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Personal Protective Equipment (PPE) for Environmental Health Frequently Asked Questions

Below is information regarding specific questions about personal protective gear and various health hazards. Click on the down arrows to expand the answer.

When conducting investigations where there is a lot of dust and debris, such as in home renovations, construction sites, and disaster cleanup sites, use of dust masks or surgical-type masks may provide adequate protection. If the hazard assessment involves potential lead or asbestos contamination, if there is fecal material from birds or bats present, or if mold spores are a potential hazard, an N95 respirator is necessary to provide protection. When the investigation involves hazardous chemicals, gasses and/or vapors, the EH practitioner should not enter the site until it has been cleared by a hazardous materials team, unless the EH practitioner is specifically trained in these types of investigations. In most situations, the respiratory equipment required is beyond the scope of most local health departments. Confined spaces and other oxygen-deficient environments require the use of self-contained breathing apparatus, and should only be entered by professionals. If the site is an asbestos or lead abatement project, the site should only be entered by a certified person. Lead and asbestos inspections require the use of a half-mask respirator with replacement P100 filters specifically designed for either lead or asbestos (CFR 1910.1025, Lead, and CFR 1910.1001, Asbestos).

Most farm odor problems involve the release of gases, so use of an N95 particulate respirator will not protect you from any gases present. An N95 respirator may be helpful if the farm is extremely dusty, especially if the dusts are from agricultural products that may cause allergic reactions (hay, grains, feed). Care must be exercised to keep from entering an area with unsafe levels of gases, and you should try to remain in well-ventilated areas during the investigation. Other PPE that should be worn include boots/shoes with shoe covers; Tyvek® suit to protect from manure and/or agricultural chemicals; and eye protection (if very dusty).

Before entering, be sure that the house is structurally sound enough to allow safe entry. Contact a building inspector and the building owner to be sure entry can be done safely. An N95 respirator is probably appropriate, as lead dust and asbestos fibers may be present. Additional PPE would include a Tyvek® suit, shoe covers, nitrile gloves, and a hardhat. If you determine that lead paint or asbestos is present, refer the situation to the Wisconsin Department of Health Services (DHS) Asbestos and Lead Section or to a local lead/asbestos risk assessor.

After a disaster, the first step is to assure that the structure is sound. Contact a building inspector if there is a question. In addition, check with Emergency Management officials to be sure the utilities have been disconnected and that you have authorization to be in the home. After being cleared to enter, you should wear a Tyvek® suit with shoe covers, nitrile or disposable gloves, eye protection, and workboots or rubber boots.  Post-disaster sites often contain debris, sharp objects, and chemical residues, so be careful not to get scratched or injured. If mold is obvious or musty odors are present, an N95 respirator should also be worn to protect against mold spores.

Before entering, be sure that the local fire department’s Hazardous Materials (Haz Mat) team or a hazardous waste contractor has cleared the site.  Meth labs often have residues of hazardous and toxic materials, so you must be certain that chemical fumes have been reduced to below safety standards. Contact the Haz Mat team or contractor to determine if additional air monitoring is necessary. In addition, check with the law enforcement agency in charge to be sure that all evidence needed by the law enforcement agency has been collected and that law enforcement has authorized your entry into the meth lab. Wear a Tyvek® suit with shoe covers, nitrile or disposable gloves, and eye protection. Use of a dust mask, surgical-type mask, or N95 respirator will not be helpful in protecting you from chemical fumes and will not be necessary, unless particulate hazards (dust, mold, insulation, etc.) are a possibility. 

Yes, if you have been trained in the use of the Lumex Mercury Analyzer®, you can investigate as long as the air concentration stays below the Permissible Exposure Limit (PEL) that does not require a respirator. If the air quality is unknown or if the mercury vapor level exceeds standards, a half-face respirator with a mercury vapor chemical cartridge is necessary (CFR 1910.134(d)(3)). N95 or P100 respirators do not provide adequate protection from mercury vapors. Use a Tyvek® suit, shoe covers, and nitrile gloves for PPE. Consult with Division of Public Health Environmental Health staff prior to beginning the investigation.

In a hoarding situation, especially with large amounts of fecal material present, wear a Tyvek® suit, disposable gloves, eye protection, and shoe covers.  If the house is dusty or mold may be present, use an N95 respirator. If the house strongly smells of ammonia/urine, especially if the odor begins to irritate your eyes and mucous membranes, you should leave the house and obtain equipment or personnel to sample the ammonia concentration. Ventilation prior to entry is preferable, as ammonia will lead to desensitized olfactory detection over time.

Last revised September 2, 2020