Smoke alarms need to be regularly checked or replaced.
Every month: smoke alarm should be tested every month, just press the "test"(detection) button to ensure that the battery is powered and the alarm can work properly.
Every six months: the smoke alarm should be cleaned with a vacuum cleaner to remove smoke and particles to prevent the alarm from working unproperly.
Every year: if the smoke alarm uses a 9-volt ordinary (lead or rust) battery, the battery should be changed every year. In order to remember to change the battery, a good way is to do it together every summer to the clock. If the lithium battery is built into the alarm can not be replaced, should be connected to the alarm every 10 years.
Every ten years: no matter which alarm，it should be replaced at least every 10 years, because the function will gradually decrease with the passage of time.
