Fit testing face masks to avoid transmission: Coronavirus (COVID-19)

Fit testing face masks to avoid transmission during the Coronavirus (COVID-19) pandemic

Respiratory protective equipment

Tight-fitting respirators (such as disposable FFP3 masks and reusable half masks) rely on having a good seal with the wearer’s face. A face fit test should be carried out to ensure the respiratory protective equipment (RPE) can protect the wearer.

Minimise the risk of transmission

People who have symptoms of COVID-19 or are isolating in accordance with government guidance should not attend a face fit test.

To minimise the risk of transmission of COVID-19 during face-fit testing the following additional measures should be taken:

  • both the fit tester and those being fit tested should wash their hands before and after the test in accordance with NHS guidelines
  • those being fit tested with non-disposable masks should clean the mask themselves before and immediately after the test using a suitable disinfectant cleaning wipe (check with manufacturer to avoid damaging the mask)
  • test facepieces that cannot be adequately disinfected (e.g. disposable half masks) should not be used by more than one individual. 
  • fit testers should wear disposable gloves when undertaking cleaning of the tubes, hoods etc and ensure they remove gloves following the correct procedure
  • immediately dispose of used gloves, disposable masks, cleaning wipes etc in a waste bin.

Fit testers should familiarise themselves with the following potential contact points and actions to minimise transmission:

  • Inside and outside of respirator (mask) - The wearer should clean the inside and outside of the mask using a suitable disinfectant cleaning wipe under the fit tester’s instruction and supervision.
  • Inside and outside (where held) of hood used for qualitative fit tests - The fit tester should clean the inside and outside (where held) of the hood between each test using a suitable disinfectant wipe that won’t damage the visor and wearing disposable gloves.
  • Moisture from the wearer’s breath collected inside the ambient particle counting device tubing (i.e. for quantitative testing) -  Only touch used tubing when wearing gloves. Clean the mask end of the tube with a suitable disinfectant wipe after use. Have a stock of spare tubes (to allow used tubes to dry); or ensure the end of used tubing is placed in a wad of tissue if removing the condensate between tests by blowing out with compressed/canned air.
  • Fit testing adaptors and sampling probe - Clean at the same time as cleaning the mask following the fit test using a suitable disinfectant cleaning wipe, under the instruction and supervision of the fit tester.
  • Specific inner mask supplied by fit tester when fit testing powered RPE and the existing inner mask is replaced - This should be cleaned by the wearer at the same time as they clean the inside of the mask using a suitable disinfectant cleaning wipe following their fit test, under the instruction and supervision of the fit tester.
  • Filters - Although, the wearers exhaled air does not pass through the filters used when testing half and full facemasks, they may be re-used and handled between tests and so should be wiped using a suitable disinfectant cleaning wipe.

Further advice on fit testing

A fit test should be carried out before people wear RPE for the first time. Inadequate fit can reduce the protection provided and lead to immediate or long-term ill-health or can even put the RPE wearer’s life in danger. A fit test should be repeated whenever there is a change to the RPE type, size, model or material or whenever there is a change to the circumstances of the wearer that could alter the fit of the RPE; for example:

  • weight loss or gain
  • substantial dental work
  • any facial changes (scars, moles, effects of ageing etc) around the face seal area
  • facial piercings
  • introduction or change in other head-worn personal protective equipment (PPE)

There is no stipulated frequency for re-testing, and you don’t need one if there are no changes in these circumstances.

More detailed guidance is available on the respiratory protective equipment section of our website.