Many interior and exterior surface-mount fluorescent light fixtures have acrylic or wire grill covers that you remove when changing the lamps or cleaning the covers. Most recessed fixtures have flat or convex decorative covers that you push up to remove. Typically, acrylic covers for surface-mount fixtures fit at the outer edge of the fixture. Wire grill covers -- also known as wire guards -- are held in place with small fasteners. Removing a cover from an installed fluorescent light requires the ability to work on a ladder.
Clear the area of the floor below the light fixture whose cover you want to remove. Place a stepladder to access the light fixture.
Grip the upper lip of an acrylic cover at one side of the fixture with your fingers. Pull outward on the lip to disengage it from the side of the fixture. Lower that side of the cover and lift out the opposite side from the opposite side of the fixture. Proceed to the following steps to remove a wire guard cover.
Work from the stepladder. Locate small pan-head screws or hex-head screws that secure clamps to the body of the fixture at the outer edge of the cover.
Loosen and remove pan-head screws, using the appropriate screwdriver. You can use a nut driver to remove hex-head screws.
Hold the cover in place with one hand. Disengage the clamps from the body of the fixture and remove the cover. If necessary, rotate the clamps to disengage them from the fixture.