5.3 Worker Protection Standard (WPS)

What the WPS Is and Why It Exists

Quick Answer: The Worker Protection Standard for Agricultural Pesticides (WPS) is the federal rule, codified at 40 CFR Part 170, that protects employees who handle pesticides or work in treated areas on agricultural establishments. It is the only federal occupational standard aimed specifically at pesticide exposure in agriculture, and it applies in Michigan through both EPA enforcement and MDARD under Part 83.

The WPS exists because agricultural workers and pesticide handlers historically absorbed far more pesticide than the general public. Before the rule, workers re-entered treated fields without warning, handlers mixed concentrated product without training, and decontamination supplies were rare. The WPS closes those gaps by placing duties on the agricultural establishment (the employer of the workers and handlers).

Who and Where the WPS Applies

The WPS applies to agricultural establishments — defined as farms, forests, nurseries, and greenhouses — when WPS-labeled pesticides are used. A WPS-labeled product carries an Agricultural Use Requirements box on the label; only those products trigger the full WPS. Products labeled solely for non-agricultural uses (structural, right-of-way, residential) do not invoke the WPS even though other safety rules still apply.

The WPS protects two populations:

• Pesticide handlers — those who mix, load, apply, flag, clean equipment, or handle opened containers of WPS-labeled product.
• Agricultural workers — those who perform tasks related to the production of plants (hand labor, irrigation, scouting) in areas that have been treated or that are under an REI.

Immediate family members of the establishment owner are exempt from many WPS provisions when working on their own family farm, but handlers working for hire on that farm are still fully covered.

The Core WPS Requirements

The 2015 revisions (effective January 2017) reorganized the WPS into a set of specific, enforceable duties. The core exam and Michigan's commercial applicator exam both test these.

1. Pesticide safety training

Handlers and workers must receive pesticide safety training before they begin a WPS-covered task. Training must be repeated at least every 12 months. The trainer must be a certified applicator or have completed an EPA-approved train-the-trainer program. Training content must cover, at minimum: signs and symptoms of poisoning, emergency response, label and SDS use, hazards, routes of exposure, PPE, REIs, and decontamination.

2. Central posting and notification

The establishment must post, at a location accessible to workers (and from the start of the work day):

• An application list (or display) showing each WPS-labeled application — product, active ingredient, EPA registration number, location, date and time application started and ended, and REI.
• Safety Data Sheets (SDS) for each WPS-labeled product used.
• The EPA Pesticide Safety Poster with safety information, the nearest emergency medical facility, and a reminder to wash hands before eating or drinking and to remove work boots at the end of the shift.

Application information must remain posted for 30 days after the REI expires, and SDS for 30 days after the product is no longer used on the establishment.

3. Restricted-Entry Intervals (REI)

An REI is the period after a pesticide application during which entry to the treated area is prohibited for anyone other than an appropriately trained and equipped handler. The REI appears in the Agricultural Use Requirements box of the label. Under 40 CFR 156.208 the label REI is driven by the most toxic active ingredient in the product: 48 hours if any active ingredient is in Toxicity Category I, 24 hours for Category II, and 12 hours for everything else. Labels can and do extend those minimums for specific crops, activities, or arid regions.

There is a persistent myth of a "4-hour default REI." There is no such thing on a WPS-labeled product — 12 hours is the floor. If a question offers a shorter interval for a WPS product, it is a distractor.

4. Early entry

Early entry during an active REI is allowed only for three narrow exceptions:

• No contact — tasks with no contact with anything treated, including soil, water, surfaces, and plants. No time limit and no early-entry PPE requirement, precisely because there is no contact.
• Short-term — tasks involving contact with treated surfaces for no more than 1 hour in any 24-hour period; the label's early-entry PPE is required.
• Agricultural emergency — an unforeseen circumstance the employer could not have anticipated that would cause substantial economic loss; declared under the rule's conditions, with early-entry PPE required.

Early-entry workers must be at least 18, must have received the required training and instructions, and must be supplied the label-specified early-entry PPE at no cost.

5. Application Exclusion Zones (AEZ)

The Application Exclusion Zone is the area around the application equipment that must stay clear of unprotected people during an outdoor application. It moves with the equipment, exists only while the application is happening, and extends horizontally in all directions — not just downwind. It can reach beyond the establishment boundary, onto a road, a neighboring yard, or a school playground.

Handlers must suspend the application if anyone other than an appropriately trained and equipped handler enters the AEZ, whether or not that person is on the establishment. A narrow exemption lets an owner and the owner's immediate family shelter inside a closed building; that exemption does not extend to employees or to anyone else.

6. Personal protective equipment

Handlers must be provided, at no cost to the handler, the label-specified PPE for each task. The establishment must ensure PPE is inspected before each use, cleaned, repaired, and replaced; provide a pesticide-free area for handlers to put on and take off PPE; and ensure handlers do not take contaminated PPE home.

7. Decontamination supplies

The establishment must provide decontamination supplies within 1/4 mile of handlers and workers (or at the nearest point of vehicular access):

• Enough water for routine and emergency whole-body washing and eye flushing (at least 1 gallon per worker and 3 gallons per handler).
• Soap and single-use towels.
• A clean change of coveralls for handlers.

Decontamination supplies must be available to handlers throughout the handling task, and to workers during the work period and for 30 days after the REI expires for anyone entering a treated area. Water for eyeflushing must be immediately available to handlers using a product whose label requires protective eyewear.

8. Emergency assistance

If a handler or worker is taken to a medical facility because of a pesticide exposure, the establishment must provide, within 24 hours: the product name, EPA registration number, and active ingredient; the SDS; a description of how the product was used; and the circumstances of exposure. The establishment must also arrange transportation to a medical facility.

9. Hazard communication and information exchange

Before any application, the handler must inform the establishment of the product, active ingredient, EPA registration number, location, and dates of application. The establishment then uses that information to update the central posting. This two-way exchange keeps everyone in the chain aware.

Michigan's Application of the WPS

In Michigan, the WPS is enforced jointly by EPA Region 5 and MDARD. Michigan's Part 83 of NREPA references the federal standard, and MDARD's pesticide inspectors conduct WPS inspections during routine applicator audits. Michigan applicators should:

• Treat the WPS as the floor and add Part 83 requirements where they are stricter (record-keeping, school IPM notification, RUP designation).
• Maintain records of WPS training for at least two years (federal minimum), separately from the Regulation 636 application records, which run 3 years for restricted-use and 1 year for general-use applications.
• Coordinate with growers so the application list and SDS are accessible during the REI.
• Use MDARD's compliance assistance materials (canr.msu.edu/psep and Michigan.gov/pesticide) when designing a WPS-compliant safety program.

Exam Scenario

A common exam question asks what to do when a worker wants to re-enter a field that is under an REI. The correct answer is to deny entry unless an early-entry exception applies, and even then only with the label's early-entry PPE. Another asks where decontamination supplies must be located — within 1/4 mile of workers and handlers, or at the nearest point of vehicular access. A third tests AEZ distance: 100 feet in all directions for aerial, air blast, fumigant, mist, fog, and fine sprays, 25 feet for ground sprays above 12 inches with medium or larger droplets, and no AEZ otherwise. "Downwind only" and "stops at the property line" are both wrong.