4.3 Personal Protective Equipment (PPE), Respiratory Protection & Maintenance

Personal Protective Equipment (PPE), Respiratory Protection & Maintenance

The Statutory Mandate of PPE Under FIFRA & WPS

Under FIFRA Section 12(a)(2)(G) and the federal Worker Protection Standard (WPS, 40 CFR Part 170), the personal protective equipment (PPE) specified on the pesticide label is the absolute statutory minimum legal requirement. Failing to wear every listed item while handling, mixing, loading, applying, or decontaminating pesticide equipment is a federal and state violation.

The "Minimum Legal Standard" Principle

1. You May Never Wear Less PPE Than the Label Requires: Omitting any label-mandated PPE constitutes unlawful pesticide misuse, exposing applicators to civil penalties and license revocation.
2. You May Legally Wear MORE PPE Than the Label Requires: The label establishes the protective baseline. An applicator handling a product requiring only long sleeves and chemical-resistant gloves may legally add a chemical-resistant apron, face shield, and P100 respirator during high-risk operations such as pouring concentrates or hopper loading.

Under WPS, agricultural employers must provide clean, operable PPE, ensure correct fitting and usage, provide clean storage isolated from chemical vapors, and prohibit employees from taking contaminated PPE home.

Chemical-Resistant Polymer Materials vs. Prohibited Fabrics

A material is chemical-resistant only if it prevents measurable movement of chemical active ingredients and solvents through to the skin during the operational period.

• Permeation: The molecular diffusion of a chemical through a protective material without causing visible physical changes.
• Degradation: The physical breakdown of a material caused by chemical contact, characterized by softening, blistering, cracking, swelling, or embrittlement.
• Penetration: Chemical movement through closures, seams, pinholes, tears, or porous weaves.

Approved Polymer Materials

Applicators match glove and suit materials to formulation solvents using EPA Chemical Resistance Categories (A through H):

• Nitrile Rubber: Copolymer of acrylonitrile and butadiene. Provides excellent resistance to petroleum hydrocarbon solvents, emulsifiable concentrates (EC), organic acids, oils, and greases. The standard agricultural glove material, offering high puncture resistance.
• Butyl Rubber: Synthetic copolymer offering superior protection against toxic gases, hazardous esters, ketones, and concentrated acids.
• Neoprene: Synthetic chloroprene rubber offering broad resistance against acids, caustics, alcohols, and fertilizers.
• Barrier Laminate (e.g., 4H® / Silver Shield®): Multi-layer polyethylene laminate providing universal chemical resistance across all EPA solvent classes. Relatively stiff with lower dexterity; frequently worn with outer nitrile gloves.
• Viton®: Fluoroelastomer providing premium resistance to chlorinated and aromatic hydrocarbon solvents; highly specialized.

Strictly Prohibited Materials

• Leather (Boots, Gloves, Belts): Porous organic material that rapidly absorbs pesticide concentrates through capillary action. Leather can NEVER be decontaminated. Trapped chemicals form a permanent toxic reservoir, continuously leaching through skin with every wear. Contaminated leather must be disposed of as hazardous waste.
• Cotton, Canvas, and Denim: Porous textiles that absorb liquids instantly, holding chemical solutions in prolonged direct contact with skin.
• Flock-Lined Gloves: Gloves lined with internal cotton or rayon flocking are strictly prohibited. Absorbed chemicals become trapped in the lining against warm, sweating hands, drastically accelerating dermal uptake. Handlers must use unlined chemical-resistant gloves (minimum 14 mil).

Anatomical PPE Engineering & Operational Handling Rules

• Chemical-Resistant Gloves (Minimum 14 mil, Unlined):
  • Spraying Downward (Ground Booms, Turf, Backpacks): Wear sleeves OVER / OUTSIDE the glove cuffs. Dripping chemical runs down the sleeve onto the ground, not into the glove.
  • Spraying Upward (Orchards, Overhead Canopies): Tuck sleeves INSIDE the glove cuffs, turning glove cuffs outward to catch descending drips.
  • Decontamination Protocol: Wash gloves thoroughly with soap and water BEFORE removing them to prevent transferring chemical residues onto bare hands.
• Eye and Face Protection: Standard safety glasses and directly vented goggles fail to block chemical splashes. Applicators must wear indirectly vented goggles equipped with baffled air ports that allow ventilation while blocking liquid entry, or non-vented goggles. A full-face shield covering brow to below the chin must be worn in addition to goggles during hazardous mixing, pouring, and hopper loading.
• Body and Foot Protection: A chemical-resistant apron made of butyl, neoprene, or nitrile covering chest to knees is mandatory during mixing and loading. Footwear must be unlined rubber or polymeric boots covering the ankles; pant legs must ALWAYS be worn OUTSIDE the boots so liquids shed onto the ground rather than inside the boot tops.

