What was found
WHILE IN CRUISE FLIGHT CREW RECEIVED A BLEED 1 LEAK MESSAGE, FOLLOWED BY A BLEED 1 FAIL MESSAGE. CREW FOLLOWED QRH & MSG DID NOT RESET. CREW ALSO RECEIVED CABIN ALTITUDE HIGH WARNING MSG, CREW PROCEEDED WITH EