4. Research the heating system and the use of natural gas in the building (for all spray and dust treatments). Depending on the pesticide and the application method, the blower on forced air furnaces may need to be shut off. As well, when using oil based aerosols, the pilot light on the furnace and on all other natural gas appliances must be shut off. 5. Keep all people and pets away from the treatment area during any application. 6. Decide on safe re-entry times. The re-entry time is the amount of time that people (i.e., residents or workers) must stay out of treated structures. The concern over re-entry times is one of pesticide exposure to those living, or working, in pesticide treated environments. Exposure can be through inhalation of volatilizing pesticides or by touching pesticide residues on treated surfaces. Volatilization is the term used to describe the release of pesticide vapours into the air.
Mixing and Applying PesticidesOne area of confusion is whether or not two or more pesticides can be mixed together. If the pesticide label does not state clearly that two pesticides can be mixed, then it is illegal to mix them. Pesticides must be used according to the label instructions. For example, although chlorpyrifos and methoprene can be purchased for flea control as a premixed product, the pest manager cannot buy the separate products and mix them in the tank because the labels do not say that they can be mixed. A product label in the U.S.A. may allow mixing, while a Canadian label may not. This may be because the manufacturer has not applied to have mixing added to the Canadian label, but it is still necessary to follow the directions on the Canadian label. 1. Read the pesticide label every time. Don't rely on your memory. The use instructions may have changed since the last time you purchased the pesticide. 2. Read the material safety data sheet. Material Safety Data Sheets for most pesticides are available from pesticide distributors. 3. Put on your personal protective equipment. Refer to the "Handbook for Pesticide Applicators and Dispensers - Chapter 6, Protective Gear and Clothing". 4. Follow all label directions. Before opening the container, pay strict attention to the warning and caution symbols on the label. 5. Mix pesticides outdoors. If this is not possible, mix indoors in a well ventilated area. 6. Use a clean measuring container for water. Do not put hoses into sprayers or sprayers into sinks to fill them with water. 7. Rinse empty liquid concentrate containers three times. When making a water-based spray mix, add this rinse water to the spray tank. 8. Work cautiously to avoid spills. If a spill occurs, take immediate action to protect yourself, your client and the client's property. 9. Apply the mixed pesticide only to appropriate areas. For example, some pesticides are only for cracks and crevice or for spot treatment. 10. During application, watch the equipment for malfunction or leaks. If there are leaks or the spray pattern is not as expected, then! Clean the sprayer, fix the equipment or replace nozzles. Correct the problem before continuing. 11. Wipe up excess pesticide (e.g., over spray that is unwanted). Always have clean rags. 12. Whenever possible, do not apply pesticides on food preparation surfaces. If you must spray around food preparation surfaces, leave a note asking the kitchen staff or home owners to clean the surface before using it. Leave written instructions on how to clean (e.g., use soap and water for specified surfaces). 13. Be thorough. Ensure that everything that must be treated is treated. Second treatments are costly and can result in excess pesticides being deposited in treated areas.
After Treatment1. Clean application equipment. Avoid contaminating surfaces where bystanders may linger or walk. 2. Dispose of empty pesticide containers. Do not leave empty containers at the treatment site. When properly rinsed, they can be disposed of in municipal landfills. 3. Keep records of pesticide treatments, incidents and accidents. Later analysis of your records may help you to improve your handling of pesticides. 4. Ensure that treated areas will be aerated as required. Home owners should be told to open windows and to air treated rooms. In commercial buildings, the building manager can be asked to resume ventilation and to increase makeup air to the building and/or to increase total ventilation. 5. Remind clients to stay out of treated areas until the specified re-entry time. The re-entry time should also be posted on the door.
