Less than 15 minutes. That’s how long the average person can remain conscious in freezing cold water. Death occurs around the 45-minute mark. Even when protected by a wetsuit, survival time for divers in the Arctic is measured in minutes, not hours, meaning researchers, rescue workers, and Navy SEALs — among the only people with reason to face the frigid depths — have to get in and out of the water as quickly as possible. There’s no room for lallygagging.
One simple way to boost the insulation of a wetsuit is to make it thicker (seals aren’t loaded with blubber for no reason). But increasing thickness comes at the cost of mobility — and for divers submerged under ice, mobility is key.
An innovative new technique could help make wetsuits more insulated. Developed by engineers at the Massachusetts Institute of Technology and described in a paper published this week in the journal RSC Advances, the method entails stuffing a standard wetsuit into a pressure tank that pumps it full of heavy inert gas. Once treatment is complete, this gas provides extra insulation and considerably increases the wetsuit’s protective capabilities and the length of time divers can survive in frigid waters.
“We have demonstrated a nearly twofold enhancement in the thermal insulation capabilities of a commercial wetsuit through a straightforward processing technique,” Anton Cottrill, an MIT graduate student who worked on the research, told Digital Trends.
To understand how the process works, it helps to know that neoprene — the standard material used to make today’s wetsuits — is riddled with air pockets. Some two-thirds of a wetsuit’s volume is actually air. By leaving a neoprene wetsuit in a pressure tank that’s filled with a gas like xenon or krypton, the gas is forced into the pockets of air, creating an extra bit of insulation and increasing the survivability of 14ºF water from less than an hour to up to three hours.
“A wetsuit is essentially a foam with bubbles of air trapped inside,” Cottrill said. “The air bubbles dispersed throughout the suit are the primary means of thermal insulation. So, the treatment works by placing the wetsuit into a container … that is pressurized with a gas … that is more thermally insulating than air. Through this high-pressure exposure, the gas infuses within the wetsuit and displaces the air. After removal from the chamber, the wetsuit is essentially filled with the highly thermally insulating gas.”
A wetsuit treated in this way for about a day can last for around 20 hours, according to the researchers. Moving forward, they want to decrease the rate at which the insulating gas leaks from the neoprene and hope to develop a technique that can “charge” a wetsuit indefinitely.