EVS-EN 12021:1999

This European Standard specifies requirements for the quality of compressed air supplied for use with the following types of equipment:  a) Respiratory protective devices - Self-contained open-circuit compressed air breathing apparatus and open-circuit compressed air underwater breathing apparatus (SCUBA);  b) Respiratory protective devices - Compressed air line breathing apparatus and compressed airline breathing apparatus for use under water;  c) Respiratory protective devices for escape - Self-contained open-circuit compressed air breathing apparatus including full face mask or mouthpiece assembly or hoods.  The standard also  applies to synthetic air. Account is taken of the use of air at normal ambient pressures and increased pressures. Maximum allowable concentrations of impurity for compressed air are quoted as values calculated at normal atmospheric pressure.  This European Standard does not apply to compressed air used for medical purposes, for underwater breathing apparatus specially designed to be used for diving in water and other fluids when the hydrostatic pressure exceeds 6 bar absolute or for breathing apparatus designed for use at high altitudes.