BS EN 12941. Respiratory protective devices. Powered filtering devices incorporating a loose fitting respiratory interface. Requirements, testing, marking|Supplied air breathing apparatus, Electrically-operated devices, Helmets (protective), Marking, Designations, Testing conditions, Grades (quality), Fire tests, Filters, Breathing apparatus, Instructions for use, Determination of content, Performance testing, Test equipment, Filtration, Air filters, Accident prevention, Classification systems, Particulate materials, Air, Flammability, Aerosols, Mechanical testing, Leak tests, Respirators, Noise (environmental), Particulate air pollutants, Safety measures, Safety devices, Protective clothing, Strength of materials, Carbon dioxide, Field of vision