USING EQUIPMENT

IN URBAN PEST MANAGEMENT

Learning Objectives

After completion of the study of Using Equipment in Urban Pest Management, the trainee should be able to:

• Know the benefits and limitations of pesticide application equipment.

• Know simple methods for calibrating urban pesticide application equipment.

• Understand how safety is part of every phase of equipment use.

The most needed and reliable tool of all in pest management is the brain and ability of a technician to use his knowledge of pest management along with well‑cared‑for equipment and good supplies. Pesticide application equipment used in urban pest management is, for the most part, time tested and reliable. It is reassuring and convenient to have tools that seldom fail. Time, training, and the encouragement of regular cleaning, calibration, and repair of tools means a planned program and good supervision.

Failure to care for equipment properly can cause serious problems. Using worn or clogged spray nozzles or caked dusters results in misapplied pesticides. Accidents from breaking hoses and exposure from leaking valves can result in lost time, illness, and complaint or lack of confidence from clients. Lack of attention to these activities is a sign of mismanagement of time, over scheduling, miscommunications and unclear priorities.

The more commonly used equipment includes: 

Spray Patterns

The most common nozzle for the hand-held compressed air sprayer is made of brass and usually can be set in one of four spray patterns. More than four patterns are available, however. The most common patterns include two pin streams, flat fans, and cones.

Pin streams can be coarse or fine. The coarse or fine pin streams do not produce the best crack and crevice application. Even when set for fine spray, a stream is produced that splashes back from all but the widest crack, so many nozzles have a connection for a narrow-diameter plastic extension tube. Remember  to use equipment as directed (e.g., injection tool for crack and crevice application). The end of the extension tube is inserted into or at the edge of a crack and delivers an accurate pin stream: overall the most effective spray pattern for cockroach pesticides application. .

Coarse and fine flat fan streams are used to apply general or spot applications, as are hollow or solid cone sprays. Cone sprays deliver a circle of pesticide and are often used outside on uneven surfaces and plants.

Pressure
Spray tank air pressure varies according to the amount of air the technician pumps into the tank. Pressure gauges can be attached to spray tanks. Low pressure is usually recommended for spray application inside structures. Constant use of high pressure with compressed air sprayers sets up the possibility of overuse and misapplication. It causes part of the sprayed liquid to break into droplets as soon as it exits the nozzle; this wastes material that can drift onto non-target surfaces. High pressure also causes splash back on surfaces or quickly traps air in crevices and keeps the pesticide from entering small spaces. As well as being uneconomical and wasteful, the practice encourages rapid application of pesticides whether they are needed or not, from distances that affect accuracy. This style of pesticide application will seldom result in effective pest control, especially where German cockroaches are a problem.

POWER SPRAYERS
As their name implies, power sprayers use electric or gasoline engines to pump liquid insecticides from a relatively large tank, usually over 100 gallons. The liquid is discharged thru a 3/8 or 1/2 inch hose of sufficient length to reach from the pump to the application site.
 Power sprayers are generally used for one of two types of urban pest control:
(1) controlling termites, and
(2) spraying building perimeters and lawns. In the southern United States, power spraying outside in conjunction with inside treatment for cockroaches is common. In warmer climates, large cockroaches (American, oriental, smoky-brown, etc.) are active outdoors as well as indoors. Other types of outside pests (e.g. ticks, crickets, millipedes and other miscellaneous invaders) are also treated by spraying outside. Here too, low pressure is more effective than high pressure because the pesticide will not blast away the surface dust or soil and runoff. Low pressure allows for a more careful application, better soaking action, and better penetration through short grass. Special attention should be paid to the hose of power sprayers: both in the quality and points of wear. Wear or cuts cause hoses to burst; when this happens pesticides spill and cause contamination. Shutoff valves should always be in good working order.
Equipment to take care of spill contamination should always be carried in the service truck.

  Why calibrate spraying equipment?
In urban pest management, much is up to the judgment of technicians. A pest control technician should know that the proper dosage of pesticide is being applied; accurate calibration of power sprayers is important or the amount of pesticide delivered will be incorrect. Over-dosage will contaminate the spray area or result in runoff. Less than recommended dosage e may fail to control the pest. Technicians need to regularly look at the output of their equipment. Flow meters are very helpful to let the technician know the output of the sprayer over time.

