In 50 Ways Firefighters Die Retired Deputy Chief FDNY Vincent Dunn lists timber trusses as a major cause of death among firefighters because of their weight and the fact that when they collapse, they often allow walls to fall as well.

Truss construction is a dangerous roof or floor design when exposed by fire. The large surface-to-mass
ratio of the truss and many small, interconnecting members makes it vulnerable to early collapse.
Wood truss roof collapses have killed 28 firefighters over the past three decades. Truss roofs kill
firefighters working below the truss, on top of the truss, and outside the truss roof building. When a
timber truss roof collapses, it can cause the collapse of an outside bearing wall.

28 firefighter deaths in the last 30 years are attributable to truss collapses. It seems to me this problem can be approached from at least two sides. First, designers might be able to consider fire retardant materials that will decrease the chances of truss failures due to fire. Second, if firefighters are somehow made aware that they will be working in or around a structure that has timber trusses, they may be able to avoid them in case they do fail. I have absolutely no idea how to deal with the the second approach. Posting signs with the design qualities of the burning building does not seem feasible and there is not time to look up the structural design elements of a building before running into it. Looks like this is might be a design issue.

This entry was posted on Thursday, February 28th, 2008 at 1:02 pm and is filed under Alternative Materials, Structural Components. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.