Versions of high-pressure industrial air compressors vary from 2,000 to 6,000 PSI. When it comes to breathing air and other purposes, high-pressure industrial air compressors take in air and compress it to pressures of up to 6,000 PSI. The air gets cooled after every level of compression as it goes through the various stages of compression. This cooling is essential to achieve the high pressures required for compression.