Respiratory Protection - Biosafety Occupational Health Program (BOHP)

The Texas A&M University (TAMU) Biosafety Occupational Health Program (BOHP) provides respiratory protection services to personnel at risk of exposure to infectious biohazards or to animal allergens during their participation in, or operational support of, Institutional Biosafety Committee (IBC) or Institutional Animal Care and Use Committee (IACUC) permitted research, teaching, or diagnostic activities.

Types of Respiratory Protection

Respiratory protection is a type of personal protective equipment (PPE) used prevent an individual from inhaling harmful substances such as particulates, vapors, and gases. Ideally, engineering controls should be in place to mitigate the risk of exposure to respirable hazards. When engineering controls are not feasible or insufficient, the individual should use the appropriate form of respiratory protection. 

There are different types of respirators, and each respirator type provides a different level of protection based on its design. It is important to choose the right type of respirator for the specific exposure you may have.

Air-Purifying Respirators –

  • Particulate Filtering Facepiece Respirator (e.g., an N95 disposable respirator)
    • Disposable
    • Covers the nose and mouth
    • Filters out airborne particles such as animal dander and infectious pathogens
    • Does NOT provide protection against gases, vapors, oil-based mists, chemicals, or unknown contaminants
    • Should not be worn in an oxygen deficient atmosphere
    • Fit testing required
  • Elastomeric Half Facepiece Respirator
    • Reusable facepiece and has replaceable cartridges or filters
    • Covers the nose and mouth
    • Protects against gases, vapors, or airborne particles if equipped with the appropriate cartridge or filter
    • Fit testing required
  • Elastomeric Full Facepiece Respirator
    • Reusable facepiece and has replaceable canisters, cartridges, or filters
    • Provides eye protection
    • Protects against gases, vapors, or airborne particles if equipped with the appropriate cartridge, canister, or filter
    • Has a more effective face seal than a filtering facepiece respirator or an elastomeric half facepiece respirator
    • Fit testing required
  • Powered Air-Purifying Respirator (PAPR)
    • Reusable components and replaceable filters or cartridges
    • Protects against gases, vapors, or airborne particles if equipped with the appropriate cartridge, canister, or filter
    • Battery-powered with blower that pulls air through attached filters or cartridges
    • Provides eye protection
    • Low breathing resistance
    • Loose-fitting PAPR does not require fit testing and can be used with facial hair

Respiratory Protection Medical Clearance

Wearing respiratory protection may place a physical burden on an individual; the burden varies on the type of respirator that is being worn, the workplace conditions, and the health status of the individual. To mitigate risk(s) associated with wearing respiratory protection, individuals must be medically cleared to wear a respirator on an annual basis.

First time respiratory protection users must complete the initial respiratory protection medical clearance questionnaire, which is reviewed by the University’s Occupational Health Provider (OHP). Each year thereafter, the individual must complete the annual respiratory protection medical clearance questionnaire short form. Based on questionnaire responses, the individual may be prompted to complete additional items before being cleared to wear respiratory protection (e.g., complete a pulmonary function test).

Fit Testing

Individuals complete a fit test to ensure the respirator they will be wearing fits comfortable and will provide adequate protection.

There are two types of fit testing, qualitative fit testing, and quantitative fit testing. Qualitative fit testing utilizes an individual’s senses (taste or smell) to determine if there are any gaps between the seal of the respirator and the individual’s face. Quantitative fit testing uses an instrument (e.g., a portacount machine) to provide numerical measurements of the amount of face seal leakage occurring while the individual is wearing the respirator.

Individuals must be fit tested on an annual basis to ensure the make and model of respirator they are using still fits and is providing adequate protection. Certain events can require an individual to be fit tested again prior to their annual renewal date:

  • Personal concern that the respirator is not sealing tightly against the individual’s face
  • Obvious change in body weight –
    • Weight loss of 20 pounds or more has been shown to affect the fit of a respirator in about a quarter of respiratory protection users (Zhang 2016); however, all individuals are built differently – for some, weight loss less than 20 pounds could impact the fit of their respirator
  • Change in dentition (tooth loss or replacement)
  • Change in facial bone structure (bone breaks, reconstructive or cosmetic surgery)

Individuals that choose to wear more than one make or model of respirator must be fit tested on each respirator they plan to wear.

During the fit test, an individual can expect the following –

  • To complete a series of breathing exercises while wearing the respirator
  • Training on the following:
  • How to inspect the respirator to ensure it is not damaged
  • How to properly put on and take off the respirator
  • How to perform a seal check
  • How to recognize medical signs or symptoms that could limit or the prevent the effective use of the respirator

How to Prepare for a Fit Test

Individuals must have current medical clearance prior to being fit tested (see Respiratory Protection Medical Clearance section for additional details).

Individuals must be clean shaven on the cheeks, chin, and neckline. Facial hair must not extend beyond the corners of the mouth, nor be so long or thick that it could prevent the respirator from properly sealing to the face.

Do not use tobacco products one hour prior to being fit tested.

Take the following to the fit testing appointment:

  • The respirator(s) you will be fit tested on
  • If you will wear prescription eye ware (e.g., glasses) or eye protection (e.g., safety goggles) while wearing a respirator, take those items with you to your appointment. To ensure eye ware does not interfere with the seal of the respirator, it should be worn during the fit test.

Maintaining and Storing a Respirator

Prior to wearing a disposable respirator, inspect the respirator for the following:

  • Elastic straps – check for loss of elasticity, tears, aging/crumbling
  • Metal nose clip – ensure it is not broken
  • Filter – check for holes and tears

Prior to wearing an air purifying respirator, inspect the respirator for the following:

  • Rubber facepiece – check for excessive dirt, cracks/tears/holes, distortion from improper storage, cracked/scratched/loose-fitting lens, broken/missing mounting clips, worn threads in filter holder, missing/worn gaskets in filter holder
  • Head straps – check for breaks, loss of elasticity, broken/malfunctioning buckles, or attachments
  • Inhalation and exhalation valve – check for buildup of residue/dust particles/dirt, cracks/tears/distortion, missing/defective valve cover
  • Particulate filters – proper filter/canister for the hazard, approval designation, worn threads on filter housing, cracks/dents in filter housing, service life indicator/expiration date (if it has one)

Respirators should be safely stored in an area that is free of dust, sunlight, heat, extreme cold, excessive moisture, and chemicals.

Respiratory Protection Malfunction

If you experience the following, leave the lab space immediately (make sure to follow proper exit protocols):

  • Respirator fails (a strap breaks, the respirator has become dislodged, etc.)
  • A chemical or burning smell or taste
  • Irritation of the nose or throat
  • Physical stress – breathing difficulty, dizziness, or nausea

Once safely out of the lab, contact your Principal Investigator or Supervisor, inform them of what has occurred, and follow up with the BOHP at Do not re-enter the area that requires use of respiratory protection until the problem has been identified and resolved.

Contact Information

Contact the BOHP at for questions or concerns regarding respiratory protection services for mitigating risk(s) of exposure to infectious biohazards or to animal allergens.

Contact Environmental Health and Safety at for questions or concerns regarding respiratory protection services for mitigating risk(s) of exposure to chemical hazards.

Additional Resources

Source: National Institute for Occupational Safety and Health; 1910.134 – Respiratory protection. | Occupational Safety and Health Administration (; Fit Test FAQs | NPPTL | NIOSH | CDC; Texas A&M University Respiratory Protection Program; N95 Fit Test Infographic (; Types of Respiratory Protection | NPPTL | NIOSH | CDC; 1910.134 App A – Fit Testing Procedures (Mandatory). | Occupational Safety and Health Administration (