As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DFW - CREW REPORTED DURING DESCENT BOTH PACKS FAILED. CREW DONNED MASKS AND CABIN O2 MASKS DEPLOYED. EMERGENCY DESCENT TO 10,000. EMERGENCY DECLARED LANDED DFW WITHOUT INCIDENT. AIRCRAFT REMOVED FROM SERVICE. REPLACED LEFT PILOT VALVE PRESS REGULAR LINE AND PILOT PSI REGULATOR VALVE LINE. SYSTEM GROUND CHECKED NORMAL OPERATION.