Every so often, I'll come across a news story that includes statements from homebuilder's associations similar to this one, which was made during a recent report from a local ABC news affiliate: "The homes built today all have smoke detectors that are wired, and we have the national statistics that show that 99.4 percent of lives are saved because you're awake, you're woken up, you get out of the house."
The statistic, when used in this context, is misleading. There's no doubt that smoke alarms are necessary tools that can significantly reduce fire deaths and injuries. These devices, however, do nothing to extinguish a fire. The 99.4-percent figure estimates the likelihood of surviving a home fire when smoke alarms are present, which is not the same thing as reducing the risk of death.
Get all the facts by checking out the post on NFPA's Fire Sprinkler Initiative blog.