This publication listed coal mine dust personal sampler units, gas detector tube units, and respiratory protective devices certified by NIOSH as of February 28, 1974. The report discussed the purpose of respiratory protective equipment, sampler units, specifications of the sampler units including weight, construction, exhaust, switch, battery, pulsation, beltclips, recharging connection, flow rate indicator, flow rate range, flow rate consistency, and the duration of operation. The conducting of various tests of the equipment was described along with certain applications. Types of protective devices described include self contained breathing apparatus; supplied air respirators; dust, fume, and mist respirators; and chemical cartridge respirators. Names and addresses of manufacturers of approved respiratory protective devices were included.