Most people know that we are 'falling back' this weekend in much of the US and saying goodbye to Daylight Savings Time. Because you should change the batteries to your smoke alarm twice a year at a minimum, this is a perfect time to remember to do that. They recommend you check the alarm is sounding monthly, but the batteries should be tossed after 6 months just to be safe.
Did you know that smoke alarms expire? They are only designed to last 7-10 years. While you have the smoke alarm down, also check the date. When you press the button and it sounds the alarm that only indicates it's getting power not that the sensor is functioning properly. If there is a date printed on the back that is the MADE ON date...replace if it was 10 or more years ago. If there is only a printed serial number and no date, it is pre-1999 and needs replaced.
We replaced ours this morning. Here in the US, basic units at Home Depot run less than $10. We went with a carbon monoxide sensor/smoke detector alarm combo and those started at $30. It's important that you have at least one on each level of your home and if you have a spread out floor plan on the level where your bedrooms are, it is a good idea to have one outside of each section that has a bedroom.
Stay Safe :)