B737-800
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
Human Factors; Aircraft
While configuring the aircraft for deicing in accordance with checklist; First Officer was attempting to turn off broadband switch in a dark; pre-dawn cockpit; and inadvertently deployed passenger oxygen masks.Turning off broadband switch is a relatively new procedure; and the switch is in close proximity to not only passenger oxygen switch; but flight recorder switch as well.Paying more attention prior to activating switch; but broadband switch could be moved to a less critical area on the overhead panel. When passenger oxygen masks were accidentally deployed; all passenger masks deployed. However; none of the forward galley masks deployed; and aft galley aircraft right masks failed to deploy.In an actual depressurization event; this could have been problematic for the flight attendants in their jumpseats unable to use the masks.
B737 Captain reported the First Officer inadvertently activated the wrong switch during de-icing procedures and deployed the oxygen masks.