Defining Waterproof

Every outdoor adventurer owns waterproof gear, yet few people fully understand it.
Part of that’s because there are no standards, and companies often use tests that favor their technology.

“There (are) different methods which can allow the fabric providers to make their product look better than another one just based on the numbers,” says Chad Kelly, eVent Fabric‘s global product manager. “This doesn’t actually mean it will be the most comfortable product out there, or the highest performing.”


And Jeff Dorton, The North Face‘s materials commercialization director agrees.
“If something makes their product look not so good, they tend to shy away from that test method even though it might be the best way to test it,” he says.

Still the Mullen Burst Test, and the ISO 811 test are two of the most common methods. Both measure the amount of pressure it takes for water to penetrate the fabric, but the Mullen measures the pressure in pounds per square inch while the ISO measures it in millimeters. A highly waterproof fabric withstands 20,000mm of pressure; some people say 10,000mm is the ski industry standard.

“10,000mm is really just a minimum for most people to believe it’s actually waterproof. In actuality, that’s a heck of a lot of water. There aren’t a lot of situations you can find yourself in where your raincoat will be subjected to those kind of conditions,” says Karen Beattie, Polartec‘s product marketing manager.

But the various situations create the need for a variety of products built for specific purposes. Having a jacket that keeps water out is one thing, but also making it breathable is another.
“Before Gore-Tex products were introduced over 30 years ago, the paradigm of being both waterproof and breathable was not possible,” says Tom Boyle, Gore‘s strategic marketing associate.

“In many cases you want that textile to breathe more because of the aerobic activity you’re doing,” The North Face’s Dorton says.
In these aerobic situations, a 10,000mm garment that’s breathable will keep you dryer than a 20,000mm garment that’s not.

But as confusing as the lingo can be, it’s up to retail employees to be able to decipher it-if they need to at all.
Bill Miller, owner of Hamilton Sports in Aspen, Colo., says his customers generally aren’t confused on the waterproof/breathable jargon. But he says that may be because most of his softgoods customers are buying Kjus and expect the product to perform.
“I don’t know how important (technical details are) to a lot of people,” he says.

And Heather Stanton, a buyer at Sturtevants Mountain Outfitters in Idaho, agrees.
“They usually know the name Gore-Tex and that’s probably the only name they know,” Stanton says.
Most customers walk into the store knowing they want something waterproof but look for employee advice to direct them.
Ultimately, customers want to go skiing, and if they like the jacket or pants and a salesperson says its good, then that’s all that matters, Stanton says.