 Special hoods are applied here to provide suction on the top side of a test assembly in order to reach the 50Pa pressure differential.Afterwards, a 30PSI hose-stream test may be applied.Outdoor spray fireproofing methods that must be qualified to the hydrocarbon curve may be required to pass a host of environmental tests before any burn takes place, to minimize the likelihood that ordinary operational environments cannot render a vital system component useless before it ever encounters a fire.