Another testament to the use of IR on every inspection. How much longer until these circuits caught fire?

Occasionally, we run across compressed air systems in a garage or work shop area. The most commonly used pipe material that we find is Schedule 40 PVC.
The use of PVC pipe is NOT SUITABLE and quite DANGEROUS for use with compressed air. 

It is often used because you can find it at Lowe’s or Home Depot, it’s cheap, and it’s pretty easy to work with. However, it is not recommended for use by the Plastic Pipe Institute, ASTM, nor OSHA because PVC gets brittle over time and can crack, break, or even shatter.
Catastrophic failure of PVC sends razor sharp shards of plastic in all directions.

OUCH!

The presence of air compressor oils in the line and heat from the compressed air accelerates the degradation of PVC. Add all these things together with air under pressure and you have a recipe for disaster.

Galvanized piping is also commonly seen, however it is also NOT RECOMMENDED. 

Pieces of the galvanized coating can flake off and end up in your tools. That can never be a good idea. Commonly, I use compressed air with a blow gun… with galvanized, you have the potential for small shards of metal shooting out… also not a good idea.

Black iron, copper, stainless steel, or aluminum pipes are admittedly more expensive but are much better, and, more importantly, SAFER options!
References: http://www.astm.org/Standards/D1785.htm     https://www.osha.gov/dts/hib/hib_data/hib19880520.html