This FireAngel smoke alarm conforms to the latest British Standards. It features optical smoke sensing technology, ideal for detecting slow smouldering fires and is resistant to nuisance alarms. This unit comes with a replaceable 1-year battery. It is recommended to contact your local fire prevention officer for advice or consult the Government website for specific legislation requirements, especially for homes in Scotland which now mandate ceiling-mounted and interlinked fire alarms. For smoke alarms that fully comply with new Scottish legislation, please see codes 98385, 54804, and 79890. This alarm cannot be connected to other alarms in your home.