Ch.6: Personal Protective Equipment

2. Barrier Effectiveness & the Comfort Tradeoff

• Barrier effectiveness generally increases with thickness; but comfort and dexterity decrease as thickness increases (thicker gloves are harder to work in).
• Don't compromise safety for comfort. Removing required PPE for heat/humidity is not an option — take frequent breaks and stay hydrated with water.
• To be effective, PPE must be:

1. Sufficiently protective (hands, body, face, feet, head, eyes)
2. Resistant to penetration of pesticide mixtures onto skin
3. Resistant to punctures or tears under normal use
4. Well sealed at seams
5. Comfortable enough that people wear it

3. Chemical Resistance

• Chemical resistant = made of a material that allows no measurable movement of the pesticide through it during use.
• No single material is resistant to all chemicals or in all situations — the label may list specific materials for a product/formulation.
• Effectiveness of PPE depends on: its design, construction, and thickness; whether it is used and maintained correctly; and how long it is used.
• Even chemical resistant PPE eventually lets pesticides through due to material degradation.
• Useful-life factors: contact time with the chemical, concentration, temperature, and the product itself.

4. Dermal (Skin) Protection

• Skin is a major protective organ but also a major route of entry — most PPE instructions aim to keep pesticides off the skin.
• Basic work clothing: long-sleeved shirt, long pants, socks, shoes.
• Good practices (not on labels): tightly woven fabric (no mesh), snug collar and cuffs, no holes or tears, close-toed shoes/boots (waterproof is a plus).

Coveralls

• An added layer worn over other clothing; tighter weave = better protection.
• Disposable coveralls can be worn several times if free of contamination.
• May NOT protect you from a concentrate splash/spill — if spills occur, remove and decontaminate the skin.

Gloves

• Most pesticide exposure occurs to the hands and forearms — gloves greatly reduce it.
• Wear the specific waterproof or chemical resistant type listed on the label.
• Listed chemical resistant materials are specified at ≥14 mils (butyl, nitrile, neoprene, natural rubber, polyvinyl chloride, Viton); barrier laminate and polyethylene are also listed.
• Arms raised and lowered? Cuff gloves to the outside of the sleeve with heavy-duty tape or an elastic band.
• Wash hands before putting gloves on if you've handled pesticides — otherwise you contaminate the inside.
• Wear gloves even when not required: handling/applying pesticides, handling/rinsing/disposing containers, repairing/washing equipment, washing PPE.

5. Ocular (Eye) & Face Protection

• Face/eye exposure is less frequent than hand contact but potentially more serious.
• Contact lenses: be extra cautious — they can absorb chemicals and hold them against the eyes.
• Safety glasses (with full side shields): best protection from flying objects, but only minimal protection from chemical dust/mist/splash; do not work over prescription glasses.
• Goggles: fit to form a seal around the eyes. Cup goggles cover the eyes completely; cover goggles fit over prescription eyeglasses.
  • Indirectly ventilated = splash resistant, minimize fogging, exclude direct passage of dusts/liquids/particles.
  • Directly ventilated = liquid/aerosol can enter through the perforations.
• Face shields: worn when splashes are likely (usually mixing/loading); headband must be nonabsorbent.

6. Footwear

• Some labels list only shoes plus socks; others require waterproof or chemical resistant footwear plus socks.
• Chem-resistant boots: often natural rubber (may be coated with polyurethane/PVC); heights 6 in. (ankle) to 16 in.+ (over-the-knee).
• Do NOT tuck pant legs into boots — it can funnel spills inside.
• Around dew, waterproof footwear or a rubber overshoe keeps out moisture that may carry pesticides washed off plants.

7. Respiratory Protection

• Respirator = a safety device that protects you from inhaling contaminated air.
• Wear one when: the label requires it; mixing/loading highly toxic concentrates; handling/applying in an enclosed area; or continuous inhalation exposure over an extended period.
• The label specifies the type and, if needed, the cartridge/canister/filter. A respirator that protects against one chemical won't necessarily protect against another.

Two basic types

• Particulates → a dust/mist respirator is fine (protects from dusts/droplets, not vapors).
• Organic vapor cartridge required → must use a vapor-removing respirator.
• NIOSH-approved = approved by the National Institute for Occupational Safety and Health. Nuisance dust masks and some surgical masks are NOT NIOSH-approved — inadequate.
• Styles: half-mask (mouth and nose) vs. full facepiece (also protects the eyes).

8. Fit Test vs. Seal Check (common exam point)

• Records for medical evaluations and Fit Tests: keep 2 years.
• Positive pressure Seal Check: cover the exhalation port and lightly exhale — escaping air = a gap.
• Negative pressure Seal Check: cover the intake and inhale — a good seal makes the mask collapse with no leakage.

9. Cleaning & Disposal

• Clean PPE after each use or at the end of each day. Follow the equipment manufacturer's instructions (if none for washables, use detergent and hot water). Keep and wash PPE separately from other laundry.

Washing fabric clothing

• Outdoors: shake off dust/granules (cuffs, pockets).
• Wash separately from family clothing (residues transfer).
• Wash only a few garments at a time (less = cleaner).
• Presoak or use the prewash cycle.
• Hot water, highest setting, heavy-duty liquid detergent. No bleach or ammonia (never mix the two).
• Drain the water — don't use the water-saving feature.
• Recheck for stain/odor; rewash, and if a second wash fails, discard.
• Line dry (avoids dryer contamination; sunlight degrades some residue).
• How easily laundering removes a pesticide depends on its FORMULATION, not its toxicity.

Other

• Highly contaminated PPE (large amounts, concentrate): dispose of it as waste (wearing gloves).
• Wash the outside of gloves and footwear BEFORE removing them, to keep pesticide off your hands.
• Test gloves for leaks by filling with water and squeezing — leaky gloves don't protect.
• Replace PPE regularly — pesticides eventually penetrate even resistant material.

Key Vocabulary