Selection of, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Pumps, tanks, fittings, nozzles or metering orifices, and lines must be corrosion resistant. Soil injection knives should be designed to shed crop residues and allow the soil to seal over the fumigant. Choose high-pressure fumigators designed to handle both the pressure created by the fumigant and the corrosive action of the product you plan to use.


Application Equipment, Soil Fumigation Equipment -- Soil incorporation

Application Equipment, Soil Fumigation Equipment -- Soil incorporation, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Soil incorporators are used when applying low-volatility fumigants. The fumigant usually is sprayed onto the soil surface. The area is immediately cultivated, usually to a depth of 5 inches or less, to incorporate the fumigant. Then the soil is compacted with a drag, float, or cultipacker. Power-driven rotary cultivators are also used.


Application Equipment, Soil Fumigation Equipment -- Soil injection

Application Equipment, Soil Fumigation Equipment -- Soil injection, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Soil injectors use a variety of mechanisms to insert the fumigant into the soil (usually at least 6 inches deep) and then cover the area with soil to seal in the fumigant. The principal mechanisms include chisel cultivators, blades, or shovels; sweep cultivator shovels; planter shoes; and plows.


Application Equipment, Specialized Application Equipment

Application Equipment, Specialized Application Equipment, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

You may sometimes use other types of equipment that is designed for specialized applications. Some of this specialized equipment is intended for application of herbicides. Other specialized application equipment is for applying pesticides through irrigation or watering systems.

Specialized Application Equipment for Herbicides

Some application equipment is designed to apply herbicides so that the herbicide contacts the weeds, but does not contact desirable plants in the treated area. This equipment includes:

  • recirculating sprayers,
  • shielded applicators,
  • wiper applicators,
  • wax bar applicators.


Application Equipment, Specialized Application Equipment -- Irrigation Application Equipment

Application Equipment, Specialized Application Equipment -- Irrigation Application Equipment, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Irrigation or watering systems can be equipped to deliver pesticides to a target. Known as "chemigation," this is a common method for applying pesticides in many irrigated areas. Accurate calibration and distribution are achieved by metering a large volume of dilute pesticide into the irrigation system. Antisiphon check valves prevent contamination of the irrigation water source and switch valves prevent overflow into the slurry feed tank.

Advantages:

  • convenient,
  • field access unnecessary.

Limitations:

  • constant agitation needed in slurry tank,
  • application of more water per acre than recommended on label will cause some pesticides to leach,
  • sprinkler distribution must have appropriate overlap pattern for uniform delivery,
  • injection of pesticides into flood and furrow irrigation systems may result in uneven concentrations of pesticides throughout the field, depending on soil permeability and field contours.



Application Equipment, Specialized Application Equipment -- Recirculating sprayers

Application Equipment, Specialized Application Equipment -- Recirculating sprayers, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

These devices usually are used to apply contact herbicides to weeds that are taller than the crop in which they are growing. Solid streams of highly concentrated herbicides are directed across rows above the crop. The system prevents the herbicide from contacting the desirable plants. Spray material that is not intercepted by the weeds is caught in a box or sump on the opposite side of the row and is recirculated. Advantages:

  • uses small quantities of pesticide,
  • less pesticide moves off target and into environment,
  • permits treatment of weeds that have escaped other control measures,
  • protects susceptible nontarget plants from injury.

Limitations:

  • use limited to special situations.


Application Equipment, Specialized Application Equipment -- Shielded applicators

Application Equipment, Specialized Application Equipment -- Shielded applicators, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

These applicators direct the herbicide onto the weeds while shielding desirable plants from the herbicide.


Application Equipment, Specialized Application Equipment -- Wax bars

Application Equipment, Specialized Application Equipment -- Wax bars, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Herbicides are sometimes applied with wax bars that are impregnated with herbicides. The bars are dragged slowly over the area to be protected.

Advantages:

  • no drift,
  • no calibration.

Limitations:

  • highly specialized, not readily available.


Application Equipment, Specialized Application Equipment -- Wiper applicators

Application Equipment, Specialized Application Equipment -- Wiper applicators, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Sometimes called "wick" or "rope" applicators, these devices are used to apply herbicides selectively to weeds in crop areas. Wicks made of rope, rollers made of carpet or other material, or absorbent pads made of sponges or fabric are kept wet with a concentrated mixture of herbicide and water and brought into direct contact with weeds. The herbicide is "wiped" onto the weeds, but does not come in contact with the crop.

Application may be to tall weeds growing above the crop or to lower weeds between rows, depending on the way the wiper elements are designed. Pumps, control devices, and nozzles are minimal or are eliminated altogether, and tanks are quite small because of the small amount of liquid applied.

Advantages:

  • simple to operate,
  • no drift,
  • uses small amount of pesticide.

Limitations:

  • useful only in special situations,
  • difficult to calibrate.


Application Equipment, Sprayers

Application Equipment, Sprayers, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Sprayers are the most common pesticide application equipment. They are standard equipment for nearly every pesticide applicator and are used in every type of pest control operation. Sprayers range in size and complexity from simple, hand-held models to intricate machines weighing several tons.


Application Equipment, Sprayer -- Selection, Use, and Care

Application Equipment, Sprayer -- Selection, Use, and Care, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Choosing the correct sprayer for each job is important. Your sprayer should be:

  • designed to do the job you want to do,
  • durable,
  • convenient to fill, operate, and clean.

Always read and follow the operator's manuals. They will tell you how to use and care for your spray equipment. After each use, rinse the entire system. Check for leaks in lines, valves, seals, and tank. Remove and clean nozzles, nozzle screens, and strainers.

Be alert for nozzle clogging and changes in nozzle patterns. If nozzles clog or other trouble occurs in the field, be careful not to contaminate yourself while correcting the problem. Shut off the sprayer and move it to the edge of the field before dismounting. Wear personal protective equipment while making repairs. Clean clogged nozzles only with a non-metal nozzle-cleaning tool. Sharp metal can ruin the nozzle. Never use your mouth to blow out a nozzle.

To prepare spray equipment for storage, follow manufacturer's instructions. If there are no instructions, rinse and clean the system. Then fill the tank almost full with clean water. Add a small amount of new lightweight oil to the tank. Coat the system by pumping this mixture out through the nozzles or handgun. Drain the pump and plug its openings or fill the pump with lightweight oil or antifreeze. Remove nozzles and nozzle screens and store in lightweight oil or diesel fuel.



