USP 1116 – Microbiological evaluation of clean rooms and other controlled environments
ISO 8573-7 Micro Testing of Compressed Air
The International Organization for Standardization (ISO) has developed an international
standard for testing compressed air quality called ISO 8573-1.
This standard measures three types of contaminants in compressed air: water, oil content, and solid particles
It also provides a range of purity classes for particles, water, and oil, but doesn’t include
classes for gases or microorganisms.
Air sampling involves capturing a contaminant from a known volume of air, measuring the
amount of contaminant captured, and expressing it as a concentration. The volume of air is
calculated by multiplying the flow rate through the collection medium by the sample run
time.
Once measured, the contaminants are expressed as milligrams per cubic meter (mg/m3) for
particulates and parts per million (ppm) for gases.