It is estimated that 60 percent of sprayers have a calibration error up to 10 percent. A large percentage of sprayers have greater than 10 percent variation in discharge from individual nozzles or tips. Application methods used by different applicators vary, depending upon pressure, nozzle tip, etc. Soil types and types of soil cover (grass, mulch, gravel) can influence the rate of pesticides a technician applies.

Manufacturers' instructions, university extension training meetings, label instructions and company policy should be considered and used to calibrate sprayers. Refer to company policy and core manual for calibration instructions.

CANNED INSECTICIDES Pressurized cans of insecticides became common in the late 1940s and were first used as aerosol foggers or "insect bombs." Canned insecticides in urban pest management include canned aerosol foggers (volumetric sprays, total release fogs) and pressurized liquid sprays. (The garden type aerosol or the over the counter aerosol generally sold to the public for contact spraying is NOT included in either of these categories.) in the air for a period of time, then settles to the ground. The droplet size is governed by the nozzle and valve at the top of the can. After use, a more or less uniform coverage will be attained on exposed horizontal surfaces. Very little pesticide lands on vertical surfaces, penetrates opened cabinets, or clings to under surfaces. Droplets contact pests that have left hiding places, and other insects that fly into the insecticide are killed.

Canned Pressurized Liquid Sprays Canned pressurized liquid sprays are not aerosols. Because the coarse, wet spray is not made up of aerosol droplets, little becomes airborne. Compressed                                                     gas mixes with the pesticidal liquid in a pressurized spray. The gas forces the pesticide through the exit port, quickly vaporizes, and leaves pesticide on surfaces. When canned p                               ressurized liquids are part of a system that includes crack and crevice nozzles, the insecticide can be placed precisely on the target area. In a closed crevice, the expanding gas propels th                            e insecticide in all directions forcing it on all surfaces in the crevice, rather than shooting it across in a straight line like a compressed air sprayer. Using canned pressurized liquid sp                   rays requires a firm understanding of the target pests' habits so that pest harborage can be treated.

AEROSOL AND FOG GENERATORS Power aerosol and fog generators break liquid pesticides into aerosol droplets. Reducing the liquid into droplets is done either mechanically (cold foggers) or by using heat (thermal foggers). Caution should always be taken to protect the applicator's respiratory system when these generators are used. 
Cold Foggers 
Cold foggers break an insecticide into aerosolized droplets and propel them into the air in a light cloud or fog. Large, ultra low dosage (ULD) and ultra low volume (ULV) cold foggers are mounted on trucks and used in mosquito control programs, to control pests in large warehouses, and for fly control in some operations. Cold fog generators drive pesticidal fog over a relatively large area. Droplets fall on flying or resting mosquitoes or are deposited in very small amounts on plant leaves on which mosquitoes rest.
     Hand-held cold foggers are used inside buildings where they fill rooms, small warehouses, etc., with aerosol droplets. These floating droplets kill flying insects as well as exposed insects on horizontal surfaces. Fogs do not enter tight spaces or cracks and crevices. While some aerosol generators are used for crack and crevice applications, they also produce aerosol droplets that float in the air. 

Thermal Foggers 
Thermal foggers use heat to vaporize oil in an oil-based insecticide formulation. Large truck-mounted thermal aerosol generators are used in mosquito control programs where the insecticide fog rolls across open spaces killing flying insects as air currents move it. Indoors, portable thermal foggers work like cold foggers except droplets are smaller. 



Precautions. 
When using fogging or aerosol generating equipment indoors: 

For General Application 
Fogging should not be used as a single method of treatment but as a supplementary method to other types of application. Fogging or aerosol application is a general pesticide application and only pyrethrins or insecticides labeled for unclassified application can be used in this way. If fogging treatments begin to be used at increasingly closer intervals, it means that the pest population is not being suppressed and may be increasing.

DUSTERS 
Dusters apply a fine, dry layer of a powdery mixture containing a small amount of pesticide. Dust applied on porous surfaces is not absorbed like liquids; it rests on them like a layer of insecticidal powder. This dust accumulates on body parts (insect hairs, legs and mouthparts) of insects who touch it. Pesticides in dusts are absorbed by the insecticide in the same way as liquid sprays. Additionally, if the pest ingests particles (when grooming or cleaning itself), the dust can also cause stomach poisoning.