Application Equipment, Sprayer Parts -- Agitators, Bypass

Application Equipment, Sprayer Parts -- Agitators, Bypass, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Bypass agitation uses the returning liquid from the pressure relief valve to agitate the tank. The return must extend to the bottom of the tank to prevent excessive foaming. Bypass agitation is sufficient for soluble powders and for liquid formulations such as solutions and emulsifiable concentrates that do not require much agitation.

Do not use bypass agitation for wettable powders or in tanks larger than 55 gallons, unless the system has a centrifugal pump. Centrifugal pumps usually have large enough outputs to make bypass agitation adequate even for wettable powders in tanks less than 100 gallons.


Application Equipment, Sprayer Parts -- Agitators, Hydraulic (jet action)

Application Equipment, Sprayer Parts -- Agitators, Hydraulic (jet action), Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Hydraulic agitation is provided by the high-pressure flow of surplus spray material from the pump. Hydraulic agitation is required for wettable powder and flowable formulations in small tanks and for liquid formulations in 100-gallon or larger tanks with gear, roller, piston, or diaphragm pumps.

The jet or jets for a hydraulic agitator are located at the bottom of the tank. The agitator is connected to the pressure side of the pump. Never place jet agitator nozzles in the bypass line.

The pump and tank capacity and operating pressure determine the minimum number of jets:

  • 55 gallons= 1 or more jets,
  • 100 to 150 gallons= 3 or more jets,
  • 200 gallons and larger= 5 or more jets.


Application Equipment, Sprayer Parts -- Agitators, Mechanical

Application Equipment, Sprayer Parts -- Agitators, Mechanical, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Wettable powder formulations are best mixed and kept in suspension with mechanical agitation. The mechanical agitator usually consists of flat blades or propellers mounted on a shaft that is placed lengthwise along the bottom of the tank. The paddles or propellers are rotated by the engine to keep the material well mixed. Mechanical agitators are usually found only on large high-pressure hydraulic sprayers.


Application Equipment, Sprayer Parts -- Agitators

Application Equipment, Sprayer Parts -- Agitators, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Every sprayer must have agitation to keep the spray material uniformly mixed. If there is too little agitation, the pesticide will be applied unevenly. If there is too much agitation, some pesticides may foam and interfere with pump and nozzle operation. The type of agitation needed depends on the pesticide formulation.


Application Equipment, Sprayer Parts -- Control Valves

Application Equipment, Sprayer Parts -- Control Valves, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Quick-acting cutoff valves should be located between the pressure regulator and the nozzles to provide positive on-off action. These control valves should be rated for the pressures you intend to use and should be large enough not to restrict flow when open. Cutoff valves to stop all flow or flow to any section of the spraying system should be within easy reach of the sprayer operator.

There are many kinds of control valves. Mechanical valves must be accessible to the operator's hand; electrically operated valves permit remote control of flow. For tractors or self-propelled sprayers with enclosed cabs, remote-controlled valves permit all hoses carrying pesticides to be kept safely outside the cab.


Application Equipment, Sprayer Parts -- Hoses

Application Equipment, Sprayer Parts -- Hoses, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Select neoprene, rubber, or plastic hoses that:

  • have burst strength greater than the peak operating pressures,
  • have a working pressure at least equal to the maximum operating pressure,
  • resist oil and solvents present in pesticides,
  • are weather resistant.

Suction hoses should be reinforced to resist collapse. They should be larger than pressure hoses, with an inside diameter equal to or larger than the inlet part of the pump. All fittings on suction lines should be as large as or larger than the inlet part of the pump.

Keep hoses from kinking or being rubbed. Flush hoses after use and wash them often to prolong life. During the off-season, store the sprayer out of the sun. Replace hoses at the first sign of surface deterioration (cracking or checking).


Application Equipment, Sprayer Parts -- Large Tanks

Application Equipment, Sprayer Parts -- Large Tanks, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Tanks should have large openings for easy filling and cleaning. Tanks should be designed to allow the use of strainers during filling, and also should allow mechanical or hydraulic agitation devices to be installed. The tank should be made of corrosion-resistant material such as stainless steel or fiberglass. If made of mild steel, it should have a protective lining or coating.

The tank should have a large drain, and other outlets should be sized to the pump capacity. If you use dual tanks, make sure the plumbing allows both tanks to have agitation and adequate withdrawal rates. All tanks should have a gauge to show the liquid level. External gauges should be protected to prevent breakage. All tanks should have a shutoff valve for storing liquid pesticide temporarily while other sprayer parts are being serviced.


Application Equipment, Sprayer Parts -- Nozzle Materials

Application Equipment, Sprayer Parts -- Nozzle Materials, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Most nozzle parts are available in several materials. Here are the main features of each kind:

  • Brass:

o resists corrosion from most pesticides,

o wears quickly from abrasion,

o probably the best material for general use,

o may be corroded by liquid fertilizers.

  • Plastic:

o will not corrode,

o resists abrasion better than brass,

o may swell when exposed to some solvents,

o useful life about equal to that of brass nozzles.

  • Stainless steel:

o resists abrasion, especially if hardened,

o good corrosion resistance,

o suited for high pressures, especially with wettable powders,

o lasts longer than brass.

  • Aluminum:

o resists some corrosive materials,

o easily corroded by some fertilizers,

o useful life much shorter than brass.

  • Tungsten carbide and ceramic:

o highly resistant to abrasion and corrosion,

o best material for high pressures and wettable powders,

o lasts much longer than brass.


Application Equipment, Sprayer Parts -- Nozzle, Cone pattern

Application Equipment, Sprayer Parts -- Nozzle, Cone pattern, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Hollow and solid cone patterns are produced by several types of nozzles. These patterns are used where penetration and coverage of plant foliage or other irregular targets are desired. They are most often used to apply fungicides and insecticides to foliage, although some types are used for broadcast soil applications of herbicides or fertilizers or combinations of the two.

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When cone pattern nozzles are used for airblast sprayer broadcast application, they should be angled to spray between 15degrees and 30degrees from the horizontal and should be spaced at the top of the manifold so the spray pattern will overlap up to 100 percent. The side-entry hollow cone or "whirl-chamber" nozzle produces a very wide angle hollow cone spray pattern at very low pressures. It has a large opening and resists clogging. Because of the wide spray angle, the boom can be operated low, reducing drift. Spacing for double coverage and angling 15degrees to 45degrees to the rear is recommended for uniform application. These nozzles may be used in place of flat fan nozzle tips in broadcast applications.

