A waterproof garment has received a DWR treatment which is a fluorocarbon-free treatment that makes the water pearl on the surface of the material. The membrane on the inside of the outer fabric is laminated and all seams are sealed with waterproof tape on the inside of the garment so that no water can penetrate. How waterproof a material is, is expressed in water columns which describe the water pressure in millimeters the material can handle before water seeps through the material. Imagine that you place a glass tube on a garment and fill with water.Once you have filled the tube up to 15,000 mm, ie 15 meters, then the water starts passing through the material. That means the garment has a water column of 15,000 mm. Waterproof materials are also rated on "breathability", which is the material's ability to release body moisture. m2 / 24h, ie how many grams of liquid the material can transport out, relative to a square meter, in a day.
A water-repellent garment is not entirely waterproof but can withstand light rain showers. It has received a fluorocarbon-free DWR treatment, which means that the water pearls and drains off. If the garment is exposed to rain for a prolonged period time, however, water will penetrate the material. The advantage of a water-repellent garment over a waterproof one is that it ventilates extremely well in comparison.