This part of ISO 8573 specifies purity classes of compressed air in respect of particles, water and oil regardless of the source of the compressed air.
This part of ISO 8573 identifies microbiological and gaseous contaminants.
The gaseous contaminants included in this part of ISO 8573 are carbon monoxide, carbon dioxide, sulfur dioxide, nitrogen dioxide, nitric oxide and hydrocarbons with carbon atoms in the range C1 to C5 .
NOTE Other contaminants are taken into consideration for specific applications, e.g.air used for breathing, medical, food and beverage purposes.