Methods
We reviewed summaries provided by the Federal Emergency Management Agency
of the deaths of all on-duty firefighters between 1994 and 2004, except for deaths
associated with the September 11, 2001, terrorist attacks. Estimates of the proportions
of time spent by firefighters each year performing various duties were obtained
from a municipal fire department, from 17 large metropolitan fire departments, and
from a national database. Odds ratios and 95% confidence intervals for death from
coronary heart disease during specific duties were calculated from the ratios of the
observed odds to the expected odds, with nonemergency duties as the reference category