This European standard relates to protective clothing for rain, wind and cold in temperatures higher than -5°C. This standard specifies the requirements and testing methods applied to materials and seams of protective clothing with regard to bad weather conditions (for instance: rain or snow, fog and damp) IMPERMEABILITY This factor is fundamental for superior protection. The rainwear’s impermeability is determined by the garment’s material. In the symbol, impermeability is indicated on the location of the X with a number between 1 and 3, where the number represents the class. Impermeability is measured by the water pressure of a water column with a determined height and a determined diameter. The height of the column determines the class.
|1||Water column of at least 80 cm height|
|2||Water column of 80 cm to 130 cm height|
|3||Water column of at least 130 cm height|
The classic unit (g/m² per 24 hours) was easy to understand. However, the EN 343 uses a value of evaporative resistance (m². Pa/W), which is measured by the so-called ‘skin model’ (skin test EN11092). Important information for a better understanding: The higher the RET value, the stronger the vapour resistance of the material; consequently, less vapour passes in case of a high RET value. The laboratory performs this static test at 35°C. Breathable clothing removes the perspiration from the skin and the garment. If too much moisture accumulates in the garment, the condensation creates the impression of moist skin. In cold conditions the wearer runs the risk of cooling off quickly; in warm conditions the heart rate increases and there is a possibility of the development of thermal stress. A person feels well when the amount of perspiration produced by the body is equivalent to the amount of perspiration that is eliminated.
|1||RET-value higher than 40|
|2||2 RET-value between 20 and 40|
|3||RET-value lower than 20|