The human body cools itself by evaporation. Sweat reaching the skin absorbs heat as it turns to vapor and carries that heat away. It's efficient and it's automatic.

The catch is that it only works if the sweat actually evaporates. Sweat that pools on skin or soaks into fabric removes almost no heat — the body loses the water and gets none of the cooling. So it sweats more. Fluid loss climbs, fatigue sets in, and core temperature keeps rising.

Two things stop evaporation: still air and saturated fabric. A work shirt on a windless day produces both.

ZIPPKOOL doesn't add cold. It removes the obstacle — a continuous stream of air along the skin so sweat evaporates the moment it appears. The body's own mechanism, running at full capacity instead of half.

Two consequences worth stating:

• It cools the worker, not the space. No site cooling infrastructure required.
• Because sweat isn't wasted, the body produces only what it needs — less fluid loss, less fatigue.

In sustained high humidity, phase-change cooling may outperform evaporative. In extreme dry heat above roughly body temperature, airflow alone does less. Neither replaces hydration, rest, shade, and acclimatization.