Qualitative fit testing

Editor – We recently spent 7 weeks coordinating qualitative fit testing (QFT) of FFP3 masks at a major London hospital site. Upon reflection, we believe that fit testing within the NHS should be routine.

Although adequate respiratory protective equipment (RPE) is required for protection from COVID-19 transmission, QFT should already be the norm for NHS workers.^1,2 RPE is worn in intensive care, theatres, respiratory wards or side rooms to prevent transmission of various airborne diseases. Although RPE has been proven effective, adequate protection requires prior fit testing and depends upon a ‘good fit’.^3–5 Many staff who have worn RPE regularly are only now undergoing QFT for the first time, which highlights a systematic failure of the NHS to protect its workers.

Some research has also suggested that certain facemask models are more suited to male and Caucasian face shapes.^6–8 This is important, given the higher rates of COVID-19 cases among black and minority ethnic staff.⁹ Of the eight different models of mask that we tested, none had a perfect fit rate and only one had a fit rate above 60%: variety is key. Costs and strain on suppliers have limited the variety of masks in hospital sites; however, the range of masks available must reflect the varied demographics across the NHS workforce. Regular QFT before the pandemic would have allowed fit rate comparison between models, and stock could have been prioritised accordingly.

We urge the NHS to review its fit testing policy. Trusts could routinely perform QFT on new staff members, using multiple facemask models to account for changes in availability. Individuals could keep a record of their QFT results so that if they move between sites, they have evidence stating which mask(s) fit and, thus, should be provided by the new site. Finally, NHS trusts could perform regular analysis of anonymised fit testing data and assessment of stock to ensure that all staff, regardless of gender or ethnicity, are adequately protected.

We make these proposals on the grounds of improved public health measures for this country and acceptable working conditions for NHS staff.