From time to time someone sends in a question about using compressed air for breathing air. They are asking about the air flow, what size of air tube or air line, or at what air pressure should they use to supply compressed air for breathing air.
And often, this question comes from folks that have a workshop air compressor, and want to be able to breathe other than paint fumes and paint while they spray paint something.
The short and simple answer is… DON’T!
Here’s why. Compressed air that is coming from an industrial or DIY type air compressor is not suitable for breathing.
Lubed-for-life air compressors have factory lubrication in the pump. Some of that gets into the air stream, into the tank, and into the air lines.
Air compressors that have added oil impart some of the oil to the air stream.
The intake filter on the compressor pump removes much of air borne debris, but it does not remove it all. That dust, of indeterminate origin, gets into the tank and into the air stream.
The inside-tank coating will deteriorate over time, and some of that, too, will get into the flow of air.
Air compressors generated water from the air as they compress air into the tank. That water mixes with all of the crud that is already in the tank, and some of that mixture gets into the air stream from the tank.
Any time a compressed air driven paint or chemical sprayer is used paint and chemicals are sprayed into the air and onto the work piece. Some of the atomized paint and chemicals will make its way to your mouth and nose, along with the compressed air that is driving it, and you will inhale it.
OSHA (Occupational Safety and Health Administration) confirms this, as stated on their website: “Hazardous breathing conditions exist in many routine industrial operations, such as chemical manufacturing, hospitals, abrasive blasting, paint spraying, industrial cleaning, and arc welding. In these and other operations that introduce contaminants into the workplace, supplied-air respirators, air filtration systems and carbon monoxide monitors are frequently used for worker protection.” (OSHA website)
Yeah, but can I breathe air from my compressor?
The answer is still no, UNLESS you add sufficient air-treatment equipment to an air line from an industrial air compressor that will prepare the air for breathing.
Some of the equipment necessary to clean compressed air to breathing quality includes – but is not limited to:
- general purpose 40 micron air filter (to remove larger particulates and free water)
- finer element 5 micron air filter (to filter finer particles from the air and further remove free water)
- air dryer (to remove water vapor)
- coalescent filter (to remove oil mist from the air)
You do want to make sure you prepare the air properly. A good source for information on what air preparation equipment is necessary to use compressed air for breathing air is the same OSHA website.
Note that this equipment only cleans the air coming fro the compressor tank. It does not clean the sprayed paint that clouds the nozzle of the paint spray can or spray gun, and fills the room with aerosol paint. For that, you’ll need a breathing mask to accept cleaned air so that the person spraying paint can breathe clean air.
Otherwise, if you are contemplating breathing air from a mask that is being supplied by non-treated compressed air, you are risking your health, if not your life.