Technical breathing air is required in closed or poorly ventilated rooms where the air quality is insufficient, e.g. when painting, welding or working in pressurized containers. In fire protection, breathing apparatus with technical breathing air is used to protect against smoke and toxic gases. In mining, respiratory protection is required to work in oxygen-poor or contaminated environments. Technical breathing air is also required in chemical orphysical laboratories where hazardous substances areprocessed.

The Occupational Safety and Health Administration (OSHA) plays a central role in establishing and enforcing requirements for breathing air quality in US work environments. In 29 CFR 1910.146, OSHA stipulates that the oxygen content in work areas must be between 19.5 % and 23.5 %. The CGA G-7.1-2018 standard (recognized by OSHA) defines limit values for pollutants such as CO, CO₂ and oil mist. In critical areas (e.g. confined spaces or fire protection systems), OSHA requires the use of monitoring systems todetect oxygen deficiency or the accumulation of pollutants atan early stage.