Vegetable pesticide series: Does it require a respirator?

A 2018 Worker Protection Standard respirator requirement guide for vegetable growers.

The Worker Protection Standard and respirators

The Worker Protection Standard (WPS) is a regulation designed to protect farmworkers from dangerous exposure to pesticides. A recent update in 2015 has aligned the WPS with most of the Occupational Safety and Health Administration (OSHA) provisions for using respirators.

The revised WPS includes specific requirements for using respirators when using pesticide products under the Agricultural Use Requirements that requires the use of a respirator. This revision requires all those who mix, load and apply pesticides, including self-employed handlers, to have a medical evaluation and annual fit-tests for each type of respirator required by the pesticide product label and annual training regarding the proper use of each respirator to be used by the handler.

Remember, the WPS does not apply when the pesticide is used in a manner not directly related to the production of agricultural plants and post-harvest treatments of the harvested portions of an agricultural plant under the Agricultural Use Requirements on the pesticide label. When using a pesticide for uses other than those covered in the Agricultural Use Requirements section of the label, the worker exposure is subject to the requirements of the OSHA Hazard Communication Standard, and either MIOSHA Part 700 or Part 451, including the need for respiratory protection. The Safety Data Sheet for a pesticide would indicate if you need a respirator for non-agricultural uses.

For a complete primer on the updated WPS, see the “How to Comply with the 2015 Revised Worker Protection Standard” manual.

Respirator label language

To find whether your pesticide requires a respirator to mix, load or apply, see the Personal Protective Equipment (PPE) requirements listed in the Precautionary Statements section of the label in the ”Hazards to Humans (and Domestic Animals)” subsection.

The product formulation, toxicity and type of application influence the type of respirator needed. Manufacturers use criteria approved by the Environmental Protection Agency (EPA) to assign PPE respirator requirements on labels. The respirator precaution statement can be very general, but some product statements can also be quite specific, with different instructions for mixers, loaders, applicators and application type. Some may include details on half-mask or full-mask, and some may feature exemptions when using engineered controls, such as closed or mechanical transfer mixing/loading systems, water-soluble packaging or enclosed sprayer cabs.

Others may list multiple respirator options with National Institute of Occupational Safety and Health (NIOSH) respirator classes and filter series. Labels can be confusing because respirator terminology was changed by NIOSH. In 1995, NIOSH took over full responsibility for respirator certifications from the Mine Safety and Health Administration (MSHA). Some pesticide labels continue to use the old MSHA terms.

What is a respirator?

A respirator is a personal protective device that is worn on the face, covers at least the nose and mouth, and is used to reduce the wearer’s risk of inhaling hazardous airborne particles (including dust particles and infectious agents), gases or vapors. The many types of respirators available include (1) particulate respirators, which filter out airborne particles; (2) “gas masks,” which filter out chemicals and gases; (3) airline respirators, which use compressed air from a remote source; and (4) self-contained breathing apparatus, which include their own air supply. Often, a Grade D air cylinder or an air compressor supplies the breathable air.

The category of particulate respirator can be further divided into (1) disposable or filtering facepiece respirators, where the entire respirator is discarded when it becomes unsuitable for further use due to excessive resistance, sorbent exhaustion or physical damage; (2) reusable or elastomeric respirators, where the facepiece is cleaned and reused but the filter cartridges are discarded and replaced when they become unsuitable for further use; and (3) powered air purifying respirators (PAPRs), where a battery-powered blower moves the air flow through the filters.

Filter series

When the ambient air contains particulates (e.g., dusts, mists), air-purifying respirators use filters that are classified on the basis of oil degradation resistance and filter efficiency. To describe oil degradation resistance, NIOSH classifies a filter as N (not oil resistant), R (oil resistant) or P (oil proof). Among the N, R and P series classes, there are also three filter trapping efficiency levels: 95, 99 and 100.

A filter classified as High Efficiency (HE) can only be used on powered air-purifying respirators. Respirators that have particulate filters will not protect you against gases, vapors and the non-particulate components of fumes, mists, fogs, smoke and sprays.