Respiratory Protection Under NIOSH and OSHA Standards

Under WPS (40 CFR Part 170) and OSHA (29 CFR 1910.134), label-mandated respirators require a comprehensive respiratory program. All agricultural respirators must be certified by the National Institute for Occupational Safety and Health (NIOSH) under 42 CFR Part 84.

Classifications of Respirators

• Air-Purifying Respirators (APRs): Remove contaminants by passing ambient air through mechanical filters or chemical sorbent beds. APRs do NOT supply oxygen and cannot be used in oxygen-deficient atmospheres (< 19.5% $O_2$).
• Atmosphere-Supplying Respirators (SCBA & Airline Respirators): Provide independent Grade D breathing air. Mandated for structural/grain fumigation (phosphine) and oxygen-deficient spaces.

NIOSH Particulate Filter Classifications

Particulate filters are categorized by oil resistance and filtration efficiency:

• N-Series (Not Resistant to Oil): Strictly for atmospheres with zero oil droplets (N95, N99, N100). Approved for dry formulations (WPs, dusts) and water-only sprays.
• R-Series (Resistant to Oil): Resistant to petroleum solvents and oil adjuvants (R95, R99, R100), but strictly limited to an 8-hour service life in oily atmospheres.
• P-Series (Oil-Proof): Oil-proof (P95, P99, P100 HEPA). Approved for all formulations, including heavy petroleum solvents (ECs) and oil adjuvants (COCs), with extended service life.
• Efficiencies: 95% (traps ≥ 95% of airborne particles ≥ 0.3 microns), 99% (≥ 99%), and 100 / HEPA (≥ 99.97%).

Chemical Cartridges & Organic Vapor Protection

Volatile solvent vapors pass freely through particulate filters. Handlers must use an Organic Vapor (OV) cartridge containing an activated carbon bed to adsorb solvent molecules. The agricultural standard is a combination OV/P100 cartridge, capturing volatile solvent vapors and atomized spray mists simultaneously. Cartridges must be replaced upon breakthrough odor/taste, End-of-Service-Life Indicator (ESLI) activation, at the end of the 8-hour workday, or per mandatory change schedules.

Medical Clearance, Fit Testing, and Daily Seal Checks

• Medical Evaluation: Mandatory OSHA medical questionnaire and physician evaluation prior to fit testing, ensuring cardiovascular and respiratory capability.
• Annual Fit Testing: Mandatory annually to confirm facepiece seal.
  • Qualitative Fit Test (QLFT): Pass/fail test using sensory agents (saccharin, Bitrex, irritant smoke).
  • Quantitative Fit Test (QNFT): Instrument-based measurement (PortaCount) calculating a numerical Fit Factor.
  • Facial Hair Ban: No facial hair (beards, stubble) may cross the respirator sealing edge. Facial hair destroys the airtight seal.
• User Seal Checks (Every Donning):
  • Positive Pressure Check: Cover exhalation valve, exhale gently; mask should bulge slightly with no air escaping.
  • Negative Pressure Check: Cover inhalation inlets/cartridges, inhale gently; mask should collapse inward and hold for 10 seconds without leaking.

PPE Maintenance, Laundering & Storage

• Daily Inspection: Inspect facepieces, valves, and straps for cracks, tears, brittle rubber, and missing diaphragms.
• Laundering Contaminated Work Clothing: Handle with gloves; wash completely separately from family laundry; pre-rinse garments; wash in hot water (≥ 140°F) on highest water setting with small load using heavy-duty liquid detergent (surfactants dissolve oily formulations); run an empty hot cycle with detergent afterward to clean the tub; line dry outdoors in sunlight (solar UV photolysis breaks down residues; never use a clothes dryer).
• Respirator Cleaning & Storage: Disassemble facepiece, wash in warm soapy water, rinse, air dry. Store clean, dry respirators in a clean, sealed airtight plastic bag (Ziploc) in a cool, clean locker. NEVER store PPE in pesticide storage buildings or near chemical containers, as activated carbon cartridges and rubber seals continuously adsorb ambient vapors, rendering them saturated and useless.