Determination of critical fallout condition of tempered glass in an enclosure fire

Publication date: Available online 17 August 2018

Source: Fire Safety Journal

Author(s): Yu Wang, David Rush

Abstract

Tempered glass is extensively used in modern high-rise buildings. However, in some instances the glass will break and fall out when subjected to a fire which will create a new ventilation condition, drastically changing the enclosure fire dynamics. In this work, eleven tempered glass panels with dimensions of 815 × 815 × 6 mm³ were heated by a pool fire placed in the center of a 1000 × 1000 × 1000 mm³ compartment. Parameters such as glass surface temperature, heat flux, failure time and fallout behavior, were all recorded. Weibull distributions were then employed to investigate the probabilistic characteristics of tempered glass fallout. Failure probability functions, survival probability functions, and probability density functions (derivative of failure probability function) of tempered glazing were obtained and compared with those of clear and coated glazing. The critical temperature difference and critical heat flux, with 5% failure possibility for 6 mm-thick tempered glazing, are 301 °C and 36.17 kW/m², respectively, which could be used as a conservative estimate for the safe design of glass façades in a fire.

https://ift.tt/2vT52oS