Falcon 900
Flight Crew Air Transport Pilot (ATP); Flight Crew Flight Instructor; Flight Crew Instrument; Flight Crew Multiengine
Flight Crew Last 90 Days 50; Flight Crew Total 3300; Flight Crew Type 500
Aircraft Equipment Problem Less Severe; Flight Deck / Cabin / Aircraft Event Other / Unknown
Flight Crew Diverted; General Maintenance Action
Aircraft
Climbing somewhere in the FL300s. Everything was fine; but it was noticeable something was questionable with pressurization. The cabin altitude warning light lit up and immediately initiated an emergency descent. We put our oxygen masks on; selected mask button on radio panel; and put 7700 in transponder as we started down on emergency descent. ATC tried contacting us on numerous occasions; and I tried responding to ATC when they would call. After getting to an altitude where we weren't in danger with mask; we went to hand mike to answer ATC calls. During the descent; there were no other aircraft involved; diversions from us or any other aircraft. I was the PNF and not able to communicate with ATC while mask was on; so PF had to communicate with ATC. We diverted by request due to availability of a maintenance facility. We were able to get pressurization system and mask button on PNF side checked out. Mask button was no good; the reason for no communication from me to ATC but no joy on pressurization system. We then took a tech rep for a test flight and wasn't able to recreate the earlier emergency. We are getting a new controller put in and a new mask button. I also called FSS to get a number for ATC for a telephone number so I could write a report. ATC told FSS to get my phone number in case they need to speak with us. We did not declare an emergency and was able to descend with no problems. Hopefully the new pressurization controller will fix any potential pressurization problems.
Falcon 900 crew initiated an emergency descent due to loss of pressurization. The Captain's oxygen mask microphone is inoperative.