A lab in Münster measured 5.8 °C cooler skin

Anyone can make a claim. We wanted ours measured, by an independent institute. So Liquid Ice went to Dermatest GmbH in Münster, a dermatological testing institute, for a “test of tolerance and efficacy”.

How it was measured

20 volunteers, twelve women and eight men aged 22 to 60. The test area was the inner left forearm, measured without contact using an infrared instrument: once before, then after 5, 10, 20, 30, 60, 90 and 120 minutes, always on the same marked spot. On it went a bandage soaked in Liquid Ice. Before the test, average skin temperature was 31.6 °C.

The result

The measurement showed skin 5.8 °C cooler, averaged across all 20 volunteers. And after two hours, at the last reading, it was still cooling.

The report’s conclusion, translated from German: over 120 minutes it found “a clear and continuous cooling effect”. There were no unwanted skin reactions. Two specialists in dermatology signed the report.

Why evaporation cools

A liquid needs energy to evaporate. It takes that energy as heat from whatever it sits on, here the fabric and the skin underneath. Sweat works the same way, only slower. Liquid Ice contains alcohol as well as water, so it evaporates faster than water alone. It needs no freezer, and there is no ice-cold shock on the skin.

What a thermal camera shows

Long before Münster, Liquid Ice had been in front of thermal cameras: live on BBC One in 2002, and in 2005 in a series we commissioned with an infrared camera, ankle, knee, wrist and elbow, each filmed after 20 minutes under the soaked bandage. The pictures show where the cold sits: under the fabric. The number comes from Münster, measured the scientific way.

What that means for you

The lab measured the soaked bandage, meaning fabric well soaked in Liquid Ice lying on the skin. That is exactly how we recommend it: Liquid Ice belongs on fabric, not spread over bare skin. On fabric it evaporates more slowly and cools for longer; on bare skin it is gone in seconds.

What was not measured matters just as much. The measurement ended at 120 minutes, and we claim nothing beyond that. And what was measured is the temperature of the skin surface, nothing else.

A quick spritz on a dry shirt is therefore not the same thing as the measurement, and you get closest to the lab whenever the fabric is visibly damp and sitting snugly on the skin. Or take a bandage straight away: the Self Cooling Bandage to soak yourself, or the pre-soaked Active Ice Bandage. For shirts and bands there is the 500 ml bottle.

And if anyone asks where the 5.8 comes from: Münster, from 20 forearms.