This study investigates whether there is evidence of age related impairment in injury occurrence among assemblers in the Swedish automobile industry. A retrospective analysis of injuries sustained by male and female assemblers over a 10-year period (1980-1990) was conducted, employing five age categories divided into ten yearly strata and three time periods. Age-related injury ratios (IRs) were calculated for all injuries aggregated as well as for overexertions, falls and missteps, and injuries by contact. Contrary to expectation, IRs for older assemblers were generally low while consistently high IRs were recorded for younger assemblers, and for both male and female workers. The study offers no support for the likelihood of age-impairment among assembly workers of either gender. Inequalities in risk exposure and early deselection from the occupation are the most likely factors explaining these results.