- Author
- Fulcomer, P. M.
- Title
- Temperature Measurement on Operating Recessed Lighting Fixtures.
- Coporate
- National Bureau of Standards, Gaithersburg, MD
- Sponsor
- Consumer Product Safety Commission
- Report
- NBSIR 79-1913, September 1979, 22 p.
- Distribution
- AVAILABLE FROM National Technical Information Service (NTIS), Technology Administration, U.S. Department of Commerce, Springfield, VA 22161. Telephone: 1-800-553-6847 or 703-605-6000; Fax: 703-605-6900. Website: http://www.ntis.gov
- Keywords
- lighting equipment | temperature measurements | thermal insulation | thermocouples | lamps | wires
- Identifiers
- recessed incandescent lighting fixture; hazardous temperatures; protective barrier; branch circuit wiring; electrical junction box; load current
- Abstract
- Potentially hazardous temperatures may result from adding thermal insulation in the attic above recessed incandescent lighting fixtures. The National Electric Code for 1978 specifies that "...thermal insulation shall not be installed within three inches of a recessed fixture enclosure, wiring compartment or ballast and shall not be so installed above the fixture as to entrap heat and prevent the free circulation of air..." The purpose of this investigation was to determine the effectiveness of various protective barriers in maintaining the requisite three-inch spacing and in preventing over-temperature conditions when loose-fill insulation is installed around recessed lighting fixtures. For the devices tested, the results indicate that properly installed open-top barriers are sufficient to allow the fixture and associated branch circuit wiring to operate within specified ratings. However, a barrier closed at the top by any method, can cause branch circuit wiring, the external surface of the barrier and/or prts of the fixture to operate at temperatures above those designated as "safe".