A fabric's ability to prevent water penetration. Waterproofness is measured in Schmerber (pressure exerted by a water column). Clothing that has a value of 10,000 mm, can withstand 10 m of water. The greater the number, the more waterproof the fabric.
Breathability
A fabric's ability to wick away water vapour. 30,000 = extremely breathable clothing 20,000 = clothing with very good breathability 10,000 = breathable clothing 5,000 = clothing with low breathability