Narrative:

During preflight the upper deck cargo fire suppression activated. After upper deck cargo deck door was opened; it was not possible keep halon from entering the forward vestibule area. To keep the crew from getting sick from breathing halon; at my insistence; I escorted the forward crew off of the aircraft while passengers were still on board the back part of the aircraft. This was a combi. No passengers were affected.

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Original NASA ASRS Text

Title: Test button activated the upper cargo deck Halon fire suppression system during preflight for a Combi modified aircraft; Crew evacuated the aircraft.

Narrative: During preflight the upper deck cargo fire suppression activated. After upper deck cargo deck door was opened; it was not possible keep Halon from entering the forward vestibule area. To keep the crew from getting sick from breathing Halon; at my insistence; I escorted the forward crew off of the aircraft while passengers were still on board the back part of the aircraft. This was a Combi. No passengers were affected.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.