: PERSONAL: PROTECTIVE ' EQUIPMENT GUIDE CHOOSING CHEMICAL- RESISTANT PPE ------- jany pesticide labels instruct the user to Iwear personal protective equipment (PPE) — clothing and devices that protect the body from contact with pesticides or pesticide residues. Some labels require the use of chemical-resistant PPE — items that the pesticide cannot pass through during the time it takes to complete the task. The labels of a few pesticides, .such as some fumigants, prohibit the use of chemical-resistant PPE. Most chemical-resistant PPE items are plastic or rubber. But not all these materials are equally resistant to all pesticides and under all conditions. •**. Chemical Resistance Three factors affect a material's chemical resistance: the exposure time, the exposure situation, and the chemical properties of the pesticide product to which the material is exposed. Exposure time Not all types of materials that are resis- tant to a particulajtpesticide.will,prpyide ,.„ „; protection for the'same amount of time. Some will keep therpesticlde. out.for a long timei" ~""it Others will allow the pesticide to reach the skin fairly quickly. Disposable plastic gloves, rshoe covers, or aprons may provide enough^-'-^-f protection for tasks that can Be done in a few~^ minutes. Longer jobs usually require items made of a more resistant material. A pesticide begins to move into a material as soon as it gets on the surface. The pesticide continues to move into and through the material until the pesticide is removed. Help prevent pesticides from getting through chemical-resistant items, such as gloves, boots, and aprons, by regularly rinsing off pesticides that are splashed or spilled on -them. — Any plastic or rubber material is resistant to dry pesticides and to .water- based pesticides (those that use water as the only diluent or solvent). Dry pesticides include dusts, granules, pellets, and some baits. Water-based pesti- cides include wettable powders, soluble powders, some solutions, dry flowables (water- dispersible granules), and microencapsulated pesticides. Chemical resistance to non-wafer- based liquid pesticides depends on the type of solvent in the formulation. Liquid pesticides, that are not water-based may be emulsifiable concentrates, ultra-low- volume and low-volume concentrates, low- concentrate solutions, flowablesj aerosols, and invert emulsions. Common solvents are xylene, fuel oil, petroleum distillates, and alcohol. If the label does not indicate the types of materials that are chemical-resistant to the pesticide product, select sturdy barrier- laminate, butyl, or nitrile materials. Then watch for _signs that the material is not "chemical-resistant. "•-•' -Sometimes it is easy to see when a plastic or rubber is not resistant to a pesticide. The ..material may: ; . B change color, H become soft or spongy, S swell or bubble, 13 dissolve or become jelly-like, H crack or get holes, H become stiff or brittle. *'!_ If any of these changes occur, discard the item and choose another type of material. ------- Chemical resistance is often stated in terms of exposure time. For example, neo- prene may be resistant to one solvent for 30 minutes or less and to another solvent for more than 4 hours. Exposure situation A chemical-resistant material will not continue to be protective if it is damaged. For tasks that involve handling sharp objects or walking through rough terrain, a sturdy material would be necessary to resist punc- tures or tears. Type'of chemical No single material can protect against all a" material depends" on whether the pesticide is liquid or dry, and what diluents or solvents are used. Choosing Chemical- Resistant Materials The pesticide label may state what materi- als are chemical-resistant to the pesticide product. If it does not, look for another source of help' in making a selection7The Environ- ~ mental Protection Agency, the United States Department of Agriculture - Cooperative Extension Service, pesticide producers, or PPE dealers may offer guidance. Unless the pesticide.label directs other- wise, do not use items that are made of— or lined with — absorbent materials such as cotton, leather, and canvas. These materials are not chemical resistant, and they are difficult or impossible to clean after a pesticide gets on them. Even dry formulations can move quickly through woven materials and may remain in the fibers after several launderings. Gloves and footwear made of polyvinyl chloride (PVC) or rubber (butyl, nitrile, neoprene or natural rubber) must be at least 14 mils thick. Pesticides can leak through stitching1 holes and. gaps.in.seams,,,For,_chemical ,,. resistance,:'choose^FE with sealed seamsT materials good choice for many situations. Barrier-lami- nate (Silver Shield®/ 4-H®) gloves may be uncomfortable and clumsy to wear for some kinds of tasks. Try wearing fitted rubber gloves over barrier-laminate gloves for comfort, protection and dexterity. ------- |