BOSTON — The number of on-duty firefighter deaths last year in the United States was the lowest in more than three decades.

In a report released today, the National Fire Protection Association said 72 firefighters died on-duty in 2010. That’s a sharp drop from the 105 on-duty deaths in 2008 and 82 in 2009. The group said it’s the lowest annual total since it began tracking it in 1977.

James Shannon, the association’s CEO and president, said advances in training, equipment and fire codes are major factors in reducing the number of deaths.