Discharge Characteristics of the International Space Station (ISS) Portable Fire Extinguisher (PFE) and the Effect on Closed Volumes

The Portable Fire Extinguisher (PFE) is used to displace oxygen and cool a closed volume to prevent/eliminate a fire hazard on the International Space Station (ISS). An analysis and test was performed on the discharge characteristics of the PFE system on a payload rack volume. Analytical data was developed to support the test data and determine the real versus ideal gas state of the carbon dioxide (CO₂) during discharge into the rack.

This paper presents the analytical and test data for PFE discharge to determine applicability of this system to rack and open volume fires with respect to mass discharged, local area concentration, temperature, and displacement volume. Ancillary to this analysis is a consideration of the local open volume carbon dioxide concentration and the probable impact on the crew and atmosphere revitalization and supply system for ISS. This report will include testing data recently performed at Marshall Space Flight Center (MSFC). The data from the simulation tool Generalized Fluid Flow Simulation Program (GFSSP) is included.