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January 27, 2016

Antimicrobial Pesticides Use Site Index 

I. Introduction

The Environmental Protection Agency (the Agency) codified twelve antimicrobial use patterns in 40 CFR 

part 158, subpart W (referred to as “Part 158W”). The Agency has developed an Antimicrobial Pesticide 

Use Site Index (USI) to provide guidance about the antimicrobial pesticide use sites associated with these 

antimicrobial pesticide use patterns. The USI is a guidance document to assist applicants in identifying 

the data that are necessary to support registration of products and to determine if labeled uses necessitate 

establishment of a tolerance or exemption from the requirement of a tolerance. As noted in 40 CFR 

Section 158.100(d), the USI will be updated periodically, as needed.

The association of a particular antimicrobial use site with an antimicrobial pesticide use pattern should be 

viewed as a recommendation only and is not to be construed as binding on either EPA or any outside 

parties. EPA may depart from the guidance where circumstances warrant and without prior notice. 

Pesticide product labeling provides critical information about pesticide use sites, as well as how to safely

and effectively handle and use pesticide products. In order to ensure no unreasonable adverse effects on 

human health or the environment, FIFRA and its regulations require, among other things, that product 

labeling specifically states where and how a pesticide is intended to be used. Where a pesticide is to be 

used is generally referred to as the “pesticide use site.” For antimicrobial pesticides, the use sites are 

diverse and constantly evolving as new products are developed. The USI serves as a guide to the general 

types of use sites that are commonly listed on antimicrobial labels. It is not intended as an exhaustive list

of all possible antimicrobial use sites. The use sites are organized into twelve use patterns which are used 

to delineate data requirements in Part 158W. 

Furthermore, the use sites associated with the twelve use patterns are organized into three food use

categories: direct food uses, indirect food uses, and nonfood uses. A number of the data requirements in 

subpart W depend on this categorization. The categorization is dependent on the context of the label and 

a determination of whether residues of the pesticide product have the potential to come into contact with 

food, either directly or indirectly. For example, within the use pattern Residential and Public Access 

Premises, the use site of Household/Domestic Dwellings is listed under both the indirect food use 

subcategory as well as the nonfood use subcategory. Specifically, there are two use sites:

Household/Domestic Dwellings (food handling areas), listed under “indirect food,” and

Household/Domestic Dwellings (non-food handling areas), listed under “nonfood”. This reflects the fact 

that within the use site category of Household/Domestic Dwellings, there is a potential for indirect food 

contact for some uses (e.g., if a product is labeled for use on kitchen countertops), but there are also uses 

within this category that would be considered nonfood (e.g., a product labeled for use as a toilet bowl 

disinfectant). The categorization of the use sites on the product label determines whether or not certain 

data requirements must be addressed.

To aid applicants, the descriptions of the food use categories, direct food, indirect food, and nonfood are 

listed below. Food has the same meaning as the Federal Food, Drug, and Cosmetic Act at 21 U.S.C. § 

321(f): (1) articles used for food or drink for man or other animals, (2) chewing gum, and (3) articles used 

for components of any such article.
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Direct Food Use

A use is generally considered to be a direct food use if an antimicrobial pesticide is intended to be directly 

applied to food or applied to a material or article for the purpose of treating food. Use sites that fall into 

this category include, but are not limited to: fruit and vegetable rinses, fogging of poultry areas, and egg 

washing treatments. These types of uses are generally subject to a FFDCA clearance. 

Indirect Food Use

A use is generally considered to be an indirect food use if the use involves application of the antimicrobial 

pesticide in or on a material or article that comes into contact with food and may result in residues in or 

on food, but the use is not intended for pesticidal treatment of food. As a result of contact with a surface 

and/or material that has been treated and/or impregnated with an antimicrobial pesticide, there is a 

potential for transfer of residues in or on food. Use sites that fall into this category include, but are not 

limited to: sanitization of food-contact dishes, utensils, food-processing equipment, and countertops; 

disinfection of food-use areas; and impregnation of cutting boards, conveyor belts, or food containers 

and/or packaging for a pesticidal purpose other than treating food (e.g., to protect the article itself from 

degradation by bacteria). These types of uses may be subject to a FFDCA clearance. 

Nonfood Use

A use is generally considered to be a nonfood use if the antimicrobial pesticide is not expected to come 

into contact (directly or indirectly) with food as a result of its intended use and, therefore, there is no 

reasonable expectation of residues in/on food. Use sites that fall into this category include, but are not 

limited to: fuel tanks, human footwear, or nonfood areas (e.g., under the sink) of eating establishments. 

