APPLY PESTICIDES CORRECTLY
A GUIDE FOR COMMERCIAL APPLICATORS
FOOD PROCESSING
PEST CONTROL
U.S. ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF PESTICIDE PROGRAMS
WASHINGTON, D.C. 20460
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TABLE OF CONTENTS
Page
Acknowledgments 1
Preface 1
Introduction 2
Pests 2
Insects 2
Cockroaches 2
Stored Product Pests 2
Domestic Flies 4
Occasional Pests 5
Spiders and Mites 6
Centipedes 6
Rodents 6
Birds 6
Pest Control 6
Insects 6
Spiders and Mites 7
Centipedes 7
Rodents 7
Birds 8
Pest Treatment Areas in Food Plants 8
Incoming Ingredients and Materials
Storage Areas 8
Processing and Packaging Areas 9
Finished Products Warehouse and
Shipping Areas 9
Grounds 9
Pesticides 9
Aerosols 9
Liquids 9
Dusts 10
Granules 10
Baits 10
Fumigants 10
Vapors 12
1976
i
EFA ;:..:
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ACKNOWLEDGMENTS
PREFACE
This guide was developed by the University of
Minnesota under U.S. Environmental Protection
Agency (EPA) contract number 68-01-2651. This
contract was issued by the Training Branch, Opera-
tions Division, Office of Pesticide Programs, EPA.
The leader of this group effort was Phillip K. Harein,
University of Minnesota. Editors were Mary Ann
Wamslcy. EPA, and Donna M. Vermeirc, North
Carolina State University.
Contributors were:
Robert Davis, U.S. Department of Agriculture,
Savannah, Georgia
William M. Hoffman, Environmental Protection
Agency, Washington, D.C.
Darrell Jones, General Mills, Inc., Minneapolis,
Minnesota
Vernon E. Walter, Terminix International Inc.,
Memphis, Tennessee
Many representatives of the food processing indus-
try and food commodity associations reviewed and
commented on the guide.
Federal regulations establish general and specific
standards that you must meet before you can use
certain pesticides. Your State will provide material
which you may study to help you meet the general
standards.
This guide contains basic information to help you
meet the specific standards for pesticide applicators
in the food and feed industries. Because this guide
was prepared to cover the entire nation, some in-
formation important to your State may not be
included. The State agency in charge of your training
can provide the other materials you should study.
This guide will give you information about:
• characteristics of common pests,
• their life cycles and habits, and
• how to control them.
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INTRODUCTION
AMERICAN COCKROACH:
The control of pests in food plants (food manufac-
turing, processing, and warehousing) requires a high
degree of professionalism combined with experi-
ence and knowledge.
• Food plants must continually employ pest man-
agement programs.
* These programs must be directed against pests in
the immediate area, and against pests that may be
introduced from incoming materials.
• These programs must respond to daily needs and
be flexible to meet emergency pest control situa-
tions.
• Without good pest management, contaminated
products may result. Contamination can cause
serious health, financial, legal, and aesthetic prob-
lems.
PESTS
A variety of pests are found in food manufacturing
plants. The type of pest you will find depends on
both the geographic location of the plant and the
type of food being processed.
Pests may damage, destroy, or contaminate proc-
essed foods. They must be controlled to protect the
quality of the product. The presence or evidence of
pests may result in seizure of products or other
actions by Federal or State agencies.
INSECTS
Cockroaches
Cockroaches contaminate food with their droppings,
with their bodies, and with bacteria they carry. They
vary somewhat in appearance and habits, but in
general:
• All cockroaches have chewing mouthparts.
• They seek cover in the daytime or when disturbed
at night.
• All are flat, brownish or dark, and fast-running.
The stages in the life cycle of a cockroach are:
• the egg, enclosed in a capsule which contains
several eggs,
* several stages of nymphs, which look like the
adults but are smaller and have no wings, and
* the adult.
• Adults have wings covering the entire abdomen.
• Reddish-brown.
• Adults 1 to I '-'2 inches long.
• Found in dark, moist areas and may live in
sewers.
GERMAN COCKROACH:
Adults have wings covering entire abdomen.
Tan with two dark stripes running lengthwise on
the area just behind the head.
Often occur in large numbers.
Will eat almost any food consumed by man.
Adults 1 to 11/2 inches long.
More active than other cockroaches.
