# Ekvivalent luftlagstykkelse

> measure of a material's resistance to water vapor diffusion compared to that of a stagnant layer of air, calculated as the water vapor permeability of air divided by the water vapor permeability of the material in question

**Wikidata**: [Q17769414](https://www.wikidata.org/wiki/Q17769414)  
**Source**: https://4ort.xyz/entity/q17769414