Water column is a standard often used to express how waterproof a fabric is. The term is derived from an international test setup where the material is fastened at the end of a tube, which is then filled with water, creating a column of water. Generally, the higher the column before water leaks through the material, the more waterproof the material is.
Though standards vary depending on producer or brand, the material must be at least 3 000 mm to be considered waterproof. A Blæst product on the other hand, ranges from 8 000 mm to 20 000 mm, with several layers of taped sealed seams on the inside of the membrane, making sure water is never allowed to pass.
Blæst is rainwear for anywhere, so the only way for you to truly prove these numbers for yourself, is to wait for the rain, put on your Blæst and embrace the outdoors.