Cartridges and canisters

The terms “cartridges” and “canisters” are used interchangeably in air purifying respirators. They are both containers with a filter, sorbent or catalyst, or a combination of these items designed to remove specific contaminants from the air passed through the container. Often, a cartridge is the term for a half- or full-face respirator and a canister is the term used for a gas mask. Essentially, the terms are interchangeable.

Select the appropriate cartridge or canister for the contaminant in question. For example, a cartridge or canister specifically designed to remove organic vapors will not remove an acid gas or a particulate, a particulate cartridge will not remove organic vapors, and a cartridge or canister designed specifically for ammonia will not remove an organic vapor.

Cartridges and canisters are color-coded to help you select the appropriate one. You can find the color-coding requirements of labels for canisters and cartridges online through OSHA's General Respiratory Protection Guidance for Employers and Workers. You may require more than one cartridge to protect against multiple hazards; for example, you may need a chemical cartridge and a particulate filter in combination.

NIOSH TC codes

What do NIOSH codes mean? A NIOSH TC-number is assigned to respirator masks and cartridges after they are reviewed and approved by NIOSH. There may be a filter series identifier (e.g., N95) as well. NIOSH approval numbers are for the entire respirator unit—you will void the approval if you use one manufacturer’s mask and another manufacturer’s cartridge or canister. You should use only NIOSH-approved respirators.

The categories are as follows.

Air purifying respirators

TC-84A: Non-powered dust/mist respirators with particulate filter or combination chemical cartridge with particulate filter are one the two most common styles of respirator required on pesticide labels. They are often a disposable facemask with or without a N, R or P designation, but may be a full or half-face mask with a N, R or P designated particulate-removing filter, AND/OR combination chemical cartridge or canister with an N filter.

TC-23C: Non-powered respirators with chemical cartridge or powered air-purifying respirators with chemical cartridge OR a particulate filter were one of the two most common styles of respirator required on pesticide labels. Older pesticide labels sometimes require an MSHA TC-23C respirator with both a chemical cartridge AND a particulate pre-filter. However, currently only TC-84A respirators are tested with combinations of filters and cartridges. So, in these special cases where labels have not yet gone through the re-registration process, growers will actually be expected to use a TC-84A combination respirator, and not the TC-23C listed.

TC-21C: Powered dust/mist particulate respirators (no chemical cartridge combination). These are half-face or full-face masks, hoods or helmets with a battery-powered fan that moves air through the filters and circulates it through the mask. High Efficiency filters selected for the contaminants must be used with these types of respirators. These feature interchangeable cartridges for different particulate filter series and a pre-filter.

TC-14G: Gas masks with canisters are sometimes listed as an option for certain soil fumigants. They are similar to full-face TC-23C respirators, but are designed specifically for chemical gas or biological exposure. These feature interchangeable cartridges for different particulate filter series.

Atmosphere-supplying respirators

TC-13F: Self-contained breathing apparatus (SCBA) is an atmosphere-supplying respirator; the respirator face piece is connected to portable breathable air in cylinders carried on the back of the wearer.

TC-19C: Supplied-air respirators (SAR) are an atmosphere-supplying respirator; the respirator face piece is connected to a “fixed” air source (not designed to be carried by the wearer).

Vegetable pesticides that require respirators

So, what commonly used pesticides labeled for vegetable use have respirator label language? Below is a list in order by trade name. The chemicals on this list that do not require a respirator for agricultural production under WPS may still require a respirator for non-agricultural uses under OSHA’s Hazard Communication Standard, MIOSHA Part 700 or Part 451.

To find out if a non-agricultural use requires a respirator, look at the Safety Data Sheet. If the label did not require a respirator for agricultural use, we indicated “no.” If the label required any type of respirator for any or all processes, we indicated “yes, see label.” Always double-check the label and Safety Data Sheet that comes with your specific product and formulation.

Download printable version of this table.

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