ORIENTAL COCKROACH:
• Female has small wings; male's wings cover about
*'j of the abdomen.
• Shiny black, or very dark brown.
• About 1 inch long as an adult.
• Often lives in sewers and enters buildings through
drains.
American Cockroach Oriental Cockroach
Stored Product Pests
Beetles are important pests of stored food. Usually
both the larva and the adult will feed on food-
stuffs. Under ideal conditions they can have six or
more generations per year and quickly become a
serious problem. Adults may have a pair of thin
wings covered by a pair of thick, hard wings.
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The stages in the life cycle of the beetle are:
• egg,
• larva,
• pupa, and
• adult.
RICE WEEVIL—GRANARY WEEVIL:
About VH inch long; dark brown.
Pronounced snouts.
Larvae arc small, white, legless grubs that feed
and develop inside individual kernels of grain.
May attack grain prior to harvest and in storage.
Rice weevil can fly; granary weevil cannot fly.
Granary Weevil
LESSER GRAIN BORER:
Rice Weevil
Shiny dark brown or black beetle.
Small and slender.
Head turned downward; very strong mouthparts
which can cut through wood.
Adult is a strong flier.
Larvae feed on flour, grain dust, or broken or
whole grain.
CONFUSED FLOUR BEETLE—RED FLOUR
BEETLE:
• Elongated, flat adults, about Vs inch long.
* Shiny, reddish-brown.
• Feed on stored foods such as flour, cereal, nuts,
and spices.
• Feed by scraping the surface of foods or eating
finely ground material.
• Red flour beetle is a strong flier; confused flour
beetle cannot fly.
• The three segments at the tip of the red flour
beetle's antennae are enlarged. The antenna seg-
ments of the confused flour beetle enlarge grad-
ually toward the tip.
Red Flour Beetle
SAWTOOTHED GRAIN BEETLE-
MERCHANT GRAIN BEETLE:
Elongated, flat adults, about V» inch long.
Dark brown.
Adults have sawtooth-like projections on
of area just behind the head.
Do not fly.
Feed on almost all dried foods.
Saw-Toothed Grain Beetle
sides
DRUGSTORE BEETLE—CIGARETTE BEETLE:
• Small, reddish-brown adults, usually less than Vs
inch long.
• Head on adult bent down and not visible from
above.
• Feed on dried plant and animal material.
• Cigarette beetle can fly; drugstore beetle seldom
flies.
• Wing covers lined on drugstore beetle; smooth
on cigarette beetle.
Cigarette Beetle
DERMESTID BEETLES:
• Oval-shaped beetles which feed on waste grain
or flour.
• Natural scavengers.
• Several species.
• Larvae are tapered, with head at the large end.
• Prominent bristles or hair often found at pointed
end of larva.
• Larvae feed on dry grain dust, waste matter, or
flour.
Khapra Beetle Adult
Khapra Beetle Larva
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Mediterranean Flour Moth
Moths cause damage by:
• eating food,
• contaminating food to the point where it cannot
be consumed by humans, and
• webbing food with so much silk that mill ma-
chinery may be clogged. Large populations may
lead to microorganism problems.
The stages in the life cycle of the moths are:
• egg,
• larva,
• pupa, and
• adult.
ANGOUMOIS GRAIN MOTH:
• Adults have four wings; about '/2 inch wing- WAREHOUSE MOTH:
spread.
• Forewings are pale yellow. Hind wings are gray
and pointed.
Larvae develop within whole kernels of grain.
May attack grain before harvest as well as in
storage.
Pupa found inside grain.
Six to seven generations per year.
When they emerge, they leave a round flap over
the hole in the grain.
Front wings are gray with dark wavy lines.
Adults rest with head and thorax held high.
Larvae feed on surface of food, and spin large
amounts of silk in and over it.
Three to four generations per year.
Larvae leave feeding area to pupate.
Prefers flour but infests wheat, bran, nuts, choc-
olate, seed, beans, and dried fruits.
• Adult's forewings are gray.
• They fly in a series of quick darts.
• Habits similar to the Mediterranean Flour Moth.
• Larvae striped with a series of brown or .purple
dots.
Domestic Flies
Angoumois Grain Moth
INDIAN MEAL MOTH:
Adults have four wings, with a wingspread of
about l/2 inch.
Forewings have a coppery color on the outer two-
thirds and whitish gray near the body.
Larvae spin large amounts of silk in and over
food.
