Fluorescent fluctuations

If you step into any British classroom, chances are you will be greeted by the bright white light of fluorescent lamps. Schools began to introduce fluorescent lighting in the mid-1950s and rows of these low cost, long life, high efficacy lamps tend to be the lighting of choice in many schools around the world.

But some fluorescent lighting could actually be causing eye-strain and headaches. This is down to the fact that many fluorescent tubes (but not all) vary in colour and brightness continually. This is because the light of fluorescent bulbs is produced by a gas discharge (like lightning) twice with each cycle of the alternating current.