You likely already know how to dispose of a burned out CFL light bulb, but what are you supposed to do if one breaks? The small amount of mercury contained in CFL light bulbs means it's important to handle a broken bulb with an eye toward staying safe.
The U.S. Environmental Protection Agency recommends that you have all people and pets leave the room if a CFL light bulb breaks. On your way out, air out the room by opening a window or door. Five to 10 minutes should be sufficient.
The EPA also encourages you to turn off any central air heating or cooling systems while you're airing out the room.
Since vacuuming could spread mercury-containing powder or vapor, you should instead scoop up any glass or powder using stiff paper or cardboard. Tape can also be used to pick up any tiny fragments or powder residue. Place these materials in a glass jar or plastic bag that can be sealed afterward. Then place these materials in an outside container.
Keep in mind that depending on where you live, disposal methods like this may be outlawed. You may have to take broken CFL bulbs to a local recycling center.
Either way, be sure to wash your hands carefully after disposing of the broken bulb.