Additional Precautions for Specific Application MethodsBroadcast SpraysBroadcast sprays are the application of liquid sprays to cover a large portion of the floor area in a room with a uniform application rate. See "General Precautions for Most Pesticide Applications" as well as the following. 1. Ensure that residents have been notified that a pesticide is being applied. A few questions will tell whether residents are aware of the precautions they must take. 2. Inform residents of the safe re-entry time. Current industry recommendations require that people stay out of treated structures for 6 to 24 hours (see note below). 3. Remind clients not to allow infants or children to run bare foot or roll around on rugs or other sprayed surfaces. The 'Resident's Notice' should contain written instructions. 4. If shelf edges have been sprayed, remind clients to line all shelves with paper or plastic. The 'Resident's Notice' should contain written instructions. 5. Walk through the house/building to ensure that children's toys, and clutter (such as papers or refuse) have been removed. The 'Resident's Notice' should contain written instructions. 6. Ensure that foodstuffs are put away or covered with a sheet. No Exceptions. 7. Ensure that all pets and aquariums have been removed from the areas being sprayed. If aquariums cannot be removed, cover them with a cloth and turn the air pumps off before spraying. Leave the pumps off for 6 hours after spraying. 8. If required, close windows to prevent spray drift. (e.g., where draughts could displace spray patterns; windows should be opened following treatment). 9. Ensure that extractor fans are shut off as required. Prevent pesticide vapour movement to untreated rooms. Ensure treated rooms are ventilated before re-entry.
Microencapsulated pesticides can be safer to handle than other formulations because the capsules cannot be absorbed through the skin and will pass through the digestive tract if ingested. The capsule extends the residual life of the pesticide by slowing the rate at which the pesticide volatilizes. This results in lower concentrations of insecticide in the air and can mean reduced exposure for clients when compared pesticides that are not microencapsulated.
Spot SpraysThe term "spot spray" refers to the practice of applying insecticide to a small areas. An example is applying a treatment for fleas just to the sites where dogs or cats rest. See "General Precautions for Most Pesticide Applications" as well as the following: Evacuation of the premises may not be necessary if the spot treatment is small. Otherwise, use the same re-entry times given for broadcast sprays. Ensure that all pets and children are kept away during treatment and prevented from contacting sprayed surfaces areas until they are thoroughly dry.
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Describe the general guidelines for communicating with home owners, managers and tenants.Typical re-entry times for crack and crevice treatments with residual pesticides are:
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Perimeter or Band Sprays
Perimeter or band sprays are often used to limit the movement of insects such as ants. This application method involves spraying a narrow band around the inside or outside of a house foundation. The insecticide residue repels insects from entering or from moving easily around the room or building.
Bands should be placed where insect pests are traveling. For example, when ants search for food they usually move along specific trails. If a band of insecticide is placed across the ant trail, entrance into a structure is often interrupted. The advantage of a perimeter spray is that the volume of pesticide used within a building is considerably reduced over the amount used in a broadcast application. The disadvantage is that generally, perimeter sprays only suppress the activity of insects. They may only provide short-term control unless coupled with additional actions such as removing water damaged wood or eliminating ant nests.
To obtain a narrow spray pattern use the correct nozzle and nozzle pressure. Using a low pressure reduces spray drift. When odourless, wettable powders like bendiocarb (without pyrethrins) are applied as band sprays, workers or residents can resume occupancy more quickly than for broadcast sprays.
See "General Precautions for Most Pesticide Applications" as well as the following:
1. Inform residents of safe re-entry time.
Current industry recommendations require that people stay out of treated rooms for 4 to 8 hours (see box following):
Typical re-entry times for areas treated with perimeter or band sprays with residual pesticides are:
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Ultra Low Volume Space Sprays
Ultra low volume (ULV) sprays use a gas (often air) as the insecticide carrier instead of using water or oil. This means that very low volumes of the pesticide product are applied (although the amounts of active ingredient used could be similar to that used in sprays with liquid carriers). ULV space sprays contaminate all surfaces in the treated areas.
Pyrethrins and allethrin space sprays are sometimes used within buildings to control flying insects. They may be applied using non-refillable aerosol containers or specialized aerosol generating applicators. This method of pest control is used primarily to combat sudden appearances of flying insects in areas with low insect tolerances. ULV space sprays would rarely be needed in an IPM program that employs regular inspections, preventative maintenance, light traps and pheromone traps for flying insect control.
