Mercury (Hg) occurs naturally in the environment and is commonly known as quicksilver. It is a heavy metal, like lead and cadmium. It is a poor conductor of heat. It is used in barometers, manometers, and thermometers and as a liquid contact material for electrical switches, fluorescent lamps, skin lightening products, pharmaceuticals, and it is used in certain electric batteries. Mercury metal and some mercury compounds are very toxic. People who work with mercury can experience health problem such as gum inflammation, loss of teeth, permanent nervous system damage, and kidney and muscle damage over a long period of time. People can be exposed to mercury through their diet (fish, shellfish), work (mining, production, transportation), human activity (coal- fired power stations, residential coal burning for heat and cooking, industrial processes, waste incinerators, and other metals mining), and through industrial processing. Health effects of mercury can be determined by the type, dose, age of the exposed person, duration, and the route of exposure (dermal, ingestion, or inhalation). The U.S. has a set of laws and regulations regarding the concentration of mercury in water, air, drugs, food, and soil by the EPA, FDA, and state/local authorities. OSHA’s Permissible Exposure Limit (PEL) for mercury is 0.1 milligrams per cubic meter over an 8 hour time-weighted-average, and NIOSH recommends an average of 0.05 milligram per cubic meter over a 10 hour workday. The OSHA respiratory protection program must be in place if respirators are in use. This includes a fit test, air measurements, and training for wearing a respirator, and it must be based on the hazard level. In addition, to minimize the risk of skin contact, required PPE should be used. In case of a spill employees must be trained for proper clean up with a mercury spill kit. Educating and training employees on mercury safety will help reduce or eliminate hazard exposure.


  1. Safe Work Practices Involving Mercury:
  • To prevent spill of mercury, dispose of any outdated glass containing mercury.
  • If it is possible replace mercury devices with other devices which can be used for the same purpose.
  • If possible, use clean energy sources instead of coal burning for power or heat. This will help to protect employees as well as the environment.
  • Be aware of any equipment containing mercury at your workplace.
  • Use adequate PPE when necessary.
  • Do not take mercury home on your clothing or skin.
    • Using disposable clothing or PPE will help prevent this.
  • Never eat or drink in an area exposed to mercury.
  • Spill Procedures:
    • Isolate contaminated area.
    • Use mercury spill kits for cleanup.
    • Spills must be carefully cleaned by a trained person. Untrained employees should never clean up mercury spills.
    • According to OSHA, employees selected for mercury spill cleanup must use proper PPE.
    • Use only disposable PPE for spill cleaning.
    • Spill area must be clearly labeled until proper cleanup is accomplished.
    • NIOSH recommends prompt cleaning of mercury spills with a vacuum cleaner and a water-soluble mercury decontaminant.
  • Medical and biological monitoring is required when working with mercury.
  • If a worker is exposed to mercury, emergency response is required.