A new study from the Health and Safety Executive (HSE) exploring the possibility of shortening qualitive fit tests found that quickening the Fit Test method can lead to false pass results and put workers at risk of serious ill-health.
Published in the Journal of the International Society for Respiratory Protection, Mogridge, Bowry and Clayton sought to investigate the effects of shortening the Qualitative Fit Test method in lines with a recent paper by the American National Standards Institute proposing a new 2-minute Quantitative Fit Test method.
Through extensive testing, comparisons and statistical analysis the researchers found that a shorter Qualitative Fit Test fell well below an acceptable level of true passes – leaving people insufficiently protected by their respiratory protective equipment (RPE) and potentially at risk of ill-health or even death.
The study concludes that, while the time a full qualitative fit test takes can be inconvenient, the increase in accuracy of the test and advice/guidance from the trainer is invaluable.
Fit Testing is a practical examination to ensure a tight-fitting respirator mask can achieve a seal around a person’s face and is suitable for an individual. The Quantitative method compares the number of particles inside the mask with the number in the air outside, while the Qualitative method is a pass/fail test that involves the subject tasting (or not tasting) an aerosol solution sprayed into an engineered hood, while undertaking a series of exercises.
Relatively simple to perform, assess and replicate, the Qualitative method is a time and cost-effective way of cascading Fit Testing across large organisations and is subsequently the most commonly used type of RPE test method in the healthcare sector.
However, despite being an effective means of Fit Testing, the process takes around 30 minutes per person from start to finish. With this in mind, the authors wanted to see if the Qualitative Fit Test could be shortened.
“If a shortened qualitative fit test protocol could be validated, its use could help to reduce overall time investment required for an effective fit testing programme [in the healthcare sector].”
Working in conjunction with the National Health Service (NHS) and a number of volunteers, the researchers performed Fit Tests using the standard Qualitative and shortened Qualitative methods for comparison and the Quantitative method for reference and used statistical analysis to assess the results.
Through rigorous testing, the team found that around 70% of poor fits would be expected to fail the shortened Qualitative Fit Test – meaning that some 30% of poor fits would pass, leaving the wearer at risk of harm. This, they point out, is significantly lower than the required 95% rate.
Therefore, the study concludes, the shortened Qualitative Fit Test method that was assessed would not be a suitable alternative.
“While at face value, reducing the time taken for a fit test seems totally sensible, there must be a careful balance struck. Although the test should not be unduly lengthy it is important that sufficient time, resources and commitment – both on the part of the RPE wearer and fit tester – are realised for a fit test to be effective […] There must be a balance between minimising downtime and retaining the essential added benefits of a fit test.”
To read the paper in full, please visit the International Society for Respiratory Protection website: https://www.isrp.com/the-isrp-journal/journal-public-abstracts/881-vol-35-no-1-2018-pp-47-64-mogridge/file