Dave’s worst nightmare became a reality when his house was tragically set ablaze by a discarded 9 volt battery. These batteries are normally found in smoke detectors, but can cause some serious damage. They’re dangerous because of how close the positive and negative posts are to each other. All it takes for disaster to strike is for the battery to touch a little bit of conductive metal.
This is quite an important lesson on the proper disposal of 9V batteries. These batteries easily short and have caused plenty of house fires in the past. Make sure to use electric tape to cover the terminals when you dispose of them. Be aware and be safe!