Larvae may leave food and crawl over adjacent
surfaces.
Five to six generations per year.
Prefers flour but feeds on many raw and proc-
essed dry foods.
Indian Meal Moth
MEDITERRANEAN FLOUR MOTH:
• Adults have four wings, with a wingspread of
about % inch.
Most flies have one pair of wings as adults. The
larvae are called maggots and have the head at
the small pointed end of the body. Larvae have no
legs.
The life cycle of the fly includes:
• egg-
• larva,
• pupa, and
• adult.
BLUE BLOW FLY:
• Area behind the head gray with stripes. Abdo-
men shiny blue.
• Slightly larger than housefly.
• Common during early spring.
• Life cycle is 2-3 weeks.
• Attracted to decaying flesh.
GREEN BLOW FLY:
• Body shiny green or copper.
• Slightly larger than housefly.
• Garbage is common breeding area.
• Often comes from nearby residential areas or
farms.
• Life cycle is 9-18 days.
• Common during summer months.
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HOUSEFLY:
• Adults dull gray with four stripes on area behind
the head.
• About V* inch long as adult.
• Most abundant in fall, but may be found through-
out the year.
• Larvae occur in animal waste or rotting fruits
and vegetables.
• Life cycle is 1-6 weeks.
House Fly
FRUIT FLY (VINEGAR FLY):
• Adults about '/» inch long and yellowish brown.
• Attracted to sour or pungent odors.
• Adults often found around overripe fruit or vege-
tables.
• Life cycle is 8-11 days.
* Eggs often laid on cracks in tomatoes and similar
foods.
Occasional Pests
ANTS:
• Only adults are normally seen.
• Eat many foods but prefer sweets and grease.
• Most species have winged stage once a year.
• Most come in from outside, but a few species
nest in walls.
Ant
The stages in the life cycle of an ant are:
* egg,
• larva,
• pupa, and
• adult.
BRISTLETAILS (SILVERFISH, FIREBRATS):
• Gray, silver, or brownish adults, about Vi inch
long.
• Young resemble adults but are smaller.
• Silverfish like high humidity; firebrats prefer low
humidity and high temperature.
• Can live a year or more without food.
• Often found in warehouses, where they may dam-
age paper and starch products.
Bristle Tail
/
The stages in the life cycle of silverfish and firebrats
are:
• the egg,
• nymphs, and
• adult, which continues to molt throughout its
life span.
BOOKLICE (PSOCIDS):
• Very small (^n-Mo inch).
• Young resemble adults.
• Normally live in moist areas and feed on fungi.
• May be carried into food manufacturing plants
on infested pallets and cardboard slipsheets.
• Have been found in newly manufactured empty
containers.
Booklouse
Life cycle takes a little over a month. The stages
are:
• egg,
• nymph, and
• adult.
CRICKETS:
• Winged adults are attracted to lights in summer-
time.
• May stray into food manufacturing plants and
contaminate food.
• May eat holes in paper, cloth, or rubber.
• Large hind legs adapted for jumping.
Stages in the life cycle are:
• egg,
• nymphs, and
• adult.
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SPIDERS AND MITES
• Spiders are usually just a nuisance, but the black
widow and brown recluse are poisonous.
• Spiders are more commonly found in ware-
houses than in production areas.
• Webs, bodies, and excretions of spiders can be
a nuisance.
• Presence of spiders may indicate an insect infes-
tation problem.
• Mites are extremely small.
• Some mites contaminate food.
• A heavy infestation of mites produces a pro-
nounced pungent odor.
• Mites may cause skin rash to humans and diges-
tive disturbance if eaten.
CENTIPEDES
• Has many legs—one pair per segment.
• Beneficial and eats insects, but may contaminate
food.
* Large populations are associated with moisture
and decaying vegetable matter.
• May enter from outside.
* May frighten some workers, but not poisonous.
RODENTS
Contaminate and destroy food products.
Damage equipment, structures, and other non-
edible items.
May carry diseases and ectoparasites.
Can cause fires.
Have the ability to coexist with man.
The three most common kinds are:
• Norway, brown, or common rat,
• roof or black rat, and
• house mouse.
