BS EN 343:2019
The latest version of EN 343 is BS EN 343:2019.
One of the main amendments of this 2019 update to EN 343 was the addition of class 4. Previously, EN 343 certified protective clothing was categorised between class 1-3. As such, the boundaries for class 2 and 3 shifted to account for the introduction of class 4.
In class 4, the waterproofness of the whole garment, including fabric and seams, offers the highest level of protection against rain and is tested after pre-treatment.
The EN 343 standard is currently under review. A further standard update, namely EN ISO/FDIS 24232:2023 - Protect clothing - Protection against rain, is under development.
EN 343 requirements and test methods
Protective clothing that is certified to EN 343 is classified based on two key requirements. Known as X and Y, these requirements are:
- Water penetration resistance (X)
- Breathability (Y)
The performance of rainproof protective clothing is then measured against these requirements. The results from the EN 343 tests conducted are used to determine the class level of protection offered, with class 4 representing the highest level of protection.
EN 343 certified protective clothing will be marked with a pictogram on the label. This pictogram will feature the European standard name (EN 343), as well as numbers and/or letters to specify the class level for both the X and Y categories.
Water penetration resistance (X)
The X category for EN 343 indicates the waterproofness, or water penetration resistance, of the protective garment.
EN 343 assesses the waterproofness of protective clothing by assessing the resistance to water penetration of the whole garment, including the fabric and seams. This water resistance test is conducted before pre-treatment and after pre-treatment for both the fabric and the seams.
These tests measure the waterproofness of clothing in pascal pressure units (Pa) whereby 1,000 Pa is equivalent to approximately 102 mm H20. Rainfall can be categorised as:
- 20,000 mm or higher - Extreme weather conditions
- 15,000 mm - Heavy rain for a long time
- 10,000 mm - Continuous rain for a long time
- 5,000 mm - Moderate rain for a long time
- 3,000 mm - Light to moderate rain for a shorter period of time
| Water penetration resistance (WP) | Class 1 | Class 2 | Class 3 | Class 4 |
| Fabric tested before pre-treatment | WP ≥ 8,000 Pa | — | — | — |
| Fabric tested after each pre-treatment | — | WP ≥ 8,000 Pa | WP ≥ 13,000 Pa | WP ≥ 20,000 Pa |
| Seames tested before pre-treatment | WP ≥ 8,000 Pa | WP ≥ 8,000 Pa | WP ≥ 13,000 Pa | — |
| Seames tested after pretreatment by cleaning | — | — | — | WP ≥ 20,000 Pa |
*Pa = Pascal Pressure Units
1,000 Pa is approximately 102 mmH2O |
Breathability (Y)
The Y category for EN 343 indicates the water vapour permeability, or breathability, of the protective garment.
To assess the breathability of the protective garment, a water vapour resistance test is conducted. This test measures breathability by assessing the Ret rating of the garment. The lower the Ret rating, the better the breathability:
- RET 0-6 - Extremely good or very good breathability
- RET 6-13 - Very good or good breathability
- RET 13-20 - Good or satisfactory breathability
- RET 20-30 - Unsatisfactory or limited breathability
- RET 30+ - Unsatisfactory or no breathability
When testing the water vapour resistance of the protective clothing, all layers of the garment in combination should be taken into consideration to determine the class level for breathability.
Protective clothing determined as class 4 should offer the highest level of breathability.
| Water vapour resistance (Ret) | Class 1 | Class 2 | Class 3 | Class 4 |
| Fabric tested before pre-treatment | Ret > 40 | 25 < Ret ≤ 40 | 15 < Ret ≤ 25 | Ret ≤ 15 |
Note: All classes can result in a restricted wearing time
