Gives minimum requirements for light duty construction compressed air line breathing apparatus, having helmets or hoods, for using in particulate, gaseous or combined contaminated atmospheres. This equipment is meant for use in situations where risk of damage to the compressed air supply tube is low and where the wearer's movements are restricted. Diving and escape apparatus and that used in abrasive blasting conditions are not included. Covers laboratory tests and practical performance tests for assessment of compliance with the requirements.