Crack and crevice ULV sprays are now more commonly used than space sprays. Aerosol cans with straw tips or special ULV crack and crevice machines are used to apply small amounts of pesticide into cracks and crevices where insects hide. The ULV sprays penetrate well into recesses.
The main safety hazard for the pest manager is from inhalation during ULV applications. The ULV applicator generates very small insecticide particles, which can be inhaled deeply into the lungs and are slow to settle out of the air.
See "General Precautions for Most Pesticide Applications" as well as the following:
1. If motorized ULV equipment is being used in a very dusty environment (e.g., a flour mill), have an explosion proof motor on the equipment.
Gas engines cannot be used in dusty environments.
2. Make a walking tour. Ensure that all pets and aquariums have been removed.
If aquariums cannot be removed, they must be completely covered and the pumps must be disconnected during treatment and for 6 hours after treatment.
3. Ensure that plants have been removed or are covered.
Oil-based insecticides can cause plant damage.
4. Ensure that extractor fans are off and that air is not being extracted out of the room in some other way.
Use a lighted tissue paper or smoke tube to test for air movement. Remember that drop ceilings can act as a plenum for general ventilation.
5. Ensure that windows are closed and that doors to the treatment area are also closed.
This ensures that the spray stays in the treatment area for the duration of the treatment.
6. In kitchens, ensure that cabinet doors and drawers are wide open.
The contents must be removed, placed away from the spray operations, and covered.
7. Turn off pilot lights and do not flip light switches on or off during spraying.
These can be a heat source for explosions.
8. Wear a respirator and eye protection.
A cartridge respirator may be adequate if you release the pesticide as you exit and so do not enter the spray cloud. A canister respirator is required if you must enter the spray cloud.
DANGER: Respirators will not seal properly over a full beard. Never try to seal a respirator by placing vaseline on the edges of the face mask where the rubber meets the face. Grease and oils increase the amount of pesticide that is absorbed by the skin. |
9. Read the pesticide label and follow directions as to the application rate.
The directions specify that an oil-based aerosol is to be applied at a certain quantity per volume. Exceeding the application rate could cause an explosion if the concentration reaches the combustible rate for kerosene in air (1 gallon in 50,000 cubic feet).
DANGER: There is a history of explosions when the concentration of oil-based aerosols reaches the lower limit of kerosene combustibility. |
10.Two hours after application, or according to the label, ensure that extractor fans are turned back on and/or windows and doors are opened for ventilation
Increase the rate of mechanical ventilation if possible. Treated areas must be ventilated before re-entry.
The typical re-entry time for ULV treatment using pyrethrins is a minimum of 6 hours for all residents. |
Dusting
Insecticidal dusts are used to control cockroaches, silverfish, carpenter ants and other insects that hide in cracks and crevices and in wall voids. To be effective, the dust must remain dry and it must be applied very thinly so that it won't repel insects.
There are hand dusters, ULV dusters and large volume power dusters. Typically, hand dusters and ULV dusters are used for crack and crevice dusting. Large-volume power dusters have little use in IPM programs as they emit large volumes of dust in a short time.
See "General Precautions for Most Pesticide Applications" as well as the following:
Hand Dusting
1. When dusts are applied to cracks and crevices, use light pressure on the duster.
Low pressure minimizes dust blowback. Also, a fine dust on surfaces is all that is required. Excess dust repels insects.
2. Place ball bearings inside the duster and shake the duster frequently while dusting.
This breaks up clumps and ensures even output.
3. Keep the spout above the level of the dust inside the duster.
This prevents excessive output.
4. Fill the duster no more than two thirds full.
This allows room in the duster for the air and dust to mix.
5. Place a plastic or rubber cover over the tip of the duster before dusting around electrical outlets or electrical equipment.
This prevents electrical shock, should you happen to touch a bare wire or other electrical source.
6. When finished dusting, store hand dusters in tight dry containers or in Ziploc™ bags.
Ensure that the duster does not get wet and does not contaminate anything else.
