- Author
- Nowlen, S. P.
- Title
- Investigation of the Effects of Thermal Aging on the Fire Damageability of Electric Cables. Technical Report.
- Coporate
- Sandia National Labs., Albuquerque, NM
- Sponsor
- Nuclear Regulatory Commission, Washington, DC
- Report
- SAND 90-0696, May 1991, 90 p.
- Distribution
- Available from National Technical Information Service
- Contract
- FIN-A-1833
- Keywords
- electrical cables | nuclear power plants | fire safety | aging (materials)
- Identifiers
- cable damageability; nuclear power plant aging
- Abstract
- This report documents the findings of an experimental investigation of the effects of thermal aging on the fire damageability of electric cables. Two popular types of nuclear qualified cables were evaluated. For each cable type, both unaged (i.e., new off the reel) and thermally aged samples were exposed to steady-state elevated temperature environments until conductor-to-conductor electrical shorting was observed. Plots of the time to electrical failure versus the exposure temperature were developed and thermal damage thresholds were determined. For one cable type, the thermally aged cables were less vulnerable to thermal damage than were the unaged samples as demonstrated by an increase in the thermal damage threshold for the aged samples, and an extended survival time at exposure temperature above the damage threshold for aged samples compared to unaged samples. For the second cable, the threshold of thermal damage was lowered somewhat by the aging process, an indication of an increased vulnerabilty to thermal damage due to aging. However, for the higher temperature exposures, no statistical difference between the damage times for aged and unaged cable samples was noted. For both cable types, the changes in the thrmal damage threshold observed were not considered significant in terms of fire risk.