Inhaled air is drawn through either the air-line (when connected and air is flowing) or through the respirator cartridge (when air is not flowing). The air is then drawn into the facepiece (where it passes over the facepiece lens to minimize fogging) before it is taken into the lungs. Exhaled air then leaves the facepiece through an exhalation valve.

MSA Constant Flow Duo-Twin Respirators are approved by the National Institute for Occupational Safety and Health (NIOSH) and the Mine Safety and Health Administration (MSHA) for use in atmospheres not immediately dangerous to life and health.* These respirators are approved with an inlet pressure range of 35 to 40 psig and with 8-300 ft. of MSA Air-Supply Hose. The respirator requires a source of compressed air conforming to at least Grade D (Compressed Gas Association, Inc., Commodity Specification for Air, G-7.1, which is now ANSI Z86.1-1973).

Asbestos Abatement
Chemical
Construction
Hazardous Materials

Nuisance Odor
Particulate and Dust
Toxic Atmosphere Non-IDLH

Product Information

MSA offers Duo-Twin Air-Line respirators in both Constant-Flow and Pressure-Demand versions. Constant-Flow respirators are normally used where there is an ample air supply such as provided by an air compressor. Pressure-Demand respirators are generally used where only compressed-air cylinders are available. MSA Duo-Twin respirators feature air-purifying cartridges, which also protect against a variety of contaminants. If the air supply should ever fail on the Constant-Flow unit, the user is automatically protected by the air-purifying cartridge. This product is popular in the pharmaceutical, chemical, petrochemical and nuclear industries. The unique Demand/Pressure-Demand (D/PD) switchable exhalation valve, standard on Pressure-Demand models, also makes these units especially well-suited for abatement work. This MSA respirator should not be used in atmospheres containing less that 19.5% oxygen.

Additional Product Information

Technical Information

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