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Boxes of N95 respirators

Get your PPE such as NIOSH-approved N95 masks and face shields from Safety Emporium.


A respirator (of the "approved" type) is a device which has met the requirements of 42 CFR part 84, has been designed to protect the wearer from inhalation of harmful atmospheres, and has been approved by the National Institute for Occupational Safety and Health (NIOSH) and the Mine Safety and Health Administration (MSHA).

Note: 42 CFR part 84 supercedes/replaces 30 CFR part 11, effective July 10, 1995. The change dealt primarily with particulate respirators. See for details.

Additional Info

There are many different kinds of respirators used to prevent or reduce inhalation of hazardous or toxic materials. These fall into two general classes:

  1. Atmosphere-supplying respirators. These respirators provide breathing air from a source independent of the surrounding atmosphere. Three types of atmosphere-supplying respirators are:

    a pictureAir-line respirators (also called an air-supplied respirator or supplied air respirator, SAR). The respirator is connected to a stationary source of compressed breathing air source by a hose. The air is delivered continuously or intermittently in a sufficient volume to meet the wearer's breathing requirements. Obviously, the user is restricted by the length of the hose connection, and the dangers of damage to the hose. Also see this OSHA article, Deaths Involving the Inadvertent Connection of Air-line Respirators to Inert Gas Supplies.

    a pictureSelf-contained breathing apparatus (SCBA). This is much like the apparatus a SCUBA diver or fire fighter might use. Air is supplied from a compressed cylinder, usually through a full-face mask, which is worn on the back. This gives greater movement than an air-line respirator, but the air supply is limited.
    a pictureCombination respirators have a small, auxiliary self-contained air supply that can be used if the primary supply fails.
  2. Air-purifying respirators. These contain an air-purifying filter, cartridge, or canister that removes specific air contaminants by passing ambient air through the air-purifying element. These do not supply oxygen and must only be used when there is sufficient oxygen to sustain life and the air contaminant level is below the concentration limits of the device.
  3. In addition, these cartridges/canisters usually do not include any method of indicating when their ability to remove air contaminants has been reduced. Read the manufacturer's instructions for cartridge maintenance and replacement or see the OSHA link below.

    There are three basic kinds of air-purifying respirator.

    a pictureParticulate respirators use a mechanical filter to remove particulate matter such as dusts. Do not assume that your respirator removes particulates or vapors; READ the labels and manufacturer's instructions. NIOSH has a discussion of particulate filtering classification, marking, and approved labels that explains what terms like N95, R99, and P100 mean. Note: Ear loop surgical-style masks are not classified as respirators. These do not provide a good seal and are generally unacceptable for protection from particulates in occupational settings.
    a pictureGas and vapor respirators (or chemical cartridge respirators) use chemicals such as activated charcoal to remove specific gases and vapors from the air. These are effective for concentrations of no more than ten times the TLV of the contaminant, if the contaminant has warning properties (odor or irritation) below the TLV.
    a pictureCombination respirators have filters for both particulates and vapors.
    Powered air-purifying respirators (PAPR) (not shown) use a blower to force the ambient air through air-purifying elements to the inlet covering.

Some other respirator terms worth knowing are:

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SDS Relevance

safety poster

Safety posters are a terrific way of reminding employees of proper procedure. Get yours at Safety Emporium.

If the material you are working with requires the use of a respirator, this information will be found in Section 8 (exposure controls/personal protection) of the Safety Data Sheet. If the SDS author was competent, a specific type of respirator will be recommended for the particular hazard.

Respirators should be used for protection only when engineering controls (for example, enclosure or confinement of the operation, general and local exhaust ventilation (such as fume hoods), and substitution of less toxic materials) have been shown to be infeasible for the control of the hazard or during the interim period when engineering controls are being installed.

Keep in mind the following facts about respirators:

Further Reading

Dust mask dispenser

Make your PPE readily available with safety dispensers from Safety Emporium.

See also: asthma, emphysema, fume hood, respiratory.

Additional definitions from Google and OneLook.

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