BRANZFIRE: Smoke Detector and Sprinkler Activation Times with Liquid Pool Fires

Abstract

BRANZFIRE is used to model the fire dynamics of liquid pool (pan) fires in a single room, and determine the activation time for smoke detectors located on the ceiling at various locations (every half meter) to the side of the fire. The activation time is also calculated for heat detectors and sprinklers at the same locations, and is also presented, using standard default values for the response time index RTI, C-factor, and actuation temperature. The BRANZFIRE code is an efficient zone type computer fire modeling software used to simulate fires in multi room structures. Its name is an abbreviation for Building Research Association of New Zealand FIRE model. This modeling software calculates various important things as a specified but constrained fire progresses, like the upper layer and lower layer temperatures and thicknesses, and optical smoke density. The time to activation of a smoke detector, heat detector or sprinkler is also calculated, and how this is affected by position and activation parameters may be determined. The software has got a wide variety of predefined fires and many other fires in their fire database (University of Canterbury, New Zealand online database). BRANZFIRE under predicts the activation times of smoke detectors but over predicts the activation times of sprinklers, as stated in the validation provided by the computer code developers. It is applied here to the calculation of smoke detector and sprinkler response time calculation with a variety of liquid pool (pan) fires in a single room, with closed door, and the fire located midway along one of the walls.