Mercury thermometers, used in some science labs, require special safety precautions. Alcohol thermometers, though less dangerous, should still be handled carefully to avoid broken glass.
When inserting a thermometer into a rubber stopper, such as that on a distiller head, according to Seattle Central Community College, twist gently and press firmly, but don't use brute force. If necessary, use a drop of glycerine or other lubricant to make the thermometer slide more easily.
When performing this procedure, hold your hand less than 1 inch from the stopper to avoid exerting torque on the thermometer.
Lab thermometer safety depends on the type of thermometer: broken alcohol thermometers and other non-mercury thermometers only require the same cleanup as any other broken glass, according to University of Illinois at Chicago. A broken mercury thermometer requires special cleaning procedures.
High school and college students should never try to clean up a mercury spill from a broken mercury thermometer; instead, inform other students, turn off any heat sources, and tell an instructor. Trained department staff will come to clean up the spill.
Mercury Spill Cleanup
Personnel responsible for cleaning up a mercury spill, according to Princeton, should wear protective clothing, gloves and goggles, and use index cards to sweep the contaminated material into a sealable jar. Never use a vacuum cleaner or sink. Label the jar, and deliver it to a hazardous waste facility.