Core-insert cone nozzles produce either a solid or hollow cone spray pattern. They operate at moderate pressures and give a finely atomized spray. They should not be used for wettable powders because their small passages clog easily and they wear rapidly due to abrasion.

Disk-core nozzles produce a cone-shaped spray pattern, which may be hollow or solid. The spray angle depends on the combination of disk and core used and also, to some extent, on the pressure. Disks made of very hard materials resist abrasion well, so these nozzles are recommended for spraying wettable powders at high pressures.

Adjustable cone nozzles change their spray angle from a wide cone pattern to a solid stream when the nozzle collar is turned. Many manual sprayers are equipped with this type of nozzle. Handguns for power sprayers have adjustable nozzles that usually use an internal core to vary the spray angle.


Application Equipment, Sprayer Parts -- Nozzle, Fan pattern

Application Equipment, Sprayer Parts -- Nozzle, Fan pattern, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

At least three types of nozzle tips have fan patterns. They are used mostly for uniform spray coverage of surfaces; for example, broadcast soil applications of herbicides or insecticides.

The regular flat fan nozzle tip makes a narrow oval pattern with tapered ends. It is used for broadcast herbicide and insecticide spraying at 15 to 60 psi. The pattern is designed to be used on a boom and to be overlapped 30 to 50 percent for even distribution. Spacing on the boom, spray angle, and boom height determine proper overlap and should be carefully controlled.

The even flat fan nozzle makes a narrow oval pattern. Spray delivery is uniform across its width. It is used for band spraying and for treating walls and other surfaces. It is not useful for broadcast applications. Boom height and nozzle spray angle determine the width of the band sprayed.

The flooding (flat fan) nozzle delivers a wide-angle flat spray pattern. It operates at very low pressure and produces large spray droplets. Its pattern is fairly uniform across its width but not as even as the regular flat fan nozzle pattern. If used for broadcast spraying, it should be overlapped to provide double coverage. It is often used for applying liquid fertilizers or fertilizer-pesticide mixtures or for directing herbicide sprays up under plant canopies.

Cluster nozzles are used either without a boom or at the end of booms to extend the effective swath width. One type is simply a large flooding deflector nozzle that will spread spray droplets over a swath up to 70 feet wide from a single nozzle tip. Cluster nozzles are a combination of a center-discharge and two or more off-center-discharge fan nozzles.

The spray droplets vary in size from very small to very large. The small droplets may cause a drift problem. Coverage may be variable because the spray pattern is not uniform. Since no boom is required, these nozzles are particularly well suited for spraying hedgerows, fence rows, and other hard-to-reach locations where uniform coverage is not critical.


Application Equipment, Sprayer Parts -- Nozzle, Solid stream

Application Equipment, Sprayer Parts -- Nozzle, Solid stream, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

These nozzles are used in handgun sprayers to spray a distant or specific target such as livestock or tree pests.

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They also are used for crack and crevice treatment in and around buildings. Solid stream nozzles may be attached to booms to apply pesticides in a narrow band or inject them into the soil.


Application Equipment, Sprayer Parts -- Nozzles

Application Equipment, Sprayer Parts -- Nozzles, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Most nozzles have four major parts: the nozzle body [[thumbnails/pages/nozz1.htm"><IMG src="thumbnails/thumbnails/nozz1.jpg]], the cap [[thumbnails/pages/nozz2.htm"><IMG src="thumbnails/thumbnails/nozz2.jpg]], the strainer (screen) [[thumbnails/pages/nozz3.htm"><IMG src="thumbnails/thumbnails/nozz3.jpg]], and the tip or orifice plate [[thumbnails/pages/nozz4.htm"><IMG src="thumbnails/thumbnails/nozz4.jpg]].

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They also may include a separate spinner plate. Successful spraying depends on the correct selection, assembly, and maintenance of the nozzles.

The nozzle body holds the strainer and tip in proper position. Several types of tips that produce a variety of spray patterns may be interchanged on a single nozzle body made by the same manufacturer.

The cap is used to secure the strainer and the tip to the body. The cap should not be overtightened.

The nozzle strainer is placed in the nozzle body to screen out debris that may clog the nozzle opening. The type of nozzle strainer needed depends on the size of the nozzle opening and the chemical being sprayed.

Special nozzle screens equipped with a check valve help prevent nozzle dripping. Check valves should be used in situations where a sprayer must be stopped and started frequently, such as in small target areas, near sensitive crops or areas, indoors, or for right-of-way treatments. The operator must check these spring-loaded ball valves frequently to be sure they are working properly.

Nozzle tips break the liquid pesticide into droplets. They also distribute the spray in a predetermined pattern and are the principal element that controls the rate of application. Nozzle performance depends on:

  • nozzle design or type,
  • operating pressure,
  • size of the opening,
  • discharge angle,
  • distance of nozzle from the target.

Nozzle patterns are of three basic types: solid stream, fan, and cone. Some special-purpose nozzle tips or devices produce special patterns. These include "raindrops," "flooding," and others that produce wide-angle fan or cone-shaped patterns.


Application Equipment, Sprayer Parts -- Pressure Gauges

Application Equipment, Sprayer Parts -- Pressure Gauges, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Pressure gauges monitor the line pressure of your spraying system. They must be accurate and have the range needed for your work. For example, a 0 to 100 psi gauge with 2-pound gradations would be adequate for most low-pressure sprayers.

Check frequently for accuracy against an accurate gauge. Excess pressure will destroy a gauge. If yours does not zero, replace it. Use gauge protectors to guard against corrosive pesticides and pressure surges.


Application Equipment, Sprayer Parts -- Pressure Regulators

Application Equipment, Sprayer Parts -- Pressure Regulators, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

The pressure regulator controls the pressure and, indirectly, the quantity of spray material delivered by the nozzles. It protects pump seals, hoses, and other sprayer parts from damage caused by excessive pressure.

Keep the bypass line from the pressure regulator to the tank fully open and unrestricted. The bypass line should be large enough to carry the total pump output without excess pressure buildup. The pressure range and flow capacity of the regulator must match the pressure range you plan to use and the capacity of the pump. Never attach mechanical agitation devices to the bypass line discharge.

