Wet Donning: Why It Matters

One of the most overlooked but vital aspects of immersion suit performance is its ability to maintain thermal protection during wet donning—when the suit is put on after the wearer is already wet, such as during a storm, abandon-ship scenario, or rescue operation.

In the extreme thermal test of the Arctic 25+ suit, the test subject's underclothing was deliberately soaked with 2.0–2.3 kg of water, simulating a worst-case wet donning scenario. Despite this, the suit maintained stable core and skin temperatures, with the Arctic 25+ model even showing a slight increase in core temperature after 3 hours. This demonstrates the suit’s exceptional insulation integrity, even when internal moisture is present.

By contrast, standard LSA-type neoprene suits—commonly used for regulatory compliance—are

highly vulnerable to water ingress. When wet donning occurs, water trapped between the skin and neoprene rapidly conducts heat away, accelerating hypothermia.

• Neoprene suits lose up to 40–45% of their thermal protection with just 1 liter of water

ingress [2].

• Skin temperatures can drop below safe thresholds within hours, often triggering test

termination due to discomfort or risk [2].

This vulnerability makes traditional neoprene suits unsuitable for Polar Code operations, where wet donning is not just possible—it’s likely.

The Arctic 25+ suit’s ability to maintain thermal protection even under extreme wetting

conditions sets a new benchmark for survival gear. It ensures that real-world performance matches

or exceeds test conditions, making it the only suit system currently validate