EN 140 sets the requirements for reusable half masks. The facepiece covers the nose, mouth and chin, and takes replaceable filters — particle (EN 143), gas (EN 14387) or combined.
Advantages over a disposable respirator
- One facepiece for many hazards — the filter is chosen to suit the task.
- A better and more repeatable seal, usually with several sizes available.
- More economical over time where exposure is regular.
- Can be cleaned, disinfected and repaired with spare parts.
Total inward leakage
Total inward leakage for an EN 140 mask must not exceed 2%, equivalent to FFP3. The overall protection factor also depends on the filter: a half mask with a P3 filter typically gives 20× protection.
Maintenance matters: valves, straps and seals are consumable parts. The mask should be inspected before every use and stored in a closed, clean container.