Pressure regulators are usually one of three types:

Throttling valves simply restrict pump output, depending on how much the valve is open. These valves are used with centrifugal pumps, whose output is very sensitive to the amount of restriction in the output line.

Spring-loaded bypass valves (with or without a diaphragm) open or close in response to changes in pressure, diverting more or less liquid back to the tank to keep pressure constant. These valves are used with roller, diaphragm, gear, and small piston pumps.

Unloader valves work like a spring-loaded bypass valve when the sprayer is operating. However, when the nozzles are shut down, they reduce strain on the pump by moving the overflow back into the tank at low pressure. These valves should be used on larger piston and diaphragm pumps to avoid damage to the pump or other system components when the nozzles are cut off.


Application Equipment, Sprayer Parts -- Pumps

Application Equipment, Sprayer Parts -- Pumps, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

The pump must have enough capacity to supply the needed volume to the nozzles and to the hydraulic agitator (if necessary) and to maintain the desired pressure. The pump parts should resist corrosion, and they should be abrasion-resistant if abrasive materials such as wettable powders will be used. Select gaskets, plunger caps, and impellers that resist the swelling and chemical breakdown caused by many liquid pesticides. Consult your dealer for available options.

Never operate a sprayer pump at speeds or pressures above those recommended by the manufacturer. Pumps will be damaged if operated when dry or with restricted flow at the inlet or outlet. Pumps depend on the spray liquid for lubrication and for cooling the heat caused by friction.


Application Equipment, Sprayer Parts -- Pumps, Centrifugal pumps

Application Equipment, Sprayer Parts -- Pumps, Centrifugal pumps, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Centrifugal pumps are adaptable to a wide variety of spray applications. Generally, they deliver high volume (up to 200 gpm) at low pressures (5 to 70 psi); however, two-stage pumps develop high pressures (up to 200 psi). Pressure regulators and relief valves are not necessary.

Centrifugal pumps are not self-priming and must be mounted below the tank outlet or provided with a built-in priming system. Centrifugal pumps are well adapted for spraying abrasive materials, because the impeller does not contact the pump housing. Many models are easily repairable. The pump case is usually iron; the impeller is iron or bronze.


Application Equipment, Sprayer Parts -- Pumps, Diaphragm pumps

Application Equipment, Sprayer Parts -- Pumps, Diaphragm pumps, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Diaphragm pumps are generally used to deliver low volume (3 to 10 gpm) at low to moderate pressures (10 to 100 psi), but they also can be used for high-volume, high-pressure applications.

Diaphragm pumps withstand abrasion from wettable powder mixtures much better than gear, roller, or piston pumps because the spray mixture does not contact any moving metal parts except the valves. Diaphragm pumps are self-priming. The rubber or neoprene diaphragm may be damaged by some solvents; the pump case is usually iron.


Application Equipment, Sprayer Parts -- Pumps, Gear pumps

Application Equipment, Sprayer Parts -- Pumps, Gear pumps, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Gear pumps are used on sprayers with low operating pressures. They provide low to moderate volume (5 to 65 gpm) at low to moderate pressures (20 to 100 psi). Gear pumps are self-priming, but the self-priming ability is rapidly lost as the pump wears.

Gear pumps are designed for use with formulations that use oil as a diluent. They wear rapidly when wettable powders are used. The parts are generally not replaceable. The pump is not affected by most solvents, because all parts are metal. The pump case may be bronze with stainless steel impellers, or it may be made entirely of bronze.


Application Equipment, Sprayer Parts -- Pumps, Piston pumps

Application Equipment, Sprayer Parts -- Pumps, Piston pumps, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Piston pumps deliver low to medium volumes (2 to 60 gpm) at low to high pressures (20 to 800 psi). Used for high-pressure sprayers or when both low and high pressures are needed, piston pumps are self-priming. They have replaceable piston cups made of leather, neoprene, or nylon fabric, making the pump abrasion-resistant and capable of handling wettable powders for many years. The cylinders are iron, stainless steel, or porcelain-lined. The pump casing is usually iron.


Application Equipment, Sprayer Parts -- Pumps, Roller pumps

Application Equipment, Sprayer Parts -- Pumps, Roller pumps, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Roller pumps are the most widely used of all sprayer pumps. They provide moderate volumes (8 to 30 gpm) at low to moderate pressure (10 to 300 psi). Often used on low-pressure sprayers, roller pumps are self-priming. The pump case is usually cast iron or a nickel-iron alloy.

The rollers, made of nylon, Teflon, or rubber, wear rapidly in wettable powders but are replaceable. A pump subjected to such wear should have a capacity about 50 percent greater than that needed to supply the nozzles and agitator. This reserve capacity will extend the life of the pump.

Roller pumps are usually the best choice for emulsifiable concentrates, soluble powders, and other pesticide formulations that are not abrasive.


Application Equipment, Sprayer Parts -- Strainers (Filters)

Application Equipment, Sprayer Parts -- Strainers (Filters), Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Pesticide mixtures should be filtered to remove dirt, rust flakes, and other foreign materials from the tank mixture. Proper filtering protects the working parts of the sprayer from undue wear and avoids time loss and uneven application caused by clogged nozzle tips.

Filtering should be progressive, with the largest mesh screens in the filler opening and in the suction line between the tank and the pump. Filters should be keyed to the size of the nozzle opening. Total screen area should be large enough so that the flow will not be restricted. This requires at least 2 square inches of screen area for each gpm of flow in the suction line.

Put a smaller mesh strainer in the pressure line between the pump and the pressure regulator, with at least 1 square inch of screen area for each gpm of flow. Put the finest mesh strainer on the nozzle body. Do not use a strainer in the suction line of a centrifugal pump, but be sure the tank has a strainer to take out large particles.

In general, strainers should be placed:

  • on the filler opening (12 to 25 mesh),
  • on the suction or supply line to the pump (15 to 40 mesh).
  • between the pressure relief valve and the boom (25 to
  • 100 mesh).
  • on the nozzle body (50 to 100 mesh).

Clean strainers after each use, or during use if they become clogged. A shutoff valve is needed between the tank and the suction strainer to allow the strainer to be cleaned without draining the tank. Replace damaged or deteriorated strainers.

Strainers are your best defense against nozzle plugging and pump wear. Nozzle screens should be as large as nozzle size permits; however, the screen opening should be less than the nozzle opening. Check nozzle catalogs for the proper screen size for each nozzle.


