BS 8478:2011

This standard BS 8478:2011 Respiratory protective devices. Breathing gases for diving and hyperbaric applications. Requirements and test methods is classified in these ICS categories:

• 13.340.30 Respiratory protective devices
• 97.220.40 Outdoor and water sports equipment

This British Standard specifies requirements and test methods for the composition and purity of breathing gases, other than compressed air as specified in BS EN 12021, for use in diving and hyperbaric applications.

The standard is applicable to the following categories of breathing gas mixtures:

1. breathing oxygen;

2. oxygen compatible air;

3. nitrogen depleted air;

4. oxygen and nitrogen gas mixtures;

5. oxygen and helium gas mixtures;

6. oxygen, helium and nitrogen gas mixtures.

The standard also specifies requirements and test methods for the purity of helium for use in making breathing gas mixtures.

The standard is not applicable to compressed gases for medical use, or to gases for use in high altitude breathing apparatus.

NOTE The composition and purity of compressed air is specified in BS EN 12021.