These types of uses are not subject to a FFDCA clearance.

II. How to Use this Use Site Index to Determine Data Requirements

The applicant should follow these basic steps for using the Use Site Index:

1. Look for use sites in the USI that are similar to your proposed uses. 

2. Identify which of the use patterns applies to your proposed uses.

3. For ecological data requirements, consult the Nontarget Organism, Nontarget Plant Protection, and 

Environmental Fate Data Requirement Tables in Part 158W to determine data required for each 

use pattern. For example, Guideline Number 850.3020, Honeybee Acute Contact Data, are 

Required (R) for Wood Preservatives, Not Required (NR) for Industrial Processes and Water 

Systems and Antifoulant Paints and Coatings, but Conditionally Required (CR) for the All Other 

Use Pattern Categories. 

4. For human health (toxicology and residue chemistry) data requirements, determine the food use 

category of your proposed uses by:

a. Identifying whether your proposed use sites are characterized as “direct food”, “indirect 

food”, or “nonfood” based on the designation of the similar use sites listed in the USI. 

b. Applying the guidance in Section III (Figure 1. Food Use Description Flow Chart) to the 

proposed uses to determine whether a tolerance/tolerance exemption is needed.

5. For exposure data requirements, consult the Antimicrobial Applicator Exposure Data 

Requirements table and the Antimicrobial Post-Application Exposure Data Requirements tables to 

determine the data required according to whether the use pattern is associated with occupational or 

residential exposure. 
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III. How to Determine Required FFDCA Clearances

This USI provides guidance on whether a use site on a product label will necessitate establishing a 

tolerance or tolerance exemption (see Figure 1).

FFDCA clearances will be required where there is a reasonable expectation of residues in or on food as a 

result of application (either directly or indirectly) of the pesticide to food and the food moves in interstate 

commerce. For a substance that meets the definition of “pesticide chemical residue” under FFDCA 

section 201(q), a tolerance or exemption from the requirement of a tolerance will be required; for a 

substance that is excluded from that definition, the US Food and Drug Administration (FDA) may need to 

issue a food additive regulation or food contact notification. Regardless of the classification under 

201(q), residues of pesticides in or on foods will cause foods to be considered adulterated and subject to 

seizure if appropriate FFDCA clearance(s) are not in place (i.e., a tolerance, tolerance exemption, FDA 

food additive regulation, and/or food contact notification (FCN)). See 21 U.S.C. §§ 334, 342, 346a, and 

348. 

EPA has made it a requirement of FIFRA registration that, if a pesticide bears directions for use on food 

or may be reasonably expected to result in residues on food which moves in commerce, all necessary 

FFDCA clearances must be in place. 40 C.F.R. § 152.112(g). Because direct food use pesticides, by 

definition, contain label directions for use on food, all necessary clearances under the FFDCA must be in 

place to obtain FIFRA registration. Because indirect food uses are generally considered to have a 

reasonable expectation for residues on food, all necessary clearances under the FFDCA also must be in 

place to obtain a FIFRA registration. However, EPA will not require that FFDCA clearances be obtained 

for indirect food uses if an applicant can demonstrate that the use(s) of a particular product do not have a 

reasonable expectation of resulting in residues on food. No FFDCA clearances are required for nonfood 

uses because there is no reasonable expectation of residues on food for these uses.

Figure 1 below assumes that a determination under FFDCA section 201(q) has been made and the 

residues in/on food would meet the definition of pesticide chemical residues. Therefore, EPA would have

jurisdiction under FFDCA section 408 to determine if a tolerance or exemption from the requirement of a 

tolerance is needed. For residues that do not meet the definition of “pesticide chemical residue” and are 

under the jurisdiction of FDA under FFDCA section 409, EPA still must make a safety finding by 

conducting any appropriate dietary exposure assessments if the residues result from the use of FIFRAregistered pesticides. This flow chart is not designed to delineate jurisdiction under FFDCA between 

EPA and FDA.
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Figure 1. Food Use Description Flow Chart

No data required to support 

a dietary assessment 

Direct 

Food Use

Indirect 

Food Use

Nonfood 

Use

Are residues expected 

in/on food for this use?

Are residues expected 

in/on food for this use?