Field Identification of Domestic Rodents
ROW RAT Rottui ro«i» TOUNC "*T
EAR Er€ NOSE
!"Ul. • HLV.T
FEET HEAD
HOUSf MOUSE
Mm nvtcului
NORWAY RAT Ratlus nontgkvi
The Norway rat prefers to live in underground bur-
rows, but can climb readily. The roof rat prefers to
live in upper portions of a building, but may use
burrows. The house mouse lives in any convenient
protected space inside or outside.
BIRDS
Only three species of birds—English sparrows,
pigeons, and starlings—are normally considered pests
around food manufacturing plants. They are pri-
marily objectionable because:
• Their feathers and droppings can contaminate
food.
• They may spread diseases.
• They may ruin roofs and gutters and deface build-
ings with their droppings.
• They sometimes carry mites which can bite man.
PEST CONTROL
INSECTS
Cockroaches
Continual removal of food and water sources and
destruction of breeding places are essential in obtain-
ing satisfactory cockroach control. Apply insecti-
cides as crack and crevice or spot treatments to
places where the insects hide. Follow label direc-
tions for commercial food handling areas.
Common hideouts are behind and beneath built-in
equipment, beneath trash, in floor drains, sewers,
and in cracks and crevices in concrete, brick, or
block walls. Sprays are usually preferred to dusts
because they are easier to apply and the residue is
not visible. Dusts, however, can sometimes be blown
into places difficult to reach with spray.
Use ULV (ultra low volume) concentrates and aero-
sol applications of contact sprays and flushing agents
to supplement residual sprays and dusts. Use them
alone where the label prohibits use of residuals.
Stored Product Pests
To eliminate infestations, find and destroy infested
materials and treat the area where they are stored.
Some infested materials can be treated with cold or
heat or fumigated. Thorough cleaning is essential
to remove spilled food to prevent reinfestation.
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Domestic Flies
Successful fly control must include a combination of
sanitation measures, mechanical lures (electric grids),
physical barriers (screens or air curtains), and insec-
ticides. The plant and surrounding area should be
kept free of garbage, manure, and decaying plant or
animal matter. Continual removal of solid and liquid
process wastes is essential to prevent the formation
of breeding sites. Control adults by spraying resting
places with the use of aerosols or ULV concentrates.
Baits can be used to treat breeding sites.
Ants
Control ants by direct treatment of their nests. Dusts
can be used on outdoor-nesting ants. For control
of indoor-nesting ants, use formulations that will
not move far from the spray site. Follow label
directions. Sprays or granular insecticides can also
be used on the nests and surrounding area. If you
cannot locate the nest site, apply insecticides where
the ants gain entry or hide—along foundation walls,
at doorways, windowsills, baseboards, or behind or
beneath equipment.
Brisdetails
Directed sprays applied to cracks and crevices that
serve as hiding and resting places are most frequently
used for control; dusts and baits may also be used
as well as aerosols and ULV concentrates.
Booklice
Remove moisture and food sources. Directed sprays
and aerosols are effective in control.
Crickets
Remove trash piles and tall weeds. If a dump or
similar area is a breeding place, cover it with 6
inches of soil or ashes. Outdoor sprays give only
temporary control. Inside, spray residual pesticide
in areas where crickets have been seen.
SPIDERS AND MITES
Control insects that serve as food, and remove webs.
Direct pesticide sprays or dusts at hiding areas.
CENTIPEDES
Remove sources of moisture and decaying vegetable
matter. Use wettable powders or emulsifiable con-
centrates of residual pesticide in a 2- to 3-foot strip
around the outside of the building. Treat suspected
breeding sites by applying the pesticide with enough
water to carry it down to where the pests live.
RODENTS
A rat or mouse control program is based on know-
ing:
• where they live, feed, and travel, and
• the extent of the infestation.
You must eliminate shelter, food, and water. Close
all entrances the rats or mice use to come and go
from buildings. These preventive measures are the
key to successful control. To prevent rodent migra-
tion, it is best to poison or trap before making
environmental changes.
The two categories of rodenticides are:
• multiple-dose anticoagulants, and
• single-dose poisons.
Each rodenticide has special characteristics, u$es,
and hazards. Some are highly toxic to humans and
pets. Mix, handle, and apply them according to label
directions.
Place bait deep into burrows or use bait stations.
Keep them away from people and desirable animals.
Dispose of excess baits and dead animal carcasses
at frequent intervals.
Mice will eagerly sample new food. Rats, however,
usually approach new food with caution. If it tastes
bad or makes them sick, they will not eat it again.
