Face fit testing: The essentials
Companies should undertake periodic face-fitting tests on masks because one-off tests do not sufficiently protect workers. Also, masks should have a maintenance record.
HSE guidance dictates that where respiratory protective equipment (RPE) is used, ‘it must be able to provide adequate protection for individual wearers. RPE can’t protect the wearer from . A major cause of leaks is poor fit – tight-fitting facepieces need to fit the wearer’s face to be effective.’
No two faces are the same, therefore it is very unlikely that one particular type or size of RPE facepiece will fit everyone. Fit testing is designed to ensure that the equipment selected is suitable for the wearer.
For more detailed information on fit testing RPE, read the HSE’s publication Guidance on respiratory protective equipment (RPE) fit testing INDG479.
PPE and COVID-19
Medical and fabric masks: Who wears what when?
The World Health Organization (WHO) has published a video outlining when medical masks and fabric masks should be worn in the context of the COVID-19 pandemic.
Importance of periodic face fit testing
Fit testing will need to be repeated when there is a change in equipment or the facial characteristics of the wearer that could affect the fit. Loose-fitting devices, such as powered respirators with a visor or hood, need not be face-fit tested but still need to fit observably close to the face. Therefore, it’s possible that prior to this guidance, workers may only have ever had one face fit test.
HSE’s HSG 53, Respiratory protective equipment at work – A practical guide, published in May 2013, raises some important, related issues around face fitting.
For instance, the guidance says: ‘It is also good practice to have a system to ensure repeat fit testing is carried out on a regular basis. This is especially important when RPE is used frequently as a primary means or exposure control, e.g. annual testing for workers involved in licensed asbestos removal. If there are any changes to a person’s face though, for example, weight loss/gain, scars etc., a repeat fit test will be necessary.’
It is not uncommon that several people within an organisation will wearing a mask which they were originally tested for, but no longer fits. In addition, several people use masks for long periods of time, whereas the HSE guidance states: ‘It is recommended that continuous wear time for tight-fitting (unpowered) RPE is less than an hour, after which the wearer should take a break.’
Another challenge for employers is workers that have beards. Guidance from HSE recommends that those with facial hair, scars, wrinkles or marks which prevent a tight seal in the area use a loose-fitting device: ‘The wearer needs to be clean-shaven around the face seal to achieve an effective fit when using tight-fitting facepieces. Training is a good opportunity to make employees aware of this. If workers have beards, or are unable to be clean-shaven, a tight-fitting device will not be suitable so an appropriate loose-fitting device should be chosen.’
The HSE’s guidance – Is your mask protecting you? raises this important, point as having this knowledge will help provide them with better protection.
How to conduct face fit testing
You can use one of two face-fit testing methods – either quantitative or qualitative – but whichever one you choose, they need to be carried out with the same exercises and conditions and with a competent person doing the face fit test.
The key points are:
- No smoking, drinking, eating or chewing gum for 15 minutes before the test, as this could affect the results;
- No beards or stubble where the mask seals because this affects the fit (some goatee beards are ok but it depends where the mask sits. on the wearer; there may also be an issue with longer side burns);
- A test must be done for each different type of mask – so anyone wearing a dust mask and a half mask will need more than one test.
This quantitative test is a precise method that uses a device to count the particles in the air outside the mask and compare them to what is inside the mask.
The qualitative test uses the wearer’s sense of smell and taste to detect any leaks in the mask’s seal.
During the Face Fit Test a series of 60 second exercises are carried out to determine if the mask fits correctly in this order:
- Normal breathing;
- Heavy breathing – walking/stepping with the mask on;
- Turning head from side to side;
- Moving head up and down;
- Heavy breathing – walking/stepping with the mask on;
- Normal breathing.
How to fit your RPE
- Make sure you are clean-shaven around the face, to seal an effective fit;
- Make sure your hands are clean;
- Make sure that you read the manufacturer’s instructions for checking the respirator and putting it on correctly;
- Make sure it’s the right disposable respirator for you and that you have been fit tested for that respirator;
- Check the model and size of the mask and, if the respirator is folded open it out. Check the straps, the face seal and the nose clip. Check the filtering material for holes by putting it up to the light and looking through it, looking through the filter material;
- When checking during exhalation check the rubber diaphragm is present and can form a seal over the valve, it’s not damaged and that there are no foreign objects inside it. If the respirator is squashed, crumpled or damaged simply do not use it.
- When putting a respirator on make sure that it is the right way around. Cup the disposable respirator in one hand with the straps hanging out of the way. Hold the respirator in place on your face. Pull the bottom strap over your head to the back of your neck. Pull the top strap over your head to sit above your ears and over the crown of your head. Check the strap’s not twisted, if you need to tighten the straps pull both ends at the same time, bottom first then the top. Use a colleague or mirror to check the respirator and straps are in the right positions.
- Don’t over tighten the respirator, it should be tightly fitted but still comfortable. If you wear glasses make sure they do not create a gap between the respirator and your face.
- Before entering your workplace do a fit check to make sure you put your respirator on correctly and there is no leakage around your face;
- Make sure your hands are clean before you carry out that check;
- Cup your hands over the filter material without affecting the fit of the mask and breathe in. The respirator should suck down hard onto the face when you breathe in sharply. Breathe sharply out, you should not feel any leaks around the edges of the respirator. Repeat this until you feel you achieve a good fit.
HSE has produced guidance on how to train users sufficiently. An appropriate training programme could cover areas including why RPE is needed, how it works and how to wear and check the RPE correctly.
The final, important point, to remember is that there is a requirement (HSG 53) for an over 28-day mask maintenance record. The guidance states that thorough tests should be carried out at least once a month, or if the RPE is only used occasionally, the interval for testing shouldn’t exceed three months.
The guidance provides five key points that need to be followed when carrying out RPE maintenance:
- Follow the manufacturer’s instructions.
- A competent person should carry out the work.
- Keep records (see figure 7 for an example).
- Ensure the intervals for maintenance are appropriate.
- The maintenance programme should reflect the complexity of maintaining the RPE.
HSG 53 adds: “Ideally, any parts that require replacing will be sourced from the original manufacturer of the RPE. This will ensure any replacement parts continue to allow the equipment to operate as originally intended and perform to the standards that ensure the RPE offers the protection stated by the manufacturer.”
The guidance makes it clear that employers must keep records of examination and testing, and any repairs made, for at least five years.
Key maintenance tasks include:
- changing any replaceable filters;
- cleaning the device;
- valve maintenance and replacement;
- checking the straps for damage;
- checking the battery charge and flow rate for powered devices.