The next time that the lights go out they may just glow. A company has created lights that are able to glow blue-green once the power is cut. Originally designed for the U.S. navy, the lights can be repurposed for any building.
This means that during a fire or some other mishap people will still be able to find their way out of buildings. If the light tubes break they will still glow – so they can be carried around – and what’s more is that the glowing is bright enough most people’s eyes need not adjust.