AbstractBackgroundIn 1999, the Occupational Safety and Health Administration (OSHA) proposed regulations designed to reduce work related inquiries by limiting worker exposure to “ergonomic risk factors.” Congress subsequently overturned the regulations. We provide additional evidence on earnings losses attributable to musculoskeletal disorders (MSDs), and thus on the need for an ergonomic standard.MethodsRegression techniques are used to analyze data from a survey of injured workers that has been matched to employer‐reported earnings data covering pre‐ and post‐injury periods, and to workers' compensation claims records.ResultsMSDs lead to large and persistent earnings losses. Cost estimates used by OSHA to justify the 1999 EPS are corroborated. Losses are greatest among workers who file workers compensation claims, but nonclaimants also have losses.ConclusionsEarnings losses and lost productivity associated with work‐related MSDs are substantial and an ergonomic standard could be cost effective. Am. J. Ind. Med. 45:329–337, 2004. © 2004 Wiley‐Liss, Inc.