Summary
We propose to adopt a new airworthiness directive (AD) for certain Bombardier, Inc. Model CL-600-2B19 (Regional Jet Series 100 & 440) airplanes. This proposed AD was prompted by a report of a fire which started in the vicinity of an electrical panel that was fed by oxygen escaping from a damaged third crew person oxygen line that occurred while the airplane was on the ground. This proposed AD would require replacing and changing the routing of the flexible oxygen hose of the third crew person oxygen line and modifying the entrance compartment assembly. We are proposing this AD to prevent the possibility of damage to the third crew person oxygen line and an oxygen-fed fire in the airplane.