European Standard · Respiratory Protection
EN 140 – Half Masks and Quarter Masks: Requirements for Reusable Respirators
EN 140 is the European standard specifying requirements for half masks and quarter masks designed to be used with separately certified replaceable filters, offering a reusable alternative to disposable filtering facepieces for respiratory protection.
1. Scope
EN 140 covers reusable half masks (covering nose, mouth and chin) and quarter masks (covering nose and mouth only) that connect to replaceable particle, gas or combined filters. It specifies requirements for materials, fit, valve performance, and connection standards for filters.
2. Exclusions & Related Standards
- Does not cover disposable filtering half masks with no replaceable filter – see EN 149.
- Does not cover full face masks – see EN 136.
- Filters used with EN 140 masks must separately meet EN 143 (particle filters) or relevant gas filter standards.
- Frequently paired with eye protection meeting EN 166 for combined dust and splash hazards.
3. Key Requirements & Marking
Masks must meet requirements for facepiece materials, harness strength, exhalation valve performance, and standardised filter connections (thread or bayonet fittings) so that certified filters from compatible manufacturers can be attached securely.
4. Testing Overview
Testing covers leak tightness, breathing resistance with and without filters attached, valve housing durability, headharness strength, and practical performance assessments on wearers performing typical work movements.
5. Selection Guide
Half masks and quarter masks are chosen when workers need a durable, reusable facepiece that can be fitted with different filter types depending on the hazard of the day, making them more economical than disposables for daily, prolonged use across varied tasks.
6. Inspection, Care and Maintenance
- Clean and disinfect the facepiece after each use following the manufacturer instructions
- Inspect the silicone or rubber seal regularly for cracking, hardening or deformation
- Replace filters according to manufacturer service life or when breathing resistance increases noticeably
- Store the mask in a sealed container away from dust and direct sunlight between uses
- Carry out a fit test whenever switching to a new mask model or size
7. Frequently Asked Questions
What is the difference between a half mask and a quarter mask?
A half mask covers the nose, mouth and chin, providing a larger sealing surface, while a quarter mask covers only the nose and mouth, offering a lighter but sometimes less secure fit.
Can EN 140 masks be used with gas filters?
Yes, provided the connected filter is separately certified for the specific gas or vapour hazard and is compatible with the mask’s standardised connector.
How long can a half mask be used before replacement?
The facepiece itself can often be used for one to several years with proper care, while filters need replacing much more frequently according to manufacturer guidance or when breathing becomes difficult.
Is fit testing required for EN 140 masks?
Yes, fit testing is strongly recommended and often legally required to confirm the mask forms an effective seal on each individual wearer’s face.
Can beards affect the performance of EN 140 masks?
Yes, facial hair along the sealing area significantly reduces the effectiveness of the seal and is generally not permitted for tight-fitting respirator use.