Application Equipment, Sprayers -- Airblast Sprayers

Application Equipment, Sprayers -- Airblast Sprayers, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Airblast sprayers use a combination of air and liquid to deliver the pesticide to the surface being treated.

These sprayers usually include the same components as low-pressure or high-pressure sprayers, plus a high-speed fan. Nozzles operating under low pressure deliver spray droplets directly into the high-speed airstream. The air blast shatters the drops of pesticide into fine droplets and transports them to the target. The air blast is directed to one or both sides as the sprayer moves forward, or it may be delivered through a movable nozzle.

Most airblast sprayers are trailer-mounted, but tractor-mounted models are available. Tank capacity ranges from 100 to 1,000 gallons. Most of these sprayers can be adapted to apply either high or low volumes of spray material as well as concentrates. Mechanical agitation of the spray mixture is usual. An airblast sprayer may cover a swath up to 90 feet wide and reach trees up to 70 feet tall.

Advantages:

  • good coverage and penetration,
  • mechanical agitation,
  • high capacity,
  • can spray high or low volumes,
  • low pump pressures.

Limitations:

  • drift hazards,
  • use of concentrated pesticides may increase chance of dosage errors,
  • not suitable for windy conditions,
  • hard to confine discharge to limited target area,
  • difficult to use in small areas,
  • high power requirement and fuel use.


Application Equipment, Sprayers -- Backpack (knapsack) sprayer

Application Equipment, Sprayers -- Backpack (knapsack) sprayer, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

One type of backpack sprayer is a compressed air sprayer with a harness that allows it to be carried on the operator's back.

Another type of backpack sprayer has a hand-operated hydraulic pump that forces liquid pesticide through a hose and one or more nozzles. The pump is usually activated by moving a lever. A mechanical agitator plate may be attached to the pump plunger. Some of these sprayers can generate pressures of 100 pounds per square inch (psi) or more.

Capacity of both these types of backpack sprayers is usually 5 gallons or less.


Application Equipment, Sprayers -- Boom sprayers

Application Equipment, Sprayers -- Boom sprayers, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Low-pressure sprayers often are equipped with sprayer booms ranging from 10 to 60 feet in length. The most common booms are between 20 and 35 feet long and contain several nozzles. The height of the sprayer boom must be easily adjustable to meet the needs of the job. Boom supports should allow the boom to be set at any height from 12 to 72 inches above the surface being sprayed. Many nozzle arrangements are possible, and special-purpose booms are available.


Application Equipment, Sprayers -- Boomless sprayers

Application Equipment, Sprayers -- Boomless sprayers, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Low-pressure sprayers that are not equipped with booms generally have a central nozzle cluster that produces a horizontal spray pattern. The resulting swath is similar to the pattern made by a boom sprayer. These sprayers are useful in irregularly shaped areas, because they can move through narrow places and avoid trees and other obstacles. Some low-pressure sprayers are equipped with a hose and handgun nozzle for applications in small or hard-to-reach areas.


Application Equipment, Sprayers -- Bucket or trombone sprayer

Application Equipment, Sprayers -- Bucket or trombone sprayer, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

These sprayers involve a double-action hydraulic pump, which is operated with a push-pull motion. The pesticide is sucked into the cylinder and pushed out through the hose and nozzle with the return stroke. Pressures up to 150 psi can be generated. The separate tank often consists of a bucket with a capacity of 5 gallons or less.


Application Equipment, Sprayers -- Compressed air sprayer

Application Equipment, Sprayers -- Compressed air sprayer, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

This is usually a hand-carried sprayer that operates under pressure created by a self-contained manual pump. The air in the tank is compressed by the pump. The compressed air forces liquid pesticide through the hose and nozzle whenever the control valve is opened. A few types of these sprayers use carbon dioxide cartridges instead of a hand pump for compression. Capacity is usually 1/2 to 3 gallons.


Application Equipment, Sprayers -- Controlled droplet applicators (CDA)

Application Equipment, Sprayers -- Controlled droplet applicators (CDA), Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

These applicators use a spinning disk (or cup) that breaks the liquid into uniformly sized droplets by centrifugal force. The droplets may be carried to the target by gravity or by an airstream created by a fan. Power to spin the disk or cup is provided by a small electric or hydraulic motor. Most CDA's do not use a pump. CDA's range in size from a small hand-held type to large tractor-mounted and trailer-mounted units.

Advantages:

  • requires a low volume of water,
  • produces narrower range of droplet sizes than conventional nozzles, thus reducing drift,
  • droplet size can be adjusted by speed of rotation.

Limitations:

  • gravity type may not penetrate foliage well,
  • not suitable for use in windy conditions.


Application Equipment, Sprayers -- Electrostatic sprayers

Application Equipment, Sprayers -- Electrostatic sprayers, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Electrostatic sprayer systems give the pesticide a positive electric charge as it leaves the nozzles. Plants naturally have a negative charge, so the positively charged pesticide is attracted to the plants. The spray is directed horizontally through or above the crop (depending on the pesticide being applied).

Advantages:

  • pesticide adheres to foliage well, so less pesticide is needed per acre,
  • coverage is more even than with other types of equipment,
  • minimizes the likelihood of drift.

Limitation:

  • useful only for application to foliage.



Application Equipment, Sprayers -- Estate sprayers

Application Equipment, Sprayers -- Estate sprayers, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

These sprayers are mounted on a two-wheel cart with handles for pushing. Trailer hitches are available for towing the units. Spray material is hydraulically agitated. Some models have 15- to 30-gallon tanks. Pumps deliver 1-1/2 to 3 gallons per minute at pressures up to 250 psi.

Larger models have 50-gallon tanks and pumps that deliver 3 to 4 gallons per minute at pressures up to 400 psi. Power is supplied by an air-cooled engine of up to 5 horsepower.


Application Equipment, Sprayers -- Hand

Application Equipment, Sprayers -- Hand, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Hand sprayers are often used to apply small quantities of pesticides. They can be used in structures, and they can be used outside for spot treatments or in hard-to-reach areas. Most operate on compressed air supplied by a hand pump.

Advantages:

  • simple to operate,
  • easy to clean and store.

Limitations:

  • pressure and output rate fluctuate,
  • often provide too little agitation to keep wettable powders in suspension; must be shaken frequently.


