Failure Analysis of a Carbon Dioxide Fire Extinguisher

Fire extinguishers are a familiar sight on domestic and commercial premises, and although their presence usually goes unnoticed, they can literally be a lifesaver when the need arises. There are several different kinds of extinguisher, and in the case of the carbon dioxide type, they are charged to extremely high pressure and therefore contain a vast amount of stored energy. As such, the consequences of failure can be very serious. In this study, a situation is described where poor servicing practice meant that, rather than improving the safety of factory workers, the extinguishers themselves posed a serious threat to their wellbeing. The extinguishers were, in effect, time bombs in disguise. Following an explosion of one of the extinguishers, the owner took the responsible approach of commissioning a metallurgical investigation, which prevented further and potentially more serious incidents.