Changing the batteries in a smoke detector or alarm simply involves removing the face plate or entire unit from the mounting bracket, living the tab to remove the battery and inserting a new battery. Ensure your smoke detectors are working properly with help from a certified firefighter in this free video on home safety. Expert: Joe Bruni Bio: Captain Joe Bruni has more than three decades of experience as a street firefighter and company officer Filmmaker: Christopher Rokosz Series Description: Protecting your house and loved ones from disaster starts with implementing basic home safety precautions, such as installing smoke alarms, using a carbon monoxide detector, and having fire extinguishers on hand. Find more ways to protect your home with help from a certified firefighter in this free video series on home safety.