The state fire marshal is urging Iowans to change the time, AND the batteries in smoke detectors this weekend. As Americans “fall back” to push their clocks back an hour to regular time, fire officials use the occasion to remind folks to change the batteries in their smoke detectors, too.State Fire Marshall George Howe estimates up to 75 percent of the fire deaths in Iowa could have been prevented if there had been a working smoke detector in the home. He says it’s important to have a smoke detector in every level of your house. He says the earlier the warning, the better in allowing you to survive a fire.Howe has over half a dozen smoke detectors in his own home. When he moved into the house, there were three “hard-wired” smoke detectors powered by electricity. He added battery-powered detectors so they’ll work even if the power’s off.