The investigation and assessment of human health hazards and nuisances that may be done by public health workers and Environmental Health (EH) practitioners will sometimes require the use of Personal Protective Equipment (PPE) to protect against potential exposures to environmental health hazards. While not all local health departments conduct environmental health hazard investigations, all public health workers and EH practitioners should be aware of the PPE requirements for these possible exposures, because ultimately, the local health officer is responsible for human health hazard abatement in his or her jurisdiction (DHS 140.04) as well as assuring the National Public Health Essential Services are implemented as described in Wisconsin Statute 250.03(10)(L).All PPE used by EH and public health workers should be in accordance with the agency’s PPE Program (OSHA Standard 29 CFR 1910.32). Elements of the PPE Program include hazard assessment, appropriate PPE selection and assuring its use, training, and monitoring of the program to ensure its ongoing effectiveness. (See PPE Program development page.) During human health hazard and environmental hazard investigations, a hazard assessment should also be done by conducting a walk-through survey of the areas in question. The purpose is to identify sources of hazards to workers and co-workers. The types of hazards EH staff may encounter include:
Environmental Health (EH) practitioners should become familiar with the types of PPE that may be required to protect against potential hazards encountered during human health hazard investigations, and should be aware of situations when the use of PPE is necessary. EH practitioners must also be able to determine when the PPE they have available is inappropriate and may not provide sufficient protection. There are OSHA standards on the specific types of PPE commonly used by EH and public health workers:
At a minimum, the investigation of human health hazards often requires the wearing of common PPE and protective clothing to protect feet (boots or heavy shoes), eyes (safety glasses), hands (safety gloves, disposable nitrile or latex-free gloves), body (Tyvek® suits or gowns), and head (hard hat). This gear may not be appropriate for all situations, but having access to this equipment will assure it is available when needed.
For situations involving chemical spills, hazardous materials, confined spaces, or criminal activity, EH practitioners and public health workers, unless specifically trained to respond to the type of incident observed, should refer the situation to a local fire department Hazardous Materials (Haz Mat) team, law enforcement officials, or the regional Wisconsin Department of Natural Resources (DNR) Chemical Spill Coordinator.
For environmental health exposures, the use of standard precautions refers to general contact control practices that prevent contamination of the skin, eyes, mucous membranes, and clothing. These precautions should be observed when contact with potentially hazardous materials, body fluids, fecal material, and other environmental contaminants is a possibility. The following standard precautions should be used during environmental investigations:
Examples of PPE Use for Environmental Health Investigations
Frequently Asked Questions for Environmental Health PPE
When should I wear a respirator for a human health hazard exposure investigation, and what type do I need?
When conducting investigations where there is a lot of dust and debris present, such as in home renovations, construction sites, and disaster clean-up 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, a 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).
I have to investigate an odor complaint at a large farm, and will be using a meter to check gas levels. What PPE do I need?
Most farm odor problems involve the release of gases, so use of an N95 particulate respirator will not protect you from any gases present. A 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 would include: boots/shoes with shoe covers; Tyvek® suit to protect from manure and/or agricultural chemicals; and eye protection (if very dusty).
I have to investigate a house that is in poor condition. What do I need?
Prior to entry 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. A 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.
I need to determine if a home is habitable after a flood. What PPE is needed?
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 work boots 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, a N95 respirator should also be worn to protect against mold spores.
I have been asked by law enforcement to assess an illegal methamphetamine laboratory (meth lab). What do I need for PPE?
Prior to 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 they have 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.
I have been asked to help assess the risk of a mercury spill. Can I do that?
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 to mercury vapors. Use a Tyvek® suit, shoe covers, and nitrile gloves for PPE. Consult with Wisconsin Division of Public Health Environmental Health staff prior to beginning the investigation.
I am investigating a hoarding/dirty house complaint and animal waste is everywhere. What PPE should I use?
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 a 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.
If you have any questions, e-mail Ryan Wozniak at firstname.lastname@example.org