Last Revised: April 22, 2020
Are you using mercury thermometers in incubators, water baths or other applications where a non-mercury thermometer would work just as well? Although mercury thermometers are not harmful when used properly, they pose a threat to human health and the environment when broken or disposed of as trash. The breakage of mercury thermometers is one of the most common accidents in research labs. When mercury thermometers break, drops of the liquid metal become lodged in floor cracks and behind equipment. Depending on the amount spilled and air movement within the lab, the mercury vapor concentration in a lab with "hidden" mercury spills may exceed safe limits. A spill is more dangerous when mercury thermometers break in ovens or in incubators because mercury evaporates readily at high temperatures, creating high mercury concentrations.
Alternatives
There are alternatives to the use of the mercury thermometers that are just as effective and affordable. The University chemistry stockroom, along with Fisher-Scientific "safety" thermometers that are usually filled with red mineral spirits or alcohol. The cleanup of a broken thermometer containing this material is decidedly easier and safer. Microprocessor-digital readout thermometers are also available.
Free Exchange
EHRS has an ongoing mercury thermometer exchange program. The program is designed to collect and replace -- for free -- potentially hazardous mercury thermometers with environmentally friendly ones. EHRS can exchange Total Immersion thermometers (-20° to 110° C and -20 to 150° C). To request these thermometers, please fill out this Non Mercury Thermometer request form.
What to do if You Break a Thermometer
Isolate the immediate area. Mercury can be easily tracked throughout a lab by people walking on the spill. Laboratory staff can safely clean up small spills such as those from a thermometer. Avoid exposure and injury by wearing nitrile gloves (mercury is absorbed through the skin), a lab coat, and safety glasses. Use tongs or other tools to pick up glass from the broken thermometer. Mercury droplets can be swept into a container with an index card. Carefully inspect the bench top and floors where the thermometer was broken to ensure that all the mercury is cleaned up. Mercury breaks into very small droplets that are difficult to see when spilled and can spread over a large area.
Package the spilled mercury and broken thermometer and contaminated objects in a sealable plastic container. Label the container with a Chemical Waste Label. Call EHRS at 215-898-4453 for disposal.
Contact EHRS for cleanup assistance for large spills such as those from a manometer or if a spill has contaminated surrounding equipment.
Cost of Mercury Spills and Disposal
Mercury waste is very expensive for disposal. Spill debris uses much more space than an intact thermometer. Currently, one 55 gallon drum of mercury waste shipped for disposal costs the University $1,500! Save the University's money by utilizing non-mercury thermometers.
Effects of Mercury
Mercury accumulates in the environment and pollutes air and water, causing a myriad of problems.