This Smart Emergency Light performs as an ordinary light in normal times and it's able to sense if the power is caused by switch-off or power-off. While the power is off it'll provide more than 120 mins emergency lighting automatically. Moreover,there're also self-testing functions of the light including monthly self-testing and yearly self-testing. Since the light has the same appearance as normal downlight, it'll be a good improvement for public places lighting with fire fight requirement as well as household lighting.