From The Ergoweb® Learning Center

Shaping Night Work for a Better Fit with Workers

Night work gambles with productivity and lives because it abuses the body clock, set for activity during the day and rest during the night. As the 24-hour-workplace is a fact of modern society, night work can’t be abolished. But maybe it can be tamed. New research by ergonomists and other specialists in workplace issues suggests ways to make it a smaller problem with the clever scheduling of shifts.


A study by Circadian Technologies reported in Business Week quantifies the harm. It concludes that obesity, diabetes and heart disorders are higher for night workers, that they have a 20 percent greater chance of being involved in a severe accident and make five times more serious mistakes than their daytime counterparts. Bill Davis, Vice-President of Operations at Circadian Technologies, explained for The Ergonomics ReportTM that the potential for ill effects is greatest between 3 and 5 am. “At that time, it is most difficult to maintain alertness,” he said. “It’s the period known as the circadian nadir.”    


Take rail transportation, for example
Shift work is a fact of life in railways. Irregular shifts often place bleary-eyed operators at the controls between 3 and 6 am, when experts say the body’s natural circadian rhythm produces maximum drowsiness. Frequent derailments, crashes and toxic spills from tankers tell the story of the consequences. During investigations, operators have likened the on-the-job fatigue to being in a constant state of jet lag. After one of several fatal rail crashes in the United States investigators described operators who were “drunk with exhaustion.”


An article published in the Chicago Tribune in May explores these US railway incidents, and suggests that they are not strictly a problem of shift work and poor scheduling

This article originally appeared in The Ergonomics Report™ on 2005-05-04.