We test all of our styles each season for waterproofness. To measure waterproofness, we use a hydrostatic pressure measurement. This technique determines how much water pressure must be applied to a fabric before it begins to leak. A piece of fabric is stretched at the bottom of a long tube about 10cm in diameter. This tube is filled with water until the water comes through the fabric. When some water just begins to come through the fabric, one measures the height in millimeters of the water in the tube. This height is the water column and the fabric can withstand that measured pressure. With a water column of 3,000mm the fabric leaks when under pressure from 3 meters of water. The higher the water column the greater the protection against rain. A fabric is generally considered waterproof if the water column is 1,000mm or more. Below is an overview about waterproofing and its uses:
Water column - Weather conditions
1000mm to 3000mm - Resistant to light rain and moderate snow
3000mm to 5000mm - Resistant to moderate rain and snow
5000mm to 10,000mm - Resistant to long drives or hikes in heavy rain and wet snow
>10,000mm - Resistant to heavy rain and downpours, wet snow and high pressure
