Studies on fire and toxicity potential of bromo-butyl rubber of respiratory mask in a simulated closed environment

Abstract

This study aimed at evaluation of emission and fire characteristics of bromo-butyl rubber in closed and cone calorimetric conditions. Time to ignition was 30 s in cone calorimeter combustion, and flame out occurred at 315 s. Peak heat release rate (806.34 kW/m²) occurred at 68 s. CO and CO₂ started to build up at 40 s. In closed environment, peak pressure build up was gradually raising from the negative pressure (-200 mbar) conditions, to highest positive pressure conditions (400 mbar). Temperature rise observed to be 10.5-21°C. Peak CO emissions ranged from 34-55 ppm in case of positive pressure experiments. In TGA study, <i style="">T</i>_max was 440°C where 73% weight loss observed. Major observed emissions of bromo-butyl rubber were water vapour, CO, NO, CH₄ and CO₂. Risk hazard of bromo-butyl rubber based on flashover propensity, was high risk (<i style="">x</i> = 26.87) and based on total heat release was intermediate risk (<i style="">y</i> = 77.9) category. Computed toxicity index was very low in open controlled environment (0.02) and closed environment (0.06-0.18) conditions.