Application Equipment, Sprayers -- Hose-end sprayer

Application Equipment, Sprayers -- Hose-end sprayer, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

This device causes a fixed rate of pesticide to mix with the water flowing through the hose to which it is attached. The mixture is expelled through a high-volume nozzle. These sprayers usually hold no more than 1 quart of concentrated pesticide, but because the concentrate mixes with the water, they may deliver 20 gallons or more of finished spray solution per fill.


Application Equipment, Sprayers -- Large Power-Driven Sprayers (Low Pressure)

Application Equipment, Sprayers -- Large Power-Driven Sprayers (Low Pressure), Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

These sprayers are designed to distribute dilute liquid pesticides over large areas. They deliver a low to moderate volume of spray -- usually 10 to 60 gallons per acre -- at working pressures ranging from 10 to 80 psi.

These sprayers usually are mounted on tractors, trucks, or boats, but some are self-propelled. Roller pumps and centrifugal pumps are most often used and provide outputs from 5 to more than 20 gallons per acre. Tank sizes range from less than 50 gallons to 1,000 gallons. The spray material usually is hydraulically agitated, but mechanical agitation may be used.

Advantages:

  • medium to large tanks permit relatively large area to be covered per fill,
  • versatility.

Limitations:

  • low pressure limits pesticide penetration and reach.


Application Equipment, Sprayers -- Large Power-Driven Sprayers (High Pressure)

Application Equipment, Sprayers -- Large Power-Driven Sprayers (High Pressure), Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

These sprayers are used to spray through dense foliage, thick animal hair, to the tops of tall trees, and into other areas where high-pressure sprays are necessary for adequate penetration and reach. Often called "hydraulic" sprayers, they are equipped to deliver large volumes of spray -- usually 20 to 500 gallons per acre -- under pressures ranging from 150 to 400 psi or more.

These sprayers usually are mounted on tractors, trailers, trucks, or boats, or are self-propelled. Piston pumps are used and provide outputs up to 60 gallons or more per minute. Large tanks (500 to 1,000 gallons) are required, because the application rate is usually 100 gallons per acre or more. Mechanical agitators are usually standard equipment, but hydraulic agitators may be used. When fitted with correct pressure unloaders, these sprayers can be used at low pressures. All hoses, valves, nozzles, and other components must be designed for high-pressure applications. High-pressure sprayers may be equipped with a hose and single handgun nozzle for use in spraying trees and animals. These sprayers also may be fitted with a boom for broadcast agricultural applications.

Advantages:

  • provide good penetration and coverage of plant surfaces,
  • usually well-built and long-lasting if properly cared for.

Limitations:

  • large amounts of water, power, and fuel needed,
  • high pressure may produce fine droplets that drift easily.


Application Equipment, Sprayers -- Power backpack sprayer

Application Equipment, Sprayers -- Power backpack sprayer, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

This backpack-type sprayer has a small gasoline-powered engine. The engine drives the pump, which forces the liquid pesticide from the tank through a hose and one or more nozzles. The engine also drives air blowers, which help propel the spray droplets. This model can generate high pressure and is best suited for low-volume applications of dilute or concentrated pesticide.


Application Equipment, Sprayers -- Power wheelbarrow sprayer

Application Equipment, Sprayers -- Power wheelbarrow sprayer, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

This sprayer, like the manually operated wheelbarrow sprayer, has a tank mounted on a wheel for easy transport. It may deliver up to 3 gallons per minute and can develop pressures up to 250 psi. The 1-1/2-to 3- horsepower engine is usually air-cooled. The tank size ranges from 12 to 18 gallons. The spray mixture may be either mechanically or hydraulically agitated.


Application Equipment, Sprayers -- Pressurized can (aerosol sprayer)

Application Equipment, Sprayers -- Pressurized can (aerosol sprayer), Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

This type of sprayer consists of a sealed container of compressed gas and pesticides. The pesticide is driven through an aerosol-producing nozzle when the valve is activated. Pressurized cans usually have a capacity of less than 1 quart and are not reusable. Larger reusable cylinders are available for some specialty agricultural uses.


Application Equipment, Sprayers -- Push-pull hand pump sprayer

Application Equipment, Sprayers -- Push-pull hand pump sprayer, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

This type of sprayer depends on a hand-operated plunger that forces air out of a cylinder, creating a vacuum at the top of a siphon tube. The suction draws pesticide from a small tank and forces it out with the air flow. Capacity is usually 1 quart or less.


Application Equipment, Sprayers -- Small Motorized Sprayers

Application Equipment, Sprayers -- Small Motorized Sprayers, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Some small sprayers have all the components of larger field sprayers but usually are not self-propelled. They may be mounted on wheels so they can be pulled manually; mounted on a small trailer for pulling behind a small tractor; or skid-mounted for carrying on a small truck. They may be low-pressure or high-pressure, according to the pump and other components with which they are equipped.

Standard equipment includes a hose and an adjustable nozzle on a handgun. Some models have multi-nozzle booms. These sprayers are suitable for relatively small outdoor areas.

Advantages:

  • larger capacity than hand sprayers,
  • low- and high-pressure capability,
  • built-in hydraulic agitation,
  • small enough for limited spaces.

Limitations:

  • not suitable for general field use,


Application Equipment, Sprayers -- Trigger pump sprayer

Application Equipment, Sprayers -- Trigger pump sprayer, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

With trigger pump sprayers, the pesticide is not packaged under pressure. Instead, the pesticide and diluent are forced through the nozzle by pressure created when the trigger is squeezed. The capacity of trigger pump sprayers ranges from 1 pint to 1 gallon.


Application Equipment, Sprayers -- Ultra-low-volume (ULV) sprayers

Application Equipment, Sprayers -- Ultra-low-volume (ULV) sprayers, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

These are sprayers that use special pesticide concentrates. ULV sprayers may be hand-held or mounted on either ground equipment or aircraft.

Advantage:

  • no water is needed, so less time and labor are involved.

Limitations:

  • drift hazards,
  • coverage may not be thorough,
  • high concentrates present safety hazards,
  • use of concentrated pesticides may increase chance of dosage errors,
  • few pesticides are labeled for ULV.


Application Equipment, Sprayers -- Wheelbarrow sprayer

Application Equipment, Sprayers -- Wheelbarrow sprayer, Applying Pesticides Correctly -- Private Applicator Supplement, EPA and USDA

Wheelbarrow sprayers are similar to backpack sprayers, but have a larger tank and longer hose line. The tank is mounted on a wheeled cart for easy transport. The capacity of these sprayers is usually less than 25 gallons.


