Overhead fluorescent light fixtures are covered by a diffuser to reduce glare. This cover must be removed before you can change the bulb or install a new ballast. The most difficult part of removing a fluorescent light cover is simply reaching the fixture, especially if you are working in a commercial building with high ceilings. Use a sturdy ladder and have someone standing by to steady you if needed.
Place a ladder under the fluorescent light fixture. Do not position the ladder directly under the fixture, as this will make it difficult to work with your arms straight over your head. Instead, set the ladder a few inches away from one edge of the fixture.
Shut off the light fixture. You can also turn off the circuit breaker switch that controls the room to ensure that there is no electrical power to the light.
Look for a set of retaining clips or screws that hold the cover plate onto the rest of the light fixture. Release the clips or remove the screws, whichever is applicable to your light fixture. Slide the cover out.