An experimental study of forced ventilation glovebox fires

Abstract

An experimental study was performed to investigate the integrity of gloveboxes when subjected to lathe drip pan fires. These fires are potentially dangerous since glovebox failure may allow hazardous gases to escape containment. A full scale mockup of a glovebox and corresponding air flow system was constructed. Careful consideration was given to the two components expected to cause glovebox failure: the gloves and windows. In addition to normal tests, tests which introduced added ventilation openings (i.e. missing gloves, missing window) were also performed.

The glovebox ventilation system places these fires in the category of overhead forced ventilation compartment fires. Since little data has been obtained previously for this type of fire, further experiments were conducted to determine the effect of fuel surface area on fire behavior. In the past, these fires have been successfully modelled as well-stirred reactors.

Results showed that overall containment was achieved under normal glovebox conditions. Added ventilation opening tests, however, showed that these scenarios would lead to a loss of containment. Nevertheless, under no conditions did a catastrophic glovebox failure occur. Furthermore, experiments with reduced fuel surface areas showed that the fires became less hazardous as the pan diameter decreased. Exhaust gas concentrations, temperature data, burn rates, smoke generation, and heat releases were the criteria used to form this conclusion. Neither a well-stirred or two-layer environment was observed.