No residues expected 

in/on food for this use

No

Yes 

Is the use strictly residential?

No Yes 

Data are necessary to 

support a dietary exposure 

assessment conducted for 

safety finding (FIFRA)

A tolerance or exemption from the 

requirement of a tolerance is needed

No tolerance or exemption from the 

requirement of a tolerance is needed

Registrant must 

provide an 

adequate 

rationale and/or 

demonstrate that 

there is no 

reasonable 

expectation of 

residues in/on 

food*

*Examples of rationale include but are not limited to:

• Data and/or rationale used to support FDA food 

additive regulation or FCN

• Theoretical high-end calculations/modeling 

demonstrating that there is no reasonable 

expectation of residues in/on food

• Data/justification of residue removal via a 

potable water rinse 

• Label restrictions limiting exposure to food

• Justification based on product chemistry and/or 

environmental fate characteristics (i.e., volatility, 

solubility)

• Residue data
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IV. Use Site Index

Food Uses Nonfood Uses

Direct Food Uses Indirect Food Uses

1. Agricultural Premises and Equipment

−Irrigation Systems 

(Food crops)

−Animal Drinking Water

−Animal Premises/Structures/Buildings/ Equipment

−Beehives (honey producing)

−Dairy Farm Milk Handling 

−Empty Containers or Equipment to Be Used for Raw

Agricultural Commodities

−Facilities/Equipment

−Fish Hatchery Buildings/Areas (Nonaquatic)

−Food/Feed Storage Premises 

−Greenhouses (Food Crops)

−Agricultural/Farm Premises/Structures/Buildings/ Equipment

−Beehives (non-honey producing, such as pollinators)

−Egg Handling Equipment/Rooms/Washing/Treatments (Hatching)

−Greenhouses (Nonfood crops)

−Irrigation Systems (Nonfood crops)

−Shoe Baths

−Tobacco Processing Plant Premises/Equipment

2. Food Handling/Storage Establishments, Premises and Equipment

−Egg Washing 

Treatments 

−Fruit and Vegetable 

Treatments

−Dairies/Cheese Processing Plant Premises/Equipment 

−Dishwashing Water

−Eating Establishments/Equipment/Utensils/Food 

Handling/Serving Areas 

−Egg Handling Equipment/Handling Rooms/Packing Plants 

−Feed Mills/Food Processing Plants Premises and Equipment

−Food Processing Water Systems

−Transportation/Facilities/Barges/Railroad Cars/Commercial 

Shipping Containers

−Eating Establishments (Nonfood areas)

−Food Processing Plant Premises/Equipment (Nonfood)

−Hydrostatic Sterilizer Water Systems

−Pasteurizer/Warmer/Cannery/Retort Water Systems

3. Commercial, Institutional and Industrial Premises and Equipment

Not Applicable Not Applicable −Barber/Beauty Shop Equipment/Instruments 

−Commercial Transportation Vehicles/Facilities 

−Heating, Ventilation, and Air Conditioning (HVAC) Systems 

−Laundry/Laundry Equipment

−Premises/Equipment 

−Refuse/Solid Waste Transportation Facilities/Handling Equipment 

4. Residential and Public Access Premises

Fruit and Vegetable 

Treatments

−Household/Domestic Dwellings 

(Food Handling Areas such as kitchens) 

−Air Treatments 

−Animal Kennels/Pet Living/Sleeping Quarters

−Automobiles, Taxis, Limousines, Recreational Vehicles (RVs) 

−Bathroom Premises

−Clothing/Laundry 

−HVAC Systems and Humidifiers
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Food Uses Nonfood Uses

Direct Food Uses Indirect Food Uses

−Public Areas Contents/Premises

−Household/Domestic Dwellings Contents/Premises (non-food handling 

areas such as bathrooms)

−Paths/Patios/Paved Areas

−Public Areas Contents/Premises 

−Refuse/Solid Waste Containers/Equipment/Facilities/Sites

−Toilets (Urinals, Latrines, Water Closets) 

5. Medical Premises and Equipment

Not applicable Not applicable −Air Treatments 

−Ambulances

−Hospitals/Medical Institutions (Human/Veterinary nonfood handling areas)

−Critical and Noncritical items (patient care items and noncritical 

environmental surfaces)

−Medical Waste

−Morgues/Mortuaries/Autopsy/Embalming Room Premises/Equipment

−Nursing Homes/Assisted Living Facilities (nonfood handling areas)

