Types of Respirators

Following is a description of the various types of respirators available for use at UCSC. Included in the discussion is a brief overview of the advantages, disadvantages, limitations, applications and assigned protection factors for each class of respirator.

Disposable Dust/Particulate Respirators
Description: Most single use disposable particle masks (double strapped types) are designed to protect the lungs from nuisance particals as well as certain pneumoconiosis, fibrosis-producing dusts and mists. Currently the Natural Sciences Stockroom sells 3M 8710 and 3M 9913 type masks. The Campus Facilities Store sells Moldex 2300 and 3M 8710 masks.
Advantages: Respirators are lightweight, disposable, relatively comfortable, and inexpensive.
Limitations: Disposable dust respirators offer minimal protection due to poor sealing characteristics. They cannot be used by personnel with facial hair which comes between the respirator and the skin. These types of respirators are frequently misused therefore EH&S or your supervisor should be consulted prior to use.
Applications: Low concentrations of nuisance dusts, mists, pollen, and animal dust as well as some pneumoconiosis and fibrosis-producing dusts and mist such as coal dust.
Assigned Protection Factor = 3 - 5
(Each style of mask identified above is approved for protection against dusts and mists whose Permissible Exposure Level is >= 0.05 mg/m3. However, under some circumstances, these masks have been shown to be as little as 35% efficient. Therefore be sure them with caution and full understanding of the respiratory hazard)
Particulate Respirators - N. R. P. Series

Description: Effective July 1995 new performance criteria were established for particulate respirators. The new criteria eliminates classification of particulate filters according to hazard such as "dust mist fume" and provides for three levels of filter efficiency (95%, 99%, 99.97%).These efficiencies are available in a series of filter types known as N, R, and P (see the table below). These new respirators will afford a higher level of protection to a variety of workers including hospital employees needing protection from infectious tuberculosis, carpenters, painters, and farmers. NIOSH has established a three year transition period for instituting the new regulation. After July 10, 1998 all particulate respirators will have to be certified under the new criteria.


NaCl Test Aerosol

DOP Test Aerosol (oil resistant)

DOP Test Aerosol (very oil resistant)













Be sure to contact EH&S if you need more information on these types of respirators.

Air Purifying Half Mask Respirators
Description: Air purifying, half mask respirators have a rubber face seal which fits over the nose and under the chin. It is fitted with cartridges which purify the air as the wearer breathes. Different types of cartridges are available for different types of air contaminants.
Advantages: Relatively lightweight and offer good protection from many air contaminants.
Limitations: Air purifying respirators cannot be used for all types of air contaminants and are limited by the type and capacity of the filters/cartridges used. Protection factors offered by these masks is not as good as that provided by a full facepiece air purifying respirator nor do they provide eye protection. Proper fit is essential and many factors may effect the face to facepiece seal. They cannot be used in oxygen-deficient atmospheres, or in atmospheres which have high concentrations of contaminants. Breathing may become difficult because of the additional effort required to draw air through the purifying media.
Applications: Air purifying respirators can be used for protection from a wide variety of respiratory hazards. Cartridges and filters are designed to provide protection against a specific type of hazard. The most common types of cartridges are:
HEPA Cartridge - for low level concentrations of certain toxic dusts including asbestos, radionuclides and silica.
Organic Vapor Cartridge - are approved for concentrations not to exceed 1000 ppm for many organic solvents, petroleum distillates, and alcohols.
Acid Gas/Mist Cartridge - for atmospheres containing low levels of mineral acid gas or mist.
Pesticide - for low levels of pesticide vapors or mists.
Combination Cartridge - for environments with more than one contaminant present (e.g. organic vapors, acid gasses, and particulates.
Mercury Cartridge - for protection against low levels of metallic mercury vapors.
Assigned Protection Factor = 10
Air Purifying Full Facepiece Respirators
Description: Air-purifying full facepiece respirators work on the same principal as the half-mask respirators described above. The facepiece extends around the entire face, covering the eyes, nose, chin and mouth.
Advantages: Full facepiece respirators provide a better seal and therefore, more protection than half-mask air-purifying respirators. They also protect the eyes and face from irritating vapors, mists, and splashed chemicals.
3. Limitations: Full face respirators are heavier than half-masks and often less comfortable for the wearer. Full face air purifying respirators cannot be used for all types of air contaminants and are limited by the type and capacity of the filters and cartridges used. Eyeglass wearers must assure that temple bars do not interrupt the face to facepiece seal. They cannot be used in oxygen-deficient atmospheres, or in atmospheres which have high concentrations of contaminants. Breathing may become difficult because of the additional effort required to draw air through the purifying media.
Applications: Full face respirators are used where a greater degree of respiratory protection is needed or where eye and face protection is desirable.
Assigned Protection Factor = 50.
Powered Air Purifying Respirators (PAPR)
Description: This class of respirators feature a battery powered, portable fan which draws air through a particulate or chemical filter and blows it to the facepiece. The fan and filter unit may be an integral part or the facepiece or mounted on the wearer's back or belt. Full and half-mask facepieces are available as well as a variety of helmets and hoods.
Advantages: Major advantages are derived from the positive pressure provided by the fan forcing air into the facepiece, hood or helmet. This eliminates difficulty in breathing provided by negative pressure respirators and reduces the importance of a good facial fit.
Limitations: Units are relatively expensive to purchase and maintain. Use is restricted to battery life and the fan and battery pack must be carried by the wearer at all times. They cannot be used in atmospheres deficient in oxygen or other IDLH atmospheres. Heavy exertion (breathing) may create negative pressure inside the facepiece reducing the respirator's effectiveness.
Assigned Protection Factor = 25 - 100.
Airline Respirators (Pressure Demand or Continuous Flow)
Description: These respirators provide clean, fresh air to the wearer from a stationary source such as a compressor or compressed air cylinders. They may be equipped with a half or full facepiece, helmet, or hood. Breathing air must be high quality and meet regulatory specifications. Air-line respirators have limited application on the UCSC Campus. The use of this type of respirator shall be approved on a case by case basis by EH&S.
Advantages: Airline respirators may be used for long periods of time and provide a high degree of protection from a variety of air contaminants. they provide minimal breathing resistance and discomfort, are light weight, low bulk, moderate initial cost and low operating costs. These respirators can be used in oxygen deficient and other IDLH atmospheres when used in conjunction with a 5 minute self-contained air supply (escape respirator).
Limitations: Loss of the source of air eliminates all protection to the user. Air must be delivered to the mask or hood through a hose which can be awkward to maneuver and may easily tangle or crimp.
Applications: These respirators can be used for protection from most all air contaminants.
Assigned Protection Factor = up to 10,000
Self-Contained Breathing Apparatus (SCBA)
Description: SCBA's provide the user with clean air from a high pressure cylinder carried on the wearer's back. They are equipped with a full facepiece and are operated in the pressure demand mode. SCBA's provide the maximum degree of protection available from airborne contaminants.
Advantages: Users carry their air supply with them allowing comparatively free movement over an unlimited area.
Limitations: SCBA units are expensive to purchase and maintain; require the wearer to carry 20 to 30 pounds of equipment on their backs, and provide no more than 40 minutes of continuous use. Personnel with facial hair which comes between the respirator sealing surface and the wearer's face cannot use SCBA equipment.