7. Clean dust off all exposed surfaces or brush the dust into the cracks.
This limits exposure of people and pets to pesticides.
Power Dusting
1. Protect children's toys, clothing and furniture that could be exposed to dust.
Remove them to rooms that will not be treated or seal them in plastic.
2. Ensure that foodstuffs are put away or covered with a sheet.
3. Ensure that all pets have been removed from areas being dusted.
4. Ensure that extractor fans are shut off as required during treatment.
Toxic Baits
Toxic baits are used to control many insects and rodents. In structural pest control they are used for mice, rats, cockroaches and ants. A successful bait must attract the pest and encourage feeding. The bait usually must not repel the pest after one feeding unless a single dose is effective. It is important to choose baits appropriate to the lifecycle and behaviour patterns of the pest. For example, ant baits are formulated to attract the ants and to act slowly enough for the ants to pass the poison on to other members of the colony.
The formulation of baits and the location and types of containers for application depend on the target pest. Often, attractants are added to baits to increase the likelihood that target pests will consume them.
Toxic baits localize the pesticide and reduce the amounts that are used and also wasted.
Insect baits are available in granular, paste, gel or tablet form. Some of the most effective baits are in a paste form. For example, Blue Diamond MRF® is a commercial boric acid bait paste formulated with food attractants for cockroach control.
Insect baits can be used safely in areas where there is public access. Care must be taken in food preparation areas to prevent the possibility of a bait falling into food. Follow all label recommendations regarding the placement of insect bait.
Rodent baits are available as loose meal, pellets, or blocks. These may be oiled,waxed, or packaged in plastic pouches (throw packs). Rodent baits are highly toxic and must be placed in a way that will prevent exposure to people, pest and other non target animals. This usually means inside sturdy, locking, tamper-proof bait stations. Bait blocks should be secured inside the station to prevent rodents from dragging the bait to non-target areas. Bait stations should be wired down, glued in place or otherwise secured to prevent them from being dragged away and to keep loose baits from spilling out. This is especially important for pellet and meal baits to prevent the bait from being tipped out the bait box.
1. Do not sell any rodent control products to household clients for their own use, other than those products with a Domestic label.
You must have a Vendor licence and Dispenser certificate to sell even Domestic pesticides.
2. Keep the telephone number of the local poison control centre and/or rodenticide manufacturer's hot-line in your service vehicle.
This is for quick reference in an emergency.
3. Keep copies of rodenticide labels in your service vehicle.
In an emergency, a physician or veterinarian may need a copy.
4. Stay current with WHMIS and other regulations that affect your clients (e.g., Health Protection Branch regulations).
This is especially important for commercial businesses involved in food processing.
5. For commercial or industrial situations, give copies of the label and Material Safety Data Sheet (MSDS) to the client.
6. Place rodenticides in tamper-proof bait stations.
7. Label each bait station clearly with "Rodent Bait - Do Not Touch". Write your name and phone number on the container.
8. Show the client a bait station and explain how it is tamper proof. Note that your name and phone number are on the label.
9. Ask the client if children or pets are likely to get into the area where you are planning to place rodenticide baits.
If the answer is yes, find out which areas are inaccessible to children and pets. Err on the side of caution, however, because the information you receive can be incomplete or inaccurate.
10. Place baits in areas that are inaccessible to children and pets.
If all areas are accessible to children and/or pets, use non chemical control measures.
11. Wherever possible, avoid placing rodenticide baits in public areas.
It is best to keep even tamper-proof bait stations out of sight so that someone is not tempted to pry them open.
12. If a rodent population is in a ceiling, use traps before baits.
Poisoned rodents may die in inaccessible locations and produce odours as they decompose.
13. Do not use baits in a dropped ceiling where the bait may fall into a food preparation area.
If you absolutely need baits, use blocks of paraffinized bait fixed in a tamper proof bait container.
14. Place baits so that food and food contacting surfaces are not contaminated.
Never place bait stations where they could be easily knocked over and spill bait to contaminate sensitive areas.
