3.3 Worker Protection Standard (WPS)

What the WPS Covers

The Worker Protection Standard (WPS), codified at 40 CFR Part 170, is the federal regulation designed to reduce pesticide-related illness and injury among agricultural workers and pesticide handlers. It applies to agricultural establishments - farms, forests, nurseries, and greenhouses - where pesticides are used in the production of agricultural plants. Iowa commercial applicators who treat these sites must comply with WPS in addition to IDALS pesticide rules.

Who Is Protected

• Workers - anyone employed to do tasks such as harvesting, weeding, watering, or scouting in areas that have been treated with WPS-labeled pesticides or that are under a restricted-entry interval (REI).
• Handlers - anyone who mixes, loads, transfers, applies, or cleans pesticide equipment, or who handles opened containers.

Core WPS Responsibilities of the Agricultural Employer

The WPS places duties on the agricultural employer (the owner or operator of the establishment). Commercial applicators who are hired to treat a site should coordinate with the employer so these duties are met.

1. Pesticide safety training - workers and handlers must receive WPS training before beginning work in treated areas, with annual refresher training.
2. Notification - workers must be warned about treated areas through posted warning signs, oral warning, or both, depending on the REI.
3. Restricted-entry interval (REI) compliance - keep workers out of the treated area until the REI on the label has expired and warning signs are removed or covered.
4. PPE for early entry - if early entry is permitted under an exception, provide and maintain the PPE the label requires for early-entry tasks.
5. Decontamination sites - provide water, soap, and towels for washing, and for handlers a clean change of clothing.
6. Emergency assistance - if a worker or handler is poisoned or injured, provide transportation to a medical facility and give the medical provider the label and safety data sheet (SDS).
7. Display of application information - post the pesticide application list, SDS, and safety poster at a central location.

Restricted-Entry Interval (REI)

The REI is the time after the end of a pesticide application during which entry into the treated area is restricted. The REI is printed on the product label and is typically 4, 12, 24, 48, or 72 hours, depending on toxicity.

When two or more pesticides are applied together, the longest applicable REI governs. Warning signs must remain during the REI and be removed or covered when it expires.

Early-Entry Exceptions

Entry during the REI is allowed only under specific exceptions in 40 CFR 170.603:

• No contact - tasks with no contact with treated surfaces.
• Short-term tasks - up to 1 hour in any 24-hour period, with label-specified PPE.
• Emergency - dealing with an agricultural emergency declared by EPA.
• Limited-contact and irrigation tasks - narrowly defined tasks with strict hour limits and PPE.

Even when an exception applies, the employer must provide the PPE the label requires for early entry and decontamination supplies at the work site.

Application Exclusion Zone (AEZ)

The 2015 WPS revisions created the Application Exclusion Zone (AEZ) - the area surrounding pesticide application equipment that must be free of all persons other than appropriately trained and equipped handlers during outdoor applications. The AEZ exists only during the application, moves with the equipment, and can extend beyond the boundaries of the establishment.

Two duties apply. The agricultural employer must not allow or direct any worker or other person to enter or remain in the AEZ within the establishment. The handler performing the application must immediately suspend the application if any person (other than a trained handler involved in the application) is in the AEZ, whether on or off the establishment; the application may resume once those individuals have left the AEZ. A 2024 EPA rule restored the off-establishment AEZ protections and the 100-foot/25-foot distance criteria.

Decontamination Sites

The WPS sets minimum decontamination supplies:

• For workers: at least 1 gallon of water per worker at the start of each work period, plus soap and single-use towels, located together outside the treated area and within a quarter mile of where workers are working.
• For handlers: at least 3 gallons of water per handler, soap, single-use towels, and one clean change of clothing. When mixing products that require protective eyewear, the site must also provide an eye-flush system delivering at least 0.4 gallons per minute for 15 minutes, or at least 6 gallons of water in suitable containers.

Hand-sanitizing gels do not count as soap, and wet towelettes do not count as single-use towels. Water quality and temperature must not cause illness or injury if it contacts skin or eyes or is swallowed.

How WPS Interacts with Iowa Rules

IDALS enforces both Iowa pesticide rules (Iowa Administrative Code Chapter 21-45) and the federal WPS where it applies. A commercial applicator treating an Iowa farm, nursery, or greenhouse must:

• Follow the label REI and posting requirements,
• Coordinate with the agricultural employer so workers receive notification and training,
• Keep application records that include the product, EPA registration number, rate, date, and REI,
• Provide emergency assistance information if an incident occurs.

WPS does not apply to lawn care, structural pest control, or right-of-way treatment that is not on an agricultural establishment. For those sites, the label and Iowa rules still govern PPE and re-entry.