Testing electric light bulbs. Endurance testing of electric light bulbs. Samples are taken from a production line and tested as part of a quality control procedure. These are filament light bulbs, which have a shorter lifetime than newer forms of lighting technology such as fluorescent lights. For electric filament bulbs, the lifetime depends greatly on the voltage used. Long-life bulbs are simply ordinary bulbs running on a lower voltage. Depending on the voltage used, lifetimes may range from as little as 2 hours to many years. Average values for normal operating conditions are around 1000 hours continuous use.