EN 342 and EN 14058 are not the same thing
Both standards address cold conditions, but each covers a different task. EN 342 covers protection against cold, i.e. environments of approximately minus 5 °C and below, and applies to a set of clothing. EN 14058 covers cool environments above this threshold, as well as draughts and localised cooling, and applies to an individual item.
On the label they look similar, as the same cold pictogram is normally used for both. They are distinguished by the standard number below the pictogram, so this is the first thing to check upon receipt of the goods.
| EN 342 | EN 14058 | |
|---|---|---|
| What it covers | protection against cold, approximately minus 5 °C and lower | cool environments above approximately minus 5 °C, draughts, localised cooling |
| Subject of certification | a set (jacket and trousers together) or an item in a declared combination | an individual item: jacket, vest, trousers |
| Main measured value | Icler, actual thermal insulation of the set in m²·K/W | Rct, thermal resistance of the material, classes 1 to 4 |
| Basic label marking | Icler value with letter B or X and air permeability class | Rct class |
| Optional markings | Ret, water penetration resistance | thermal insulation, air permeability, Ret, water penetration resistance |
| Typical environment | cold stores and freezer facilities, long outdoor winter shifts | construction sites, logistics, unheated warehouses, transitional seasons |
What the numbers on the label mean
Icler (EN 342) is the actual thermal insulation of the complete garment set in m²·K/W, measured on a thermal manikin. The value is accompanied by a letter indicating which underwear was used during measurement: B denotes the reference underwear specified in the standard, while X denotes underwear that must be specifically stated. If the worker wears something different, the declared value no longer applies in full.
The figure itself does not indicate a temperature. The standard links it, via tables, to the activity level (from rest to moderate work, expressed as metabolic heat output in W/m²) and to the exposure time, usually eight hours and one hour. The same jacket will therefore withstand a lower temperature for a worker who is moving than for one standing at a loading ramp.
Rct (EN 14058) is the thermal resistance of the material, classified into four classes:
| Rct class | Value (m²·K/W) |
|---|---|
| 1 | from 0.06 to less than 0.12 |
| 2 | from 0.12 to less than 0.18 |
| 3 | from 0.18 to less than 0.25 |
| 4 | 0.25 and above |
Air permeability (AP) indicates how much air passes through the fabric. A lower value means better wind protection:
| AP class | Permeability |
|---|---|
| 1 | above 100 mm/s |
| 2 | above 5 up to and including 100 mm/s |
| 3 | up to and including 5 mm/s, the most windproof |
Optionally, Ret (resistance to water vapour transfer, three classes, with the highest class denoting the lowest resistance and thus the most breathable material) and resistance to water penetration (two classes, with the higher one requiring the requirement to still apply after the prescribed pre-treatment) may also be declared. A missing marking is not in itself a defect; it merely means that the property was not tested and declared. The meaning of individual abbreviations is compiled in the standards glossary.
Layering: three layers, each with one task
Heat is retained by still air trapped in the fibres and between layers, not by the fabric itself. That is why, for work with varying intensity, three thinner layers generally perform better than one thick jacket.
- Base layer: wicks moisture away from the skin. Merino or synthetic. Cotton retains moisture and cools you down once work stops, so it is not the right choice under a winter jacket.
- Mid layer, insulation: fleece or synthetic filling. Its job is to trap air, so it must be loose-fitting. This layer changes depending on the temperature, while the outer layer stays the same.
- Outer layer: stops wind and water. Here, the air permeability class and water column rating matter. The cut must be wide enough to close over the mid layer without straining.
For ordering, this means one specific thing: sizes are measured with the mid layer worn, not in a T-shirt. The items most commonly combined this way are collected in the winter range.
Why an overly thick jacket is counterproductive
- Sweat. During moderate physical work, the body releases moisture even at low temperatures. Wet insulation loses much of its effectiveness, and cooling occurs when work stops.
- Compression. Insulation compressed by a tool belt, strap or overly tight outer layer loses air and, with it, insulation. The same applies to footwear: a thick sock in the same shoe size provides less warmth than a thinner one in the correct size.
- Movement. Whatever hinders work is opened or removed by the worker. An open jacket does not protect according to any class.
Practical rule: choose insulation based on activity level and duration of exposure, not the lowest temperature of the year. For shifts that combine outdoor work with work in a vehicle or warehouse, two thinner layers are generally better than one thick jacket. The exact threshold is determined by the risk assessment for the specific workplace.
Water column: what the number tells you and what it doesn't
The water column is the pressure at which water penetrates fabric, measured according to EN ISO 811. It is quoted in two units, and this is where most misunderstandings arise.
- 1 mm of water column is approximately 9.81 Pa, so 1,000 mm is approximately 9.8 kPa.
- The threshold values in the rainwear protection standard EN 343 are expressed in pascals and start at 8,000 Pa for the lowest class, which is approximately 800 mm water column.
So when a quotation states "water column 10,000", do not compare this figure directly with the standard's requirement until you have aligned the units.
Three caveats not covered by the value alone:
- It is the fabric that is measured, not the finished product. Water penetrates through seams, zips and pockets sooner than through the material. For a rain garment, what matters is whether the seams are taped and how the openings are constructed.
- The value decreases over time. The surface water-repellent finish wears out through abrasion, dirt and washing. The fabric becomes damp, loses breathability and feels wet, even though the membrane beneath still holds. This is why standards also test after a prescribed pre-treatment.
- Point pressure exceeds the measured value. Kneeling, sitting on a wet surface, and backpack straps locally exceed the pressure applied in the laboratory test.
The final pitfall works the other way: a very high water column figure without a Ret value often indicates poor water vapour transmission. Moisture accumulating on the inside looks like leakage, but actually comes from the worker.
What to check before ordering
Winter orders most often fall down on details that can be checked in five minutes.
- The number under the pictogram. EN 342 or EN 14058, and whether the certificate applies to the set or to the individual item. A jacket certified as part of a set does not achieve the declared value when combined with arbitrary trousers.
- Match with the workplace. Compare the declared values with the activity level and exposure duration from the risk assessment, not with the coldest day of the year.
- Other requirements on the same item. A winter jacket for road or rail work must also comply with EN ISO 20471, and a rain jacket with EN 343. Combined markings are listed on the same label.
- Sizes and samples. Take measurements with the mid-layer worn, and before placing a large order, trial a sample item during a shift.
- Care instructions. The label states the number of cleaning cycles for which the properties remain valid. Washing at too high a temperature and the use of fabric softener reduce the effect of insulation and water-repellent treatment.
For comparing models based on this data, catalogues are available, and for assembling a specific set by size, an enquiry.
EN 342 and EN 14058 are not two classes of the same standard, but two answers to two different forms of cold. If you know the activity level, the duration of exposure and what is worn under the jacket before ordering, choosing the class is relatively straightforward. The numbers on the label confirm this decision, they do not replace it.