This is "bait shyness". When using bait for control,
use a bait that is fresh and identical to the food
the rats are using. If you use a different bait base,
prebait in the area for a few nights before using
a toxic bait. Alternate anticoagulants with single-
dose poisons to reduce possibility of the develop-
ment of resistance. Certain baits may attract insects
and should be replaced often.
Rats require water to drink. Mice may get water
from the food they eat. If all water sources can be
eliminated, liquid baits are very effective for rats
but only moderately so for mice.
Both rats and mice prefer to run next to walls or
other surfaces. Place traps and baits in these run-
ways. Traps may be used with bait, or the trigger
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device may be expanded and used without bait. Rats
approach new objects cautiously.
The mouse investigates any new object or change in
its territory, so changing placement of baits or traps
may improve control. Each house mouse establishes
a territory which may not extend more than 10 feet
from the nest. For this reason, baits and traps should
be placed no more than 10 to 20 feet apart.
Be aware of nearby environmental disruptions that
may cause rodents to enter buildings.
BIRDS
Sanitation is the first step in control. Remove food,
water, and habitat. Control methods include build-
ing out, removing food, and using repellents, traps,
or avicides.
Building out involves using new construction features
or modifying existing features so that birds cannot
roost or nest.
Repellents include various devices or substances in-
stalled in potential bird roosting and nesting areas.
They include revolving lights, noise makers (distress
calls), charged wires, and repellent glues or jellies.
Traps are often used successfully in pigeon control.
especially when prebaited for a few days. Release
any birds that are protected by law from such control
methods.
Population reduction includes shooting (where per-
missible) and the use of avicides. Chemical control
is probably the most effective method. Follow label
directions closely. Know your city, county, State,
and Federal regulations.
PEST TREATMENT AREAS
IN FOOD PLANTS
Food plants have five areas of activity where pests
must be controlled:
• receiving and storage area for incoming materials,
• processing area,
• packaging area,
• finished product warehouse and shipping area, and
• grounds—the building exterior and the area
around the plant.
Both chemical and nonchemical controls are im-
portant in these areas. Nonchemical controls include
both preventive maintenance and mechanical and
physical measures.
Pests may enter the plant in two ways:
• by slipping by the outside control programs, and
• by coming in with ingredients or materials.
Some nonchemical control methods that apply to
all areas inside a plant are:
• Rodent-proofing and bird-proofing doors, walls,
windows, and roofs.
• Screening all windows that can be opened.
• Eliminating cracks, crevices, and other places
where pests may hide.
• Whenever possible, locating equipment off the
floor and away from walls or sealing it to walls
and floors.
• Keeping the building clean and free of litter.
• Keeping the inside and outside of all equipment
clean.
• Using light traps for insects.
INCOMING INGREDIENTS AND
MATERIAL STORAGE AREAS
Xonchemical Controls
• Visually inspect all vehicles, ingredients, and ma-
terials to insure that pests are not brought into
storage areas.
• Store ingredients and materials far enough away
from walls to permit access for inspection.
• Use FIFO (first in-first out) rotation of incoming
materials.
• Use traps or other methods for rodents.
• Use air curtains at dock and pedestrian doors to
keep insects out.
• Use mechanical repellents for birds.
Chemical Controls
INSECTS:
• Space treatment with nonresiduals.
• Crack and crevice treatment with residuals.
• Spot treatments with residuals.
• Periodic general treatment.
• Treatment of raw bulk commodities with fumi-
gants and sprays on receipt and during storage
where applicable.
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RODENTS'.
• Bait stations.
PROCESSING AND PACKAGING
AREAS
Nonchemical Controls
• Place rodent traps near doors if situation warrants.
Chemical Controls
INSECTS:
Space treatment with nonresiduals.
Spot treatment with nonresiduals.
Crack and crevice treatment with residuals.
Contact treatment with nonresiduals.
Periodic general treatments.
FINISHED PRODUCTS
WAREHOUSE AND SHIPPING
AREAS
Use the same pest control methods in the finished
products warehouse as in the materials receipt and
storage area.
Vehicle inspection is essential to prevent the finished
products from being placed in a pest-contaminated
carrier. Vehicle inspection is difficult, particularly
for boxcars and trucks with false walls or endliners.
If vehicles are dirty or infested, do not use them.
Chemical Controls in Vehicles
Before loading, consider:
• space treatment, or
• crack and crevice treatment.
