This part of ISO 8573 specifies a test method for distinguishing viable, colony-forming, microbiological organisms (e.g. yeast, bacteria, endotoxins) from other solid particles which may be present in compressed air.
DS/ISO 8573-7:2004 history
2004DS/ISO 8573-7:2004 Compressed air - Part 7: Test method for viable microbiological contaminant content