GUIDE TO RESPIRATORY PROTECTION
EN 149 AND RELATED STANDARDS
Respiratory Protective Equipment (RPE) is designed to protect the wearer from breathing in hazardous substances such as dust, mists, vapours, gases, or fumes. In some environments, RPE also supplies clean air where oxygen levels are insufficient.
In the UK, RPE must meet European standards that define the level of protection, the type of hazard, and the testing methods. Selecting the right protection requires a risk assessment of both the hazard and the working conditions.
1 — Identify the Task, the Hazard and the Risk of Exposure
- Task — What work are you doing? Cutting concrete, spraying paint, handling chemicals, or working in confined spaces?
- Hazard — Dust, vapour, gas, mist, fume, or oxygen deficiency.
- Risk — How frequent and long is the exposure? How severe are the health effects?
2 — Main Respiratory Protection Standards
EN 149:2001 + A1:2009 — Filtering Half Masks (FFP1, FFP2, FFP3)
This standard covers disposable filtering half masks (often called “disposable respirators” or “dust masks”). They are classified by efficiency:
| Class | Max Total Inward Leakage | Protection Factor | Typical Use |
|---|---|---|---|
| FFP1 | 22% | 4 x Workplace Exposure Limit (WEL) | Low-level dusts (sanding, DIY, light construction) |
| FFP2 | 8% | 10 x WEL | Moderate dusts, mists, welding fumes |
| FFP3 | 2% | 20 x WEL | Hazardous fine dusts, asbestos, biological agents, viruses |
EN 136 — Full Face Masks
This standard applies to full-face reusable masks made from durable materials.
- Provide a high level of protection against gases, vapours, and particulates (depending on filter used).
- Face seal and visor protect eyes as well as respiratory system.
- Often used in environments with toxic chemicals or high dust concentrations.
- Compatible with EN 143/EN 14387 filters.
EN 140 — Half Masks
This standard covers reusable half masks (covering nose, mouth, and chin, but not eyes).
- Designed for use with replaceable filters (EN 143, EN 14387).
- Lighter and less restrictive than full face masks.
- Used in moderate hazard environments where eye protection isn’t required.
- Requires regular cleaning and filter replacement.
EN 143 — Particulate Filters
This standard applies to replaceable particulate filters used with half masks (EN 140) and full face masks (EN 136).
Filters are divided into three classes:
| Class | Efficiency | Protection Factor | Examples of Use |
|---|---|---|---|
| P1 | 80% | 4 x WEL | Non-toxic dusts |
| P2 | 94% | 10 x WEL | Moderate dusts, mists |
| P3 | 99.95% | 20 x WEL | Highly toxic dusts, asbestos, radioactive particles |
EN 14387 — Gas and Vapour Filters
This standard defines filters for gases and vapours, including combined filters (gas + particulate). Each type is colour coded for quick identification.
| Filter Code | Colour | Protection | Examples of Use |
|---|---|---|---|
| A | Brown | Organic vapours (boiling point >65°C) | Solvents, paints |
| B | Grey | Inorganic gases/vapours | Chlorine, hydrogen sulphide |
| E | Yellow | Acid gases | Sulphur dioxide, HCl |
| K | Green | Ammonia and derivatives | Agriculture, fertiliser plants |
| AX | Brown (with marking) | Organic gases/vapours <65°C BP | Specific low-boiling solvents |
| Combined | Multiple bands | Mixed hazards | Spray painting, chemical handling |
3 — Key Considerations
- Fit testing: A tight seal is essential — HSE requires face-fit testing.
- Filter life: Particulate filters clog over time; gas filters become saturated and must be replaced before breakthrough.
- Environment: High humidity, heat, or confined spaces affect performance.
- Other PPE: Ensure compatibility with goggles, helmets, and ear protection.
4 — Special Hazards
- Asbestos — FFP3 or P3 filters minimum, often full-face.
- Biological agents — High-efficiency filtration (FFP3, P3).
- Oxygen-deficient atmospheres — Only breathing apparatus (BA) is suitable.
- Chemical spills — Gas/vapour filters or supplied air systems depending on substance.
Respiratory protection must always be selected based on a risk assessment and in line with UK HSE regulations. If you are unsure, speak to a safety officer or consult our team for advice.
