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  5. Mercury Vapor Lamps (Mercury Vapor Light Bulbs)
  1. Home, Business, and Entertainment Products

Mercury Vapor Lamps (Mercury Vapor Light Bulbs)


Mercury vapor lamps are bright, long-lasting light sources that are often used to light large areas such as streets, gyms, sports arenas, banks, or stores. The bulbs have an inner quartz tube containing the mercury vapor discharge. This is enclosed by an outer glass bulb that filters out harmful short-wavelength ultraviolet (UV) radiation.

There are two types of mercury vapor light bulbs sold in the U.S.

  • “T” type light bulbs have a self-extinguishing feature that shuts off the light within 15 minutes after the outer bulb is broken.
  • “R” type light bulbs do not have a self-extinguishing feature. They should only be installed in light fixtures that are fully enclosed by a lens of glass or plastic, or used only in areas where people will not be exposed to UV radiation if the outer bulb breaks.

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Under normal operating conditions mercury vapor lamps provide efficient, long-lasting sources of light. However, if the outer bulb breaks, and the inner tube continues to produce unshielded light, intense UV radiation is emitted. UV exposure at this level can cause eye and skin burns, blurred or double vision, headaches, and nausea.

It can be difficult to know if you are exposed to harmful levels of UV radiation exposure because the symptoms can take several hours to appear.

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Information for the Public

Ultraviolet radiation burns from high intensity mercury vapor light bulbs are a public health concern, especially in schools and other indoor facilities where the light bulbs may be subject to damage. The best way to reduce the risk of burns is to use fully-enclosed fixtures or self-extinguishing “T” type mercury vapor light bulbs in facilities where the public can be exposed to the UV radiation from a broken bulb.

For more information, see Ultraviolet Radiation Burns from High Intensity Metal Halide and Mercury Vapor Lighting Remain a Public Health Concern (December 6, 2005)

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Laws, Regulations & Standards

Manufacturers of electronic radiation emitting products sold in the United States are responsible for compliance with the Federal Food, Drug and Cosmetic Act (FFDCA), Chapter V, Subchapter C - Electronic Product Radiation Control.

Manufacturers of mercury vapor lamps are responsible for compliance with all applicable requirements of Title 21 Code of Federal Regulations (Subchapter J, Radiological Health) Parts 1000 through 1005:

1000 - General

1002 - Records and Reports

1003 - Notification of defects or failure to comply

1004 - Repurchase, repairs, or replacement of electronic products

1005 - Importation of electronic products

In addition, mercury vapor lamps must comply with radiation safety performance standards in Title 21 Code of Federal Regulations (Subchapter J, Radiological Health) Parts 1010 and 1040.30:

1010 - Performance standards for electronic products: general

1040.30 - High-intensity mercury vapor discharge lamps

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Required Reports for the Mercury Vapor Lamps Manufacturers or Industry

Industry Guidance - Documents of Interest

Other Resources

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