6. Human Drinking Water Systems

Not applicable Not applicable −Dental water lines

−Emergency Water Systems

−Individual Water Systems

−Public Water Systems

−Reverse Osmosis Water Systems

−Water Purifier Units

7. Materials Preservatives

Preservative of pesticide 

formulations applied to 

growing crops or crops 

after harvest 

−Adhesives/Coatings/Caulks (with potential to contact food)

−Cleaning Products (kitchen food contact surfaces)

−Dispersions/Emulsions/Solutions/ Suspensions (with 

potential to contact food)

−Paper/Paperboard (with potential to contact food)

−Plastic/Rubber Products (cutting boards, counter tops) 

Arts & Crafts Materials, such as finger paints, crayons, colored chalk,

pencils

Construction Materials, such as adhesives/paints and coatings/caulks not in 

contact with food, wallboard, ceiling tiles, flooring, Heating/Ventilating/Air 

Conditioning (HVAC) system filters and other components, pipes (nonpotable), mastics, joint compounds, grouting, cements, concrete admixes

Disposable Diapers

Industrial Matrices, such as metal working cutting fluids (MWFs), metal 

cleaning fluids, inks/dyes, fuels/oils, 

dispersions/emulsions/solutions/suspensions, slurries/pastes/gels, fuel and oil 

storage tanks, recovery drilling muds/packer fluids, polymers, resins, rubber, 

fracturing fluids, injection, well squeeze, insulation, refuse containers, 

moulded articles
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Food Uses Nonfood Uses

Direct Food Uses Indirect Food Uses

Nonfood pesticide formulations, such as lawns, crack and crevice 

pesticides, rodenticides, and human and pet treatments (e.g., fleas, lice, 

scabies, pet collars)

Paper and Paperboard Nonfood Contact Materials

Plastic and Rubber Nonfood Contact Materials, such as barrier fabric, 

shower curtain, cable/wire insulation, non-food containers, moulded articles

Textiles, such as clothing, footwear, bedding, cloth diapers, fibers, cordage, 

tarps, tents, awnings, auxiliaries (sizing/finishing agents), leather/hides, 

feathers, felt, carpets and padding, canvas, drapes, filters, shower curtains, 

rayon, yarn, cloth, insulation, wall and floor covering

8. Industrial Processes and Water Systems

Not applicable −Pulp/Paper Mill Water Systems (food contact paper) −Air Conditioner/Refrigeration Condensate Water Systems

−Air Washer Water Systems

−Bilge Water

−Coal Slurry Systems

−Commercial/Industrial Cooling Water Systems[Recirculating/Once 

Through]

−Evaporative Condenser Water Systems

−Gas/Oil Equipment/Fluids

−HVAC Systems

−Industrial Processing Water/Fluid Systems

−Industrial Waste and Waste Water Systems

−Industrial Drainage Systems

−Influent Water Filtration Systems

−Industrial Scrubbing System

−Pulp/Paper/Textile Mill Water Systems (e.g., newspaper print, magazine 

print) 

−Reverse Osmosis Water System (Non potable water)

9. Antifoulant Paints and Coatings

Not applicable −Nets Used for Aquaculture −Ballast Water Treatments

−Aquatic Vessel Coatings

−Aquatic Structures/Equipment

−Crab/Lobster Pots

10. Wood Preservatives

Not applicable Packing, transporting, or holding containers for raw 

agricultural commodities made from treated wood as per 

21CFR178.3800

Above Ground, including trusses, millwork, siding and trim; furniture, 

decking, railings, flooring, fence pickets, and grape trellises, etc.

Ground Contact, including fence, deck and guardrail posts, crossties, 

permanent wood foundations, buildings poles, posts, utility poles, ties, 

freshwater piling, raised garden beds
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Food Uses Nonfood Uses

Direct Food Uses Indirect Food Uses

Marine Use, including piling, bulkheads, bracing 

11. Swimming Pools and Spas

Not applicable Not applicable −Spa and Hot Tub Water Systems

−Swimming Pool Water Systems

−Water Parks Water Systems

12. Aquatic Areas

Commercial Fishery 

Water Systems

Agricultural Drainage Systems

Intermittently Flooded Areas/Water (rice paddies, cranberry 

bogs)

−Lakes/Ponds/Reservoirs

−Ornamental Ponds/Aquaria

−Salt Water Sites

−Streams/Rivers/Channeled Water