Using injury information from the 1986 Mine Safety and Health Administration database, and demographic information from a 1986 sample survey of the miner population, acute traumatic injury rates for male workers in underground bituminous coal mines were computed by age, current job experience, and total mine work experience. Three groups of workers assessed in this study showed the highest injury rates: workers aged 15-30 years; workers with between 2 and 3 years of experience; and workers with 10 or more years of experience in the current job. Injury rates decline with age in each time-interval of current job category and each total mine working experience category. Experience per se does not appear to be related to lower injury rates independent of age, which is paradoxical. The interaction of worker age with length of current or total mining experience is complex. The potential for catastrophic multiple fatalities and severe injuries suggests that additional work is needed to study, simultaneously, factors such as training and job task, and those that describe specific work exposures and mining hazards.