It's well known that environmental conditions, the combination of air temperature, airflow, and relative humidity determine the power of evaporative cooling. The hotter the day, the dryer the air, the greater the evaporative cooling effect.
On June 18, 2001, 3M's Safety and Security Systems Division published the results of a study performed by North Carolina State College of Textiles in Raleigh, NC, to determine the effectiveness of the same three-layer fabric that us used in the Silver Eagle Outfitters cooling apparel. The following are the results of that study: