Self-contained breathing apparatus (SCBA) or CABA with a demand valve full-face mask

Last reviewed on 04/08/2014 10:12

Self-contained breathing apparatus (SCBA) or CABA with a demand valve full-face mask


  • SCBA is highly specialised equipment. The wearers require high levels of training for safe use
  • SCBA is fitted with a full face mask and a demand valve to provide a small positive pressure inside the mask
  • A 'Demand valve' is designed to provide air flow as demanded by the wearer
  • The BA can be cleaned and reused many times, as recommended by the manufacturer
  • It may be worn continuously for more than 1 hour
  • SCBA is suitable for use in oxygen deficient atmospheres, and in harsh and demanding environments
  • It is used for short term work such as work in tanks, trenches and sewers
  • Precautions and safety procedures are required for safe use. These come with training, experience and knowledge of the harsh environment
  • This BA is OK for medium work rate (work involving sustained hand and arm movements, or similar to brisk walking)
  • It is also OK for a heavy work rate (heavy manual work requiring a lot of exertion and energy)


  • Establish the time limit - the duration for safe use
  • Set up a reliable system for communication
  • Set up a check-out and check-in procedure for SCBA
  • Select the right size mask for each wearer. Fit-testing for each wearer is required when using this RPE for the first time
  • Fit the straps as recommended
  • Ensure that wearers check the RPE fits correctly every time, as recommended by the manufacture
  • Ensure that the compressed air quality meets the minimum requirements of BSEN12021


  • Keep working beyond the safe working time
  • Continue to work if any warning signal sounds
  • Store SCBA in a dirty area or a dirty state
  • Use unserviced or dirty equipment
  • Use solvents to clean the mask, straps or hoses
  • Make DIY modifications to the RPE