Environmental, Health and Safety Services

Respirator Selection Procedures

EHSS will select appropriate respiratory protection in accordance with applicable regulations and based on the Respiratory Hazards Assessment form. This form, completed by either the Supervisor/Principal Instructor/Professor and/or EHSS, may be used in conjunction with EHSS observation of worker job tasks and/or personal monitoring to identify respiratory hazards of concern. After the hazard evaluation, EHSS personnel will recommend the type of respirator and cartridges to be used and discuss different options with the supervisor and the respirator user.

 All respirators worn by Virginia Tech employees and students must be certified by the National Institute for Occupational Safety and Health (NIOSH) and must be used in accordance with the terms outlined by EHSS. All filters, cartridges and canisters must be labeled with the appropriate NIOSH approval label that must not be removed or defaced at any time while the respirator is in use. Interchanging of respirator parts (valves, cartridges, air tubes or hoses, etc.) is not permitted and voids the NIOSH certification for a given respirator.

Types of Respirators

There are two primary types of respirators available: air purifying respirators and air supplying respirators.

 Air-Purifying Respirators

Air-purifying respirators can be used when it is necessary to remove particulates and/or vapor and gas contaminants from the air and their concentration is within the maximum use concentration (MUC) of that respirator as determined by EHSS. For non-infectious bio-aerosols (bacteria, molds, allergens) and infectious bio-aerosols (viruses, pathogenic bacteria), respirator selection will be determined on a case by case basis. An N-series disposable filtering facepiece or a PAPR may be required.

Air-purifying respirators are not effective in oxygen deficient atmospheres or in atmospheres that are Immediately Dangerous to Life and Health (IDLH), and must not be used in these environments. PAPRs with HEPA filters do not protect against chemical vapors or gases. It is also important to note that there are some chemicals in the gaseous or vapor form for which no cartridge offers sufficient protection. Therefore, always consult with EHSS before deciding on the type of respiratory protection needed.

 Air Supplying Respirators

Air supplying respirators provide the user with respirable air drawn from a separate source, typically a cylinder. These respirators may be used to provide protection in an oxygen deficient atmosphere and/or in a highly toxic atmosphere where air purifying respirators would not be sufficient for reducing the levels of personal exposure. There are two types of air supplying respirators: Self-Contained Breathing Apparatus (SCBA) and a Supplied-Air Respirator (SAR). Specialized training is required before any Virginia Tech employee is permitted to use these types of respirator. Training must be provided by a contractor certified to teach donning, doffing and use of SARs.

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