Application, Personal Protective Equipment

Application, Personal Protective Equipment, Applying Pesticides Correctly, EPA and USDA

By law, you must wear the personal protective equipment and other clothing that the pesticide labeling requires for applicators. Consider using additional protection for some types of pesticide application tasks. You may need to weigh several factors before you can make good decisions about the personal protective equipment you should wear.




Application, Personal Protective Equipment -- Adjusting pesticide-coated equipment

Application, Personal Protective Equipment -- Adjusting pesticide-coated equipment, Applying Pesticides Correctly, EPA and USDA

You may need to wear a protective apron while doing some types of equipment adjustments and repairs. Consider wearing a vapor-removing respirator, even outdoors, if you must adjust fumigation equipment.




Application, Personal Protective Equipment -- Applications in enclosed spaces

Application, Personal Protective Equipment -- Applications in enclosed spaces, Applying Pesticides Correctly, EPA and USDA

Pesticides sometimes are applied in enclosed spaces such as warehouses, factories, homes, and other buildings; railcar, ship, and truck cargo areas; silos, elevators, and other grain storage areas; and greenhouses. When you use pesticides in enclosed spaces, you increase the risk of inhaling the pesticide. You may need to use a respirator even if you would not need one for the same application outdoors.




Application, Personal Protective Equipment -- Applying concentrates

Application, Personal Protective Equipment -- Applying concentrates, Applying Pesticides Correctly, EPA and USDA

You may be exposed to highly concentrated pesticides during some applications. Ultra-low-volume concentrates and fumigant formulations may be close to 100-percent active ingredient and often are highly toxic. Consider using extra personal protective equipment when applying concentrates, such as that required for mixing and loading of those formulations.




Application, Personal Protective Equipment -- Applying in air currents

Application, Personal Protective Equipment -- Applying in air currents, Applying Pesticides Correctly, EPA and USDA

If you will be applying pesticides into or across wind or air currents, consider wearing extra personal protective equipment because pesticide may be blown onto you. More body protection, protective eyewear, and a dust/mist filtering respirator may be appropriate.




Application, Personal Protective Equipment -- Entering a treated area

Application, Personal Protective Equipment -- Entering a treated area, Applying Pesticides Correctly, EPA and USDA

Even when you apply a pesticide from a vehicle, you may need to walk into an area that was just treated. For example, you may need to repair or adjust the equipment or check the pesticide dispersal. You probably will be climbing over a contaminated rig and walking through an area that was treated only moments before. Consider putting on additional personal protective equipment while you are out of the vehicle.

If the vegetation in the treated area is covered with pesticide spray or dust and is fairly short, consider shin-high or knee-high boots, or protective footwear with chemical-resistant pants. In this situation, as with walking into the path of the released pesticide, consider applying spray starch or fabric stain protector to pant legs.

If the plants in the treated area are tall, consider wearing a chemical-resistant suit in addition to the footwear. If you cannot wear a chemical-resistant suit because of the heat, try a cape or an apron.

If spray is dripping or dust is falling from overhead, consider a hood or wide-brimmed hat in addition to the body protection and footwear. A dust/mist respirator and protective eyewear may be necessary, too.




Application, Personal Protective Equipment -- Entering

Application, Personal Protective Equipment -- Entering, Applying Pesticides Correctly, EPA and USDA

Many applications performed while on foot cause you to walk into the path of the pesticide you are releasing. Whenever possible, apply pesticides so that you are backing into the untreated area, away from where the pesticide is being released. However, under many conditions, it is unsafe to walk backward in an application site.

If you must walk into the path of the released pesticide, consider wearing shin-high or knee-high boots, or protective footwear with chemical-resistant pants. Spraying a thick coating of fabric starch or fabric stain protectant on the lower legs of your coveralls can provide a temporary barrier for low-toxicity pesticides and also makes the coveralls easier to clean.

When applying pesticides from a vehicle, use equipment that releases the pesticide to the rear so that you are located in front of and above the area of release and are moving away from it. Sometimes, however, you may have to use a vehicle that causes you to drive into the path of the pesticide.

Whether you are walking or riding, if the pesticide is not directed downward or if it remains suspended in the air long enough to cause exposure to the front of your body, wear an apron or chemical-resistant suit. If the pesticide mist or dust reaches as high as your face, consider a dust/mist respirator and eye protection.




Application, Personal Protective Equipment -- Hand-carried application equipment

Application, Personal Protective Equipment -- Hand-carried application equipment, Applying Pesticides Correctly, EPA and USDA

When you carry the application equipment, such as hand-held sprayers or shake cans, you risk being directly exposed to the pesticide. A dripping or partially clogged nozzle, an unfastened cap, a leaky hose, or a loose connection are extremely likely to cause exposure. Consider wearing extra personal protective equipment to protect the area of your body that is in contact with the equipment.

If the application equipment is carried in front, consider wearing a sleeved apron, an apron with built-in gloves and sleeves, or an apron plus arm-covering gloves to protect your front from leaks, drift, and splashes.

If the application equipment is a type that is carried on your back, such as backpack, knapsack, or trombone-style sprayers or dusters, consider wearing a cape to protect your back and shoulders from leaking equipment.

If you carry only the nozzle, consider wearing arm-covering gloves or elbow-length gloves with the cuffs taped or otherwise sealed to the coverall sleeve.




Application, Personal Protective Equipment -- High-exposure applications

Application, Personal Protective Equipment -- High-exposure applications, Applying Pesticides Correctly, EPA and USDA

Certain types of pesticide applications pose a special exposure risk, because they engulf you in pesticide fallout. They include:

  • mist blower or airblast applications,
  • aerosol and fog applications, especially indoors,
  • some applications using high-pressure sprayers and power dusters,
  • applications directed upward over your head, such as to tree canopies or roof eaves, or
  • aerial applications that use human flaggers to mark the swath.

Whenever you work in these situations, large amounts of pesticide fallout are likely to be deposited on your skin and clothing, often to the point of completely drenching or covering you. Unless you are in an enclosed cab, you cannot avoid this exposure, even if you perform the application during times of little or no air currents.

