Technical Reports

Study of Fire Extinguishment of a Replacement Fluid for Use in Transformers in Lieu of Askarel

  • 01
  • Apr
  • 1982
AUTHOR: David B. Heard
SUBJECT: Evaluation
KEYWORDS: Midel, Transformer Fluid, Transformer Flammability
ABSTRACT: A series of tests were performed at the Factory Mutual Test Center 1) to obtain information on the performance of various extinguishing agents used with hand-held fire extinguishers to control fire involving a Midel, a transformer fluid for replacement of Askarel, and 2) to compare the results with those obtained in a previous test series involving two other replacement transformer fluids. The tests were designed to simulate the ignition and development of a pool fire which might follow accidental transformer case rupture. The extinguishing agents and dispensing hardware selected were those that might conceivably be carried on board vehicles or, in the case of water spray, might be available from local fire departments. Laboratory tests were performed on the Midel fluid to determine 1) flash and fire points, 2) time of piloted ignition, 3) pyrolysis rate, 4) convective and radiative heat release rates, and 5) gaseous product generation rates. Purple K dry powder appeared to be the best extinguishant for use on Midel spill fires. Of three Askarel replacement transformer fluids evaluated in this and the previous tests Midel appeared to bum the most violently.