Disposable dust masks look almost identical from a distance, and the difference between an FFP1 and an FFP3 is easy to miss when a box is being grabbed off a shelf. But the rating decides how much airborne dust the mask is designed to stop, and choosing the wrong one for the task is one of the more common PPE mistakes we see. This guide explains the ratings so you can read a box with confidence.
What FFP stands for
FFP means Filtering Facepiece Particle. It is the classification used in the European standard EN 149, which covers disposable half-mask respirators that filter particles such as dust, mist and fume. A mask marked EN 149 has been tested against that standard, and the number after FFP tells you which of the three classes it met.
FFP masks filter particles only. They do not protect against gases or vapours, which need a different type of respirator with the appropriate filter cartridge.
The three classes
| Class | Minimum filter efficiency under EN 149 | Typical use |
|---|---|---|
| FFP1 | 80% | Low-level, non-toxic dusts such as some hand sanding and general nuisance dust |
| FFP2 | 94% | Moderate-level dusts and mists, including many construction and woodworking tasks |
| FFP3 | 99% | Higher-hazard fine dusts such as silica, and tasks where the highest disposable-mask protection is needed |
The filter efficiency figures are the minimum performance the mask has to achieve in the standard test. The class also sets limits on how much air can leak in around the edges of the mask, which is where fit becomes critical.
Why face fit matters as much as the rating
An FFP3 mask that does not seal to the face is not giving FFP3 protection. Air takes the path of least resistance, and if there is a gap at the nose bridge or under the chin, unfiltered air comes in around the filter rather than through it. This is why UK guidance requires face-fit testing for tight-fitting respiratory protective equipment, including disposable FFP masks, and why the test has to be repeated if the wearer changes mask model or size.
Facial hair in the seal area prevents a proper fit. If someone cannot be clean-shaven where the mask seals, a different type of respiratory protection is needed rather than a higher-rated disposable mask.
Valved or unvalved
Many FFP masks have an exhalation valve, which lets breath out more easily and reduces heat and moisture build-up inside the mask. The valve does not change the filtering class, but it does mean the wearer's exhaled breath is not filtered. That matters in some environments, such as clean rooms or food production, where unvalved masks may be required.
Markings to look for on the mask
- EN 149:2001+A1:2009 or a later version of the standard.
- FFP1, FFP2 or FFP3 to show the class.
- NR or R: NR means non-reusable, for a single shift only; R means it can be reused subject to the manufacturer's instructions.
- D: the mask passed an optional dolomite dust clogging test, which indicates it should breathe more easily over a longer shift in dusty conditions.
- CE or UKCA mark with the notified body number.
Storage, issue and replacement
Disposable masks lose their shape and seal if they are crushed in a van door pocket or a coat. Keep them in the original box until issued, and replace a mask when it becomes hard to breathe through, gets damaged or wet, or at the end of the shift for NR-marked masks. See our guide to organising workwear and PPE storage for practical ways to keep PPE in usable condition on site.
The short version
FFP1, FFP2 and FFP3 are three classes under EN 149, in rising order of filtering performance. Choose the class based on your own risk assessment of the task, make sure every wearer has been face-fit tested on the exact mask they use, and store and replace masks properly so the rating on the box is the protection people actually get. For the wider picture on reading PPE markings, see our EN standards on workwear labels explained and eye and ear protection standards guides.