In these situations, you should wear more personal protective equipment than the pesticide labeling requires for other types of applications. Only a chemical-resistant suit with a hood, gloves and footwear with sealed cuffs, and a full-face respirator or half-face respirator with sealed goggles can provide enough protection for these high-exposure applications.




Application, Personal Protective Equipment -- Immersing hands and forearms

Application, Personal Protective Equipment -- Immersing hands and forearms, Applying Pesticides Correctly, EPA and USDA

Some application techniques, such as animal, plant, or seed dipping vats and spray-dip machines, require you to place your hands and forearms into the pesticide liquid or dust. With this exposure, consider a sleeved apron for full front and arm protection, and protective footwear. A face shield will protect against splashes or drifting dusts.




Application, Procedures

Application, Procedures, Applying Pesticides Correctly, EPA and USDA

Every time you apply a pesticide, follow these basic procedures to make sure that you are using the pesticide safely and effectively:




Application, Procedures -- Avoid nontarget organisms

Application, Procedures -- Avoid nontarget organisms, Applying Pesticides Correctly, EPA and USDA

Before you apply a pesticide, clear all unprotected people from the area. It is illegal to allow them to be exposed to a pesticide application -- either directly or through drift. Also remove any pets or livestock not being treated with the pesticide. Even when the pesticide application is narrowly directed such as a crack and crevice treatment, keep people and animals out of the immediate area during application.

Check the pesticide labeling to find out when people and nontarget animals can re-enter the treated area. The labeling of some pesticides may restrict entry into treated areas for periods ranging from several hours to several days. In general, if the pesticide labeling has no such instructions, it may be best to restrict the entry of unauthorized people into the treated areas at least until any dusts or mists have settled or sprays have dried. If necessary, provide ventilation to disperse vapors.




Application, Procedures -- Avoid nontarget surfaces

Application, Procedures -- Avoid nontarget surfaces, Applying Pesticides Correctly, EPA and USDA

When possible, clean the application site of any items that should not be contaminated. Cover or protect any items that cannot be removed from the area and that are not involved in the handling activity, including such things as food and food utensils; bedding; toys; seed; pet or livestock feed, water, or supplies; and other items that could transfer pesticides to people, pets, or livestock.




Application, Procedures -- Check for appearance

Application, Procedures -- Check for appearance, Applying Pesticides Correctly, EPA and USDA

As you apply, notice whether the pesticide you are releasing looks the way it should. Applications of wettable powders usually have a whitish color. If the liquid is clear, check to be sure that you are agitating the mixture enough to keep the wettable powder mixed with the water. Granules and dusts should appear dry and should not form clumps. Emulsifiable concentrates usually look milky. If the pesticide does not look right, be sure you have the right mixture and that it is blended evenly.

Check the appearance of the target area where you have just released the pesticide. If the surface is changing colors or is stained unexpectedly, stop and check whether you are harming the surface.




Application, Procedures -- Check the delivery rate

Application, Procedures -- Check the delivery rate, Applying Pesticides Correctly, EPA and USDA

Check to be sure that you are applying the pesticide evenly and in approximately the right amounts. No puddles of liquid pesticide or mounds of dry pesticide should be deposited in the application area. Be especially careful in areas where you turn or pause. Many types of application equipment continue to release pesticide even when not in motion.

When you have applied the pesticide to the first part of the area or space that is to be treated, check to be sure that approximately the correct proportion of pesticide has been used. If too little is being released, check the equipment openings for clogging or obstructions. If too much is being released, check for worn or stuck openings.




Application, Procedures -- Delivery to the target

Application, Procedures -- Delivery to the target, Applying Pesticides Correctly, EPA and USDA

Take the time to be sure that the pesticide is reaching the surface or space to which you are directing it. Pesticide deposited elsewhere is a waste of time and money and may harm nontarget areas.




Application, Procedures -- Operate equipment safely

Application, Procedures -- Operate equipment safely, Applying Pesticides Correctly, EPA and USDA

Turn off equipment whenever you pause or need to make any adjustments or repairs. When you stop application to take a break, to move to another site, or for repairs, depressurize any pressurized tanks. Turn off the main pressure valve on the tank and release any pressure remaining at the nozzles.

When applying pesticides at a distance from your equipment -- at the end of a long hose, for example -- be sure that unprotected people and pets stay away from the equipment. You may need to post a helper near it.

Check hoses, valves, nozzles, hoppers, and other equipment parts occasionally while you are applying. If you notice a problem, stop immediately and fix it. Do not use bare hands or your mouth to clear nozzles, hoses, or hopper openings. Carry a small nylon brush for such jobs. Be sure that any tool used for this kind of job is never used for any other purpose.




Applied Controls

Applied Controls, Applying Pesticides Correctly, EPA and USDA

Unfortunately, natural controls often do not control pests quickly or completely enough to prevent unacceptable injury or damage. Then other control measures must be used. Those available include:

  • host resistance,
  • biological control,
  • cultural control,
  • mechanical control,
  • sanitation, and
  • chemical control.




Applied Controls, Host resistance

Applied Controls, Host resistance, Applying Pesticides Correctly, EPA and USDA

Some plants, animals, and structures resist pests better than others. Some varieties of plants, wood, and animals are resistant to certain pests. Use of resistant types, when available, helps keep pest populations below harmful levels by making conditions less favorable for the pests.


Host resistance works in three ways:

  • Chemicals in the host repel the pest or prevent the pest from completing its life cycle.
  • The host is more vigorous or tolerant than other varieties and thus less likely to be seriously damaged by pest attacks.
  • The host has physical characteristics that make it more difficult to attack.




Avoiding Harmful Effects

Avoiding Harmful Effects, Applying Pesticides Correctly, EPA and USDA

Pest control involves more than simply identifying a pest and using a control tactic. The treatment site, whether it is outdoors or indoors usually contains other living organisms (such as people, animals, and plants) and nonliving surroundings (such as air, water, structures, objects, and surfaces). All of these could be affected by pest control measures. Unless you consider the possible effects on the entire system within which the pest exists, your pest control effort could cause harm or lead to continued or new pest problems. Rely on your good judgment and, when pesticides are part of the strategy, on the pesticide labeling.

Most treatment sites are disrupted to some degree by pest control strategies. The actions of every type of organism or component sharing the site usually affect the actions and well-being of many others. When the balance is disrupted, certain organisms may be destroyed or reduced in number, and others -- sometimes the pests -- may dominate.