What was found
PRESSURIZATION FAILURE ON DEPARTURE -AIR RETURN CABIN P. CLIMBED TO 10,000+ PUT ON OX MASKS (BOTH OF US) DESCENDED TO 10,00, CABIN KEPT CLIMBING, WAS IN RED. THEN DESCENDED SLOWLY BACK DOWN TO NORMAL LEVELS. C/A-R & R PNEUMATIC AND ELECTRO PNEUMATIC OUTFLOW VALVES IAW EMB-145 MM 21-31-04 AND EMB-145 MM 21-31-03. OPC GOOD. REF NRWC 909-ORD-05388.