SUPPRESSION OF CLASS-A FIRES WITH HFC-227EA

lHFC-227ea (CF3CHFCF3;1, 1, 2, 2, 3, 3, 3-heptafluoro-propane) is an e ffective replacement for Halon 1301 in pre suppression systems, provid ing rapid extinguishment of flames through a combination of physical a nd chemical mechanisms. The vast majority of applications for HFC-227e a involve the protection of Class A hazards, which are characterized b y low fuel loadings and low energy output, with fire sizes often in th e range of 5-10 kW. Mid- and large-scale testing has demonstrated that HFC-227ea, at its minimum design concentration of 7.0% v/v, is effect ive at extinguishing fires typical of those expected to occur in elect ronic data processing (EDP) facilities, telecommunication facilities a nd anechoic chambers. The levels of HF produced following extinguishme nt of typical Class A fires with HFC-227ea were well below the estimat ed mammalian LC50 and the human Dangerous Toxic Load (DTL), and do not appear to present a threat to electronic equipment.