If there was a fuel or oil fire, I know which I'd prefer to have. Hit the red button from a safe distance or go in to an enclosed space with a hose?
Foam inlets are common on oil tank storage rooms, oil boiler installations, ships, etc., for this reason. You can get lost and ashyxiate under the foam blanket, apparently, since it excludes the oxygen so effectively. This makes me to suspect that the test didn't go entirely to plan, since there were people in the hangar.