Qualitative fit testing is often seen as the poor mans alternative to quantitative testing. However during a recent batch of testing we carried out for a client, we were reminded of the unique advantages of the qualitative method.
It is often difficult to appreciate how well your respiratory protection is working when fitted correctly and conversely how that protection is reduced if the mask is worn incorrectly. Often a wearer will not be aware of the contaminates in the atmosphere they are working and will not appreciate the need to correctly fit their mask or even to wear it for the duration of their task.
Qualitative testing uses a bitter tasting but harmless solution (Bitrex). The wearer puts in their mask underneath a hood that covers their head and shoulders. At intervals during the test, as the wearer is carrying out a series of exercises, the tester sprays the Bitrex solution into the hood. If the wearer can taste the Bitrex then their mask either does not fit or has not been fitted correctly.
At the end of the test the wearer (still wearing the hood) will reach up inside and gently lift the mask away from their face and immediately detect the bitter taste of the Bitrex.
The reaction of the wearer at this point is usually one of suprise! Wearers typically have no idea that the concentration of Bitrex has built up inside the hood and are amazed that their mask has managed to filter out all of the aerosol.
"I never knew the masks were that good!"
"Can't believe you have been spraying that stuff for the last few minutes and I hadn't realised!"
"Thank you for the testing you have carried out recently. [My colleague] tells me that the lads all passed and we have had good feedback regarding the testing. The lads are more understanding of our clean shaven policy now."
CSTS offers a qualitative and quantitative fit testing service which can be carried out at your premises or one of our training centres. Testing can be combined with a short training session on the particular masks in use, including their care, use, limitations, donning and doffing procedures.
To book an individual test or group session
To book just call us on 01925 244144 or email us on email@example.com and we'll guide you through the process.
Sources of further information
The HSE document, 'INDG 460, Is Your Mask Protecting You?' has some useful tips for wearers.
The HSE document, 'Fit Testing of Respiratory Protective Facepieces, OC282/28', gives information on the legal requirement for testing and lays down the protocol for carrying out a test.
The HSE document, 'HSG 53, Respiratory Protective Equipment at Work', gives guidance on the selection and use of RPE.
Our information page contains news, legal requirements and free downloads - www.csts.co.uk/face-fit-explained/