A supplied-air respirator (SAR) delivers breathing air from a source outside the work area, so the wearer does not depend on filters or cartridges. That makes it the choice for oxygen-deficient air, very high concentrations, or contaminants no cartridge handles. This guide explains the SAR types, how the air source and hose fit together, and what ERE Inc. supplies in 3M and PIP North supplied-air components.
In this guide
- What is a supplied-air respirator?
- What are the types of supplied-air respirator?
- How much protection does a supplied-air respirator give?
- What air can a supplied-air respirator use?
- Which parts make up an airline system?
- When is a supplied-air respirator the right choice?
- How to choose a supplied-air respirator
- Frequently asked questions
What is a supplied-air respirator?
A supplied-air respirator is a respirator that supplies clean air from a compressed air tank or through an airline, and that air is not taken from the workroom. CCOHS splits respirators into air-purifying types, which clean the surrounding air, and supplied-air types, which replace it. Both tight-fitting facepieces and loose-fitting hoods or helmets are used on an airline.
Powered air-purifying respirators look similar but work the other way round: a blower pulls room air through filters. If you are weighing the two, start with our PAPR guide.
What are the types of supplied-air respirator?
There are airline respirators, which are fed by a hose, and self-contained breathing apparatus (SCBA), which carries the air on the wearer's back. Airline respirators run in one of three modes:
- Demand: air flows into the facepiece only when the wearer inhales.
- Pressure-demand: the facepiece is kept under positive pressure, so any leak is outward.
- Continuous flow: air flows at all times, which suits a hood, helmet or loose-fitting facepiece and keeps the wearer cooler.
Combination units add a cartridge or an escape cylinder as a backup. CCOHS notes that a combination air-purifying and supplied-air respirator protects the wearer if the air supply fails, but cannot be used in oxygen-deficient air or above the IDLH level of a contaminant. The 3M combination dual airline breathing tubes ERE lists, in front-mounted and back-mounted versions, are supplied-air and cartridge combinations.
How much protection does a supplied-air respirator give?
It depends on the mode and the facepiece, and the numbers come from the assigned protection factor (APF) tables. Under the U.S. OSHA 1910.134 Table 1, a continuous-flow airline respirator is rated 50 with a half mask, 1,000 with a full facepiece and 25 with a loose-fitting facepiece. A hood or helmet is rated 25, or 1,000 where the manufacturer has demonstrated it with workplace protection factor testing. A pressure-demand SCBA with a full facepiece is rated 10,000.
These are workplace-level figures that only apply inside a complete respiratory protection program: training, fit testing for tight-fitting facepieces, maintenance and air quality checks. In Canada, confirm the selection rules for your jurisdiction and the CSA respirator standard that applies before you commit to a system.
What air can a supplied-air respirator use?
It must be breathing-grade air. CCOHS states that the air supplied in tanks or from compressors must meet standards for purity and moisture content, citing CSA Z180.1, Compressed breathing air and systems, which sets minimum purity for air delivered to service outlets. Ordinary shop air is not breathing air: oil, moisture, carbon monoxide and particulates have to be controlled by the compressor and filtration, and often monitored.
The PIP North ambient air pump is a different air source. The ambient air pump for continuous-flow respirators (3/4 HP) pushes in the air around it, so it gives no protection against anything in that air. Position it in clean air, away from vehicle exhaust and the contaminant source, and use it only within the approval of the respirator it is connected to.
Which parts make up an airline system?
An airline system is the air source, the hose, a flow-control device, the breathing tube and a headpiece. ERE lists the following supplied-air components from 3M and PIP North, and compatibility with a given headpiece should be confirmed with 3M before ordering:
| Part | What it does |
|---|---|
| 3M Versaflo V-300 valve assembly | Delivers a steady supply of air from a connected compressed air source; adjustable airflow control |
| 3M Versaflo V-400 low-pressure valve assembly | Same role on a low-pressure compressed air source; NIOSH approved; headgear not included |
| 3M supplied air hose | 3/8 in high-pressure hose, 25 ft |
| 3M vortex cooling air control device | Regulates airflow and temperature; cools the air by as much as 27 °C; includes cooling tube, waist belt and holder |
| PIP North airline adapter | Interchangeable breathing tube |
| PIP North ambient air pump | 3/4 HP air source for continuous-flow respirators |
Browse the full range, including Versaflo hoods and helmets, in our PAPR and supplied-air respirators collection, and see the 3M Versaflo guide for the headtops.
When is a supplied-air respirator the right choice?
Choose one when an air-purifying respirator cannot do the job: oxygen-deficient air, contaminant concentrations above what a filter or cartridge is rated for, contaminants with no good cartridge, or long shifts in heavy gear. Typical Canadian uses are abrasive blasting, spray painting and coatings, confined-space work, and remediation or demolition with hazardous dusts or vapours.
If the atmosphere can be immediately dangerous to life or health, the system needs an escape or backup air supply, such as the SCBA combination CCOHS describes. Confined-space entry also needs gas monitoring; see our confined-space gas monitoring guide. For lighter dust jobs a filtering option is simpler, such as the half-mask respirator.
How to choose a supplied-air respirator
- Define the atmosphere. Name the contaminant, its concentration, and whether oxygen is low or the level could be IDLH.
- Pick the mode. Pressure-demand or SCBA for the highest protection, continuous flow for hoods and helmets.
- Pick the headpiece. A tight-fitting facepiece needs fit testing; a hood or helmet does not.
- Secure breathing-grade air. Compressor with filtration to CSA Z180.1, a cylinder bank, or an ambient air pump only where permitted.
- Size the hose and valve. Match the hose length, the high or low pressure valve and the flow control to the supply.
- Plan the program. Training, inspection, air quality checks and an escape plan.
Not sure which combination fits your job? Request a quote and we will match the valve, hose and headpiece, or call us in Montreal.
Frequently Asked Questions
What is the difference between a supplied-air respirator and a PAPR?
A supplied-air respirator brings in air from a source outside the hazard, while a PAPR uses a battery blower to pull room air through filters. A PAPR cannot be used in oxygen-deficient air, and a supplied-air respirator can.
What is the difference between an airline respirator and an SCBA?
An airline respirator is fed by a hose from a remote source and has unlimited duration, but the wearer is tethered. An SCBA carries its own cylinder, so the wearer is free to move but limited by the air in the cylinder.
Do you need fit testing for a supplied-air respirator?
Fit testing applies to tight-fitting facepieces, whether half mask or full facepiece. Loose-fitting hoods and helmets are not fit tested, but the employer still has to run the respiratory protection program.
Can you use shop compressed air for a supplied-air respirator?
Not without treatment. Breathing air must meet CSA Z180.1 purity, so the compressor needs the right filtration and the air must be controlled for oil, moisture and carbon monoxide.
Related articles
- PAPR: how it works and how to choose
- 3M Versaflo guide
- Half-mask respirator guide
- Confined-space gas monitoring
Lire en français : Respirateur à adduction d'air : types, air respirable et composants