After loading, use:
• general treatment—usually a solid fumigant—for
in-transit control.
GROUNDS
Nonchemical Control
• Eliminate all exposed dirt surfaces by paving all
roadways or parking areas and maintaining well-
kept lawns. This will reduce contamination from
dirt, microbes, and other airborne particles.
• Provide good drainage to help keep the area
clean and dry.
• Place outside lighting away from buildings and
focus the lights toward buildings. This helps keep
night-flying insects away from doors and windows.
• Screen potential bird roosting areas.
• Store equipment so that it does not become a
place for pests to hide.
• Remove all litter, weeds, and grass clippings.
• Eliminate any waste that may accumulate near
exhaust systems.
• Use rodent, insect, and bird traps as necessary.
Chemical Control
• Baits for rodents.
• Baits, fogs, and sprays for insects.
• Chemical repellents or avicides for birds.
PESTICIDES
AEROSOLS
ADVANTAGES:
• Excellent for flying or exposed insect pests.
• Disperse well if used correctly.
• Convenient and easy to store.
• Usually leave little surface deposit.
• Store well during normal use period.
• Available for hand operations or can be installed
as a timed release system.
LIMITATIONS:
• No lasting protection.
• Good only for exposed pests.
• Hazardous if container is punctured or over-
heated.
• Usually cannot be used during food processing or
when people are present,
LIQUIDS
ADVANTAGES:
• Usually provide a deposit on surface.
• Can be easily directed onto surface for treatment.
• Easy to store, transport, and handle.
• Adaptable for use in many kinds of equipment.
LIMITATIONS:
• May be hazardous to use around electrical outlets
(water or oil sprays).
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May damage or stain wallpaper, varnish, and FUMIGANTS
many fabrics (water or oil sprays).
May leave unsightly residue (wettable powders).
Require agitation during application (wettable
powders and emulsions).
May be hazardous around open flames (oil
sprays).
May damage or etch asphalt, plastic tile, or rub-
ber products (oil sprays).
May make floors slippery (oil sprays).
May damage living plants (oil sprays).
Fumigants penetrate cracks, crevices, and the com-
modity being treated. They must reach the target
pests as gases to be effective. As soon as a fumigant
diffuses from the target area, reinfestation can occur.
Fumigants must be applied in enclosed areas.
Types of Fumigation
Types of fumigation are:
DUSTS
ADVANTAGES:
• Excellent for crack and crevice treatments.
• May be purchased ready-to-use.
• Usually require only simple and lightweight ap-
plication equipment.
• Safe for use around electrical equipment.
surface (should
or above food-
LIMITATIONS:
• Drift easily.
• Easily dislodged from treated
not be applied on equipment
contact surfaces).
• Generally bulky to store.
GRANULES
ADVANTAGES:
• Ready-to-use.
• Do not drift.
LIMITATIONS:
• Can he used only on fairly level surfaces.
• May be tempting to nontarget animals.
BAITS
ADVANTAGES:
• Can often control specific pests.
• Easily distributed.
• Easily monitored and recovered.
* Used in small amounts.
LIMITATIONS:
* Can be dangerous to nontarget animals.
• Often not as attractive as natural food supply.
• Rodents must feed for 5 to 15 days on an anti-
coagulant rodenticide before it is lethal.
* Rodents feeding on poison baits may die any-
where and go undetected, causing sanitation prob-
lems.
general fumigation (buildings and their contents),
• spot fumigation (machinery, facilities, bulk com-
modities),
• tarpaulin or chamber fumigation (packaged com-
modities), and
• vehicle or in-transit fumigation (trucks, ships, and
railway boxcars).
Selection of Fumigants
When choosing a fumigant, consider:
• toxicity to the target pest,
• volatility and ability to penetrate,
• corrosive, flammability, and explosive potential,
• warning properties and detection methods,
• effect on seed germination and finished product
quality,
• residue tolerances,
• availability,
• ease of application, and
• cost.
Several factors can change the efficiency of fumi-
gants. Consider these when selecting a formulation
and dosage:
Temperature—The fumigant may not kill the pests
if the product or space being fumigated is below
10°C(50° F) or above 46° C( 115° F).
Moisture—As the moisture content of a commodity
increases, it becomes more difficult for a fumigant
to penetrate it. This also increases the potential for
residues exceeding legal tolerances. Adequate mois-
ture is required for the generation of some fumi-
gants.