Hand Dusters
Three types of hand dusters are commonly used by pest management technicians: bulb, bellows, and plunger dusters. Dusts are also driven by gas in some formulations of canned insecticides, but with this method, dusts are applied like canned liquid pesticides. Bellows dusters consist of a closed rubber cylinder made rigid by an internal spring, a spout at one end, and a stoppered refill hole at the other. These dusters, originally called Getz dusters, are held with the spout at the top. A slight pressure from top and bottom pushes air and dust from the spout. The more pressure applied, the more dust ejected. The spout is tapered at the tip and slight puffs will propel small amounts of dust into cracks and crevices. The slight puffs distribute a thin layer of dust in the pest harborage. Bulb dusters have a rubber bulb with a removable spout at one end. The spout screws off to allow for refilling. Dust application is much like the bellows duster except that the bulb is squeezed. Both dusters come in several sizes. Plunger dusters hold more dust than the first two hand-held dusters discussed. Plunger-type dusters have been used for garden dusting for a century, but the plunger duster used in urban pest management is smaller, made of high impact plastic
 and has several styles of nozzles.

Power Dusters
Most power dusters use compressed air to deliver insecticidal dusts to large spaces. Fire extinguishers have been converted to dusters and filled with compressed air. Other dusters are plastic and are pumped up much like the hand-held compressed air sprayer used to applying liquids. The plastic dusters release small or large amounts of dust with better control than the fire extinguisher type. Power dusters are often used in spaces where the dust can lie undisturbed providing a residual coating of pesticide. They are also applied in sewers as contact pesticides and in trash chutes of high rise buildings. The dust is introduced at the lowest level at a trash compactor and rises up through the chute where it is vented at the top. The chute must be closed at each floor. Dusts can also be placed in wall voids, crawl spaces and almost any unused space. Sometimes drilling into voids is necessary to inject dust. Great care must be taken to confine dust so that it does not drift and is not carried into non-target spaces. Remember to turn off pilot lights and flame or spark producing equipment if a combustible dust is used. Protect smoke alarms when using dust. Dusters clog easily. They must be agitated often and the dust kept dry at all times. Dusters work much better if they are often washed and dried.

TRAPS Traps, Bait Boxes, Monitoring Devices, and Pheromone Dispensers
Traps have been used for pest control for centuries. Rodent control traps range from snap traps to boxes that use trap doors, spring loaded multiple catch traps; and small animal traps. Rodent bait boxes, or bait stations, are containers that hold poisonous baits or glue boards. Under certain conditions, they must be tamper proof for safety. Other traps to catch pest birds are baited so the bird will enter and cannot get out. Fly traps are sticky tapes or cylinders that hang vertically, taking advantage of the fly's tendency to cling to vertical poles, strings, etc. Electric fly traps are made with an attracting light that lures flies to electrocution grids or glue boards. Sticky traps are small glue boards used to catch cockroaches. These are used to monitor roach populations and to survey for other insects. Pheromone traps lure insects with a pheromone (a natural attractant), to a sticky holding surface. These traps are used to evaluate insect populations; their catches indicate which species are present. They may also be used to control or reduce pest populations. Bait Stations There are many kinds of bait stations. These devices confine toxic substances to units that are removable rather than leaving them exposed. Cockroach bait stations offer pesticides as attractive bait. The bait stations themselves offer natural harborage. They can augment sprays, dusts and fogs, or they can be used in place of other more toxic formulations. The key to using these devices is to know where and how to place them.

SUMMARY
Equipment is used in urban pest management and control to suppress pest populations; it is effective only when used by competent pesticide applicators. Pest control equipment used by an untrained applicator who has little practical knowledge will be used ineffectively. Ill-cared-for equipment in bad repair is ineffective and dangerous. To use pesticides efficiently and economically (without under application [lack of control] or over application [unsafe]), applicators must understand the capabilities of their equipment and be able to depend on correct calibration. They must also be aware of the many types of equipment available. Urban pest control equipment is not only sprayers and dusters, but includes other devices such as traps, bait stations, lights, excluders, etc.

STUDY QUESTIONS FOR MANAGEMENT & CONTROL CHAPTER TWO USING EQUIPMENT IN URBAN PEST MANAGEMENT