15. Use meal baits or secured bait blocks inside bait stations in preference to pellets, throw packs or unsecured bait blocks.
Rodents may move pellets, throw packs and bait blocks into high-risk areas.
16. Keep detailed records of where rodenticides are placed on a client's property.
You will need to know if any bait stations are moved or are missing. You should always collect all baits after the treatment.
17. Inform the client in writing about the rodenticide being used and about the location of bait stations.
See "The Notice to Residents" - this chapter.
18. If an infestation has been eliminated, ensure all baits are removed from the treated property.
The uneaten bait should be removed and reused or properly disposed of if it is no longer required.
19. Following control operations, dead rodents, especially rats, should be recovered and removed (wherever possible).
They can be picked up safely using plastic gloves. It is acceptable to dispose of dead mice or rats in household garbage if there are only a couple of carcasses. Large numbers should be incinerated or, in rural areas, buried deep enough in the ground so they will not be dug up by pets or other carnivores.
Communications
In the planning stages, the pest manager should talk with the client and find out:
- what the client expects from the pesticide application, and
- whether any individuals are particularly at risk because of pregnancy, allergies, heart or respiratory problems.
The pest manager must advise the client about their role in the pest control operations. Clients need to know what is expected of them before, during and after pest control operations. They also need to know what to expect in the way of results from the treatment program.
Residents of multi-dwelling units and workers in commercial buildings must be notified and told about the pest control program. This is the joint responsibility of the pest control company and the building management. Educational materials can be announcements on bulletin boards, flyers, posters, small stickers, cards, or leaflets placed inside a company's newsletter. Sometimes, it may be appropriate for the pest manager to take part in a staff meeting or to give a presentation about the program and the level of cooperation that is needed for success. This is particularly important in IPM programs, where residents may be asked to contribute to sanitation and prevention efforts.
Educational materials or programs should cover the following points:
- the pest management program will focus on preventing pest problems and minimizing pesticide use,
- the residents or office workers have an important role in assisting the pest management program by:
- cleaning their offices, kitchens or units of all food scraps, crumbs, soft drink cans, etc.,
- removing food or placing stored food in tight containers or the refrigerator,
- carrying out other specific actions, which should be listed.
Consider including drawings when giving written instructions. Drawings help those who cannot read and those for whom English is a second language. Make sure that instructions are presented to residents or tenants by an informed pest manager or building manager. That person should be knowledgeable enough to explain the process and to answer questions.
Where a sequence of treatments will be carried out, communication is often improved by keeping a log book in a central location. Employees or tenants may use the book to communicate with their management and with the pest manager. All complaints should be handled by one person only. That person might be the pest manager who regularly services the building or a management person from the pest control company. Where there are areas of concern, pest control operations can be modified.
In apartment clean-out operations, the management should distribute a "Notice to Residents" some time before the control operations are to begin (at least 72 hours). Those tenants with relevant medical problems should be allowed to opt out of a spray program. Forcing tenants to have their apartment sprayed should be avoided in favour of an offer to use alternative control measures. Enforcing compliance with the alternative control measures is the responsibility of the apartment manager and not the pest manager.
All pest control agreements should state what the pest manager is responsible for and what the manager is responsible for.
The Notice to Residents
The Integrated Pest Management Act Regulation specifies when treatment notice is required and what information it must convey. For information of Treatment Notices, see the Handbook for Pesticide Applicators and Dispensers.
A “Notice to Residents” is additional information given to residents of a building that is to be treated.
For all treatments, the Notice to Residents should include:
- the treatment date, starting time of application and planned completion time,
- re-entry information stating how long the client must stay out of the treated structures,
- a note describing how you are complying with the requirements of local pesticide notification bylaws or guidelines, and
- a request that any signs of continued infestation be reported to the pest manager.