Pests—Susceptibility to fumigants depends on spe-
cies, habitat, and stage of development. During some
stages of their life cycle, for example, many insects
are protected by the product they infest.
Structure—Consider the condition of the structure,
the type of construction, and the product it contains.
10
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A wooden structure, even when sealed well, will not
retain fumigants as well as metal, plastic, masonry,
or concrete. Fumigation in vacuum chambers allows
increased efficiency.
Method of Application—Fumigants are widely used
because they can be applied in many ways. Fumiga-
tion techniques include:
• Applying solid or liquid formulations to streams
of bulk grain.
• Applying liquid formulations to the surface of
grain. The vapors flow down through the grain
either by gravity or by forced distribution with
bin aeration systems.
• Piping liquid or solid formulations into a grain
mass to eliminate local infestations.
• Using spot fumigation in structures or in machin-
ery or products.
Preparing for Fumigation
Understand fully the facility and commodity to be
fumigated, including the:
• design of the structure, as well as adjacent and
connecting structures both above and below
ground,
• persons or animals expected to be at or near the
area to be fumigated,
• the commodity, its history and condition (previous
fumigation, temperature, moisture),
• availability of emergency shutoff stations for elec-
tricity, water, and gas,
• location of nearest telephone, and numbers for
fire or police departments, hospitals, and physi-
cian.
Select a suitable fumigant.
Understand label directions, warnings, and antidotes.
You may need to notify local medical, fire, and
police authorities and other security personnel
about:
• chemicals to be used,
• proposed date and time of use.
• type of gas masks required,
• fire hazard rating, and
• name and phone number of person to contact
in event of emergency.
Have alternate application and protective equipment
and replacement parts available. Display warning
signs near points of entry and provide for security
of buildings. Have necessary first aid equipment
available. Before treatment is started, develop plans
to ventilate the area when the treatment period is
over.
Application
Always assign two persons to each fumigation.
Everyone involved in the fumigation should know
first aid and other emergency procedures, including
personal decontamination.
Follow label directions exactly when applying a
fumigant. Consider prevailing winds and other per-
tinent weather factors such as temperature and
humidity. Apply fumigants from outside the exposed
areas wherever possible.
Inspect all valves, gauges, and in-plant piping be-
fore using built-in fumigation system where fumi-
gant source may be either inside or outside the area
being treated.
Return to the storage area all unused chemicals in
clearly labeled, original containers. Dispose of
empty containers correctly.
Provide watchmen, when required. Entrances should
be secured by guards or locks.
Report to company-retained physician or to desig-
nated personnel, indications of illness or physical
discomfort, no matter how minor they seem. These
symptoms and signs may include: dizziness, nausea,
headaches, and lack of coordination.
Do not consume alcohol for 24 hours before or
after a fumigation.
After Application
Before reentry, use a suitable gas detector, as indi-
acted on the label, to determine fumigant concentra-
tion. Do not depend on odors. Some fumigant gases
are odorless. Wear correct respiratory equipment.
Turn on all ventilating or aerating fans.
Check for gas concentrations in areas that are ex-
pected to aerate slowly.
Remove warning signs when the gas concentration
is within safe limits for human exposure.
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Remove and dispose of packaging and waste prod-
ucts of solid fumigants.
Fumigants are useful but have specific advantages
and limitations.
ADVANTAGES:
• Toxic to many pests.
0 Can be applied by various methods,
• Easy to apply without disturbing the commodity.
• Penetrate structures, commodities, and equipment.
• Readily available and economical.
DISADVANTAGES:
• Toxic to humans.
• Require trained applicators.
• Target area or commodity must be enclosed.
• May injure seed germination.
• Temperature requirements may be hard to meet,
especially in northern climates.
VAPORS
Vapors are volatilized by supplementary heat or by
inherent high vapor pressure to produce a gas. They
are usually dispersed from impregnated resin strips,
or vaporizers.
ADVANTAGES:
• Easy to apply and safe to handle.
• Can be used where fumigant tolerances may be
exceeded.
• Sealed building not as essential as for fumigants.
• Effective against flying insects such as moths
and flies.
DISADVANTAGES:
• Will not penetrate commodities in concentrations
lethal to target pests.
• Resin strips cannot be used in plant areas where
food is exposed.
* US. GOVERNMENT PRINTING OFFICE 1S76- 210-810/162
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