Background Data indicates that Denmark has relatively high risks of occupational injuries. We evaluated all injuries resulting in hospitalization by occupation. Methods All gainfully employed men younger than 60 in 1990 were divided into 47 industrial groups and followed using the National Inpatient Registry, for hospitalized injuries 1991-1993. Following ICD-8, injuries were grouped into six categories: head, upper extremities, back, trunk, lower extremities and ruptures, sprains and strains. Standardized industrial hospitalization ratios (SHRs) were calculated and Pearson's independence test was performed for each category. Results Industrial differences were ascertained for each injury category. The highest associated injury category was upper extremity injuries ranging from SHR = 43 (fire services and salvage corps) to SHR = 209 (slaughterhouse industry). Carpentry, joinery, bricklaying and construction work had significantly high SHRs for all injury categories, whereas administrative work was significantly low throughout. Conclusions Occupational surveillance systems based on hospitalized injuries can be used to identify high-risk industries, and thereby suggest where to direct prevention efforts. Am. J. Ind. Med. 38:619-627, 2000. (C) 2000 Wiley-Liss, Inc.