In addition, for most spray and dust applications add notification about the following as required:
- cover foods or place them in an enclosure (e.g., a refrigerator),
- remove pets and aquariums from the building (where aquariums cannot be removed, they should be covered with a cloth and the air pumps turned off during spraying and for 6 hours after spraying),
- cover dishes and food preparation surfaces, or before use, wash with soap and water any food preparation surfaces that could not be covered,
- aerate the sprayed area thoroughly before re-entry,
- look for a sign on the door stating what has been done and when they can re-enter,
- for crack and crevice sprays in cupboards and dressers, advise residents to clear shelves and empty drawers; place contents away from spray operations and cover them; then replace drawers for treatment. After treatment, advise them not to wash sprayed areas. Instead they should lay a paper liner before replacing the contents. Liners may be removed one month after the application if the client wishes.
- for ULV space sprays, turn off pilot lights on gas appliances (e.g., gas stoves, furnaces, etc.)
- inform the applicator if any resident suffers from asthma, other allergies or relevant medical conditions,
- remove or seal in plastic any toys, clothes or furniture that could be exposed to the insecticide.
For rodenticide baits add notification about the following as required:
- the name and mode of action of the rodenticide,
- that rodenticide baits must not be moved,
- a diagram of the location of bait stations, what they look like and how they are secured in place (note particularly if baits have been placed in areas other than at floor level),
- the date and time of the next visit,
- instructions on disposing of rodent carcasses,
- precautions that the owner can take to ensure that children and pets cannot get to the poison baits (such as locking doors to areas where baits have been placed, refraining from moving appliances such as stoves or refrigerators when baits are located behind them),
- whether or not the baits will be removed when the rodent population has been eliminated (if a permanent baiting program is undertaken, note how often the baits are changed).
In conclusion, the IPM decision making process may determine that pesticides are a necessary management tool for a particular pest problem. The IPM approach then would include:
- selecting the least toxic pesticide that will do the job,
- using an application method that minimizes pesticide distribution, and
- using all possible precautions to prevent exposure of humans and non target organisms to pesticides.'
Further Reading
Adams, R. W. 1995. Handbook for Pesticide Applicators and Dispensers,. 5th ed. BC Environment, Victoria, B.C. 253 pp.
Marer, P. J. 1995. Residential, Industrial, and Institutional Pest Control. University of California Statewide IPM Project. Pub. 3334. Oakland, CA. 213 pp.
| Study Questions - Chapter 12 Answers are given here. |
| 1. What are the requirements for using toxic pesticides in an IPM program? |
| 2. Why is the use of toxic baits preferred over a crack and crevice spray? |
| 3. Why is it important to research the ventilation system in a building before treating with a pesticide spray? |
| 4. Define the term 're-entry time'. |
| 5. What do most labels indicate is the re-entry time for pesticide sprays? |
| 6. List five general precautions that should be followed after most pesticide treatments. |
| 7. For crack and crevice treatments what steps should be taken to prevent contamination of items in drawers and on shelves? |
| 8. List four precautions to prevent children being exposed to rodent baits. |
| 9. When residents or office workers must be asked to contribute to sanitation and prevention efforts, what information should be communicated to them and how should this be done? |
| 10. Describe the use of the "Notice to Residents". |
| 11. Answer True or False for the following: |
| ___ Two pesticide products can be mixed together, provided the labels do not prohibit mixing. |
| ___ Notification is a legal requirement in some cities such as Burnaby and Vancouver. |
| ___ For all application methods it is necessary to shut off the pilot light on natural gas furnaces. |
| ___ If a spray pattern is not as expected, finish the job and then clean and check the equipment. |
| ___ For broadcast sprays, ensure that foodstuffs are put away or covered with a sheet. |
| ___ Crack and crevice treatments result in a greater release of pesticide vapours than broadcast treatments. |
| ___ Generally, perimeter sprays suppress the activity of insects and provide only short-term control. |
| ___ Applications of pesticide dusts should be quite thick to be effective. |
| ___ Oil based insecticides can cause houseplant damage. |
| ___ When a rodent infestation is eliminated, there should be a plan to remove all bait from the client's property. |
| ___ Tenants with relevant medical problems should be allowed to opt out of a spray program. |
