Narrative:

[The] flight attendant in [the] lower lobe crew rest attempted to adjust reading light over her bunk during her break. [She] observed a 'puff' of smoke from bulb. She unilaterally elected to discharge a single shot of halon fire extinguisher on light fixture; then notified cockpit. [The] captain advised her to turn off [the] light; [but] she said she was unable to do so. [There was] no more smoke. No alarm activated in lower lobe crew rest or cockpit. Purser was advised and she investigated and reported to cockpit that problem was resolved. Lower lobe crew rest lights [were] turned off with switch in aft galley. All flight attendant crew departed [the] lower lobe crew rest as [a] precaution due to halon discharge. Captain called dispatch/maintenance. Maintenance recommended removing bulb from fixture. [That was] accomplished [with] no problem. Maintenance entered [a] write-up regarding [the] reading light and also [the] discharge of halon extinguisher. Maintenance and dispatch concurred with captain that continuation to the planned destination was prudent. Flight attendants monitored [the] lower lobe crew rest periodically for remainder of flight [with] no problems reported. Contract mechanics [were] debriefed on arrival. [The] mechanics inspected; [but] found no problems. [They] felt [that the] small amount of smoke was probably caused by faulty bulb.

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Original NASA ASRS Text

Title: The reading light in a B777's lower level crew rest area emitted a puff of smoke which a Flight Attendant then shot with halon. No fire or smoke sensors were activated.

Narrative: [The] Flight Attendant in [the] lower lobe crew rest attempted to adjust reading light over her bunk during her break. [She] observed a 'puff' of smoke from bulb. She unilaterally elected to discharge a single shot of halon fire extinguisher on light fixture; then notified cockpit. [The] Captain advised her to turn off [the] light; [but] she said she was unable to do so. [There was] no more smoke. No alarm activated in lower lobe crew rest or cockpit. Purser was advised and she investigated and reported to cockpit that problem was resolved. Lower lobe crew rest lights [were] turned off with switch in aft galley. All flight attendant crew departed [the] lower lobe crew rest as [a] precaution due to halon discharge. Captain called Dispatch/Maintenance. Maintenance recommended removing bulb from fixture. [That was] accomplished [with] no problem. Maintenance entered [a] write-up regarding [the] reading light and also [the] discharge of halon extinguisher. Maintenance and Dispatch concurred with Captain that continuation to the planned destination was prudent. Flight attendants monitored [the] lower lobe crew rest periodically for remainder of flight [with] no problems reported. Contract mechanics [were] debriefed on arrival. [The] mechanics inspected; [but] found no problems. [They] felt [that the] small amount of smoke was probably caused by faulty bulb.

Data retrieved from NASA's ASRS site as of April 2012 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.