Warm workers work better, an ergonomics study at Cornell University finds.

Chilly workers not only make more errors but cooler temperatures could increase a worker's hourly labor cost by 10 percent, estimates Alan Hedge, professor of design and environmental analysis and director of Cornell's Human Factors and Ergonomics Laboratory.

When the office temperature in a month-long study increased from 68 to 77 degrees Fahrenheit, typing errors fell by 44 percent and typing output jumped 150 percent. Hedge's study was exploring the link between changes in the physical environment and work performance.

"The results of our study also suggest raising the temperature to a more comfortable thermal zone saves employers about $2 per worker, per hour," says Hedge, who presented his findings this summer at the 2004 Eastern Ergonomics Conference and Exposition in New York City.

In the study, which was conducted at Insurance Office of America's headquarters in Orlando, Fla., each of nine workstations was equipped with a miniature personal environment-sensor for sampling air temperature every 15 minutes. The researchers recorded the amount of time that employees keyboarded and the amount of time they spent making error corrections. Hedge used a new research approach employing software that can synchronize a specific indoor environmental variable, in this case temperature, with productivity.

"At 77 degrees Fahrenheit, the workers were keyboarding 100 percent of the time with a 10 percent error rate, but at 68 degrees, their keying rate went down to 54 percent of the time with a 25 percent error rate," Hedge says. "Temperature is certainly a key variable that can impact performance."

He will continue to study the impact of indoor environment on worker productivity. "Our ultimate goal is to have much smarter buildings and better environmental control systems in the workplace that will maximize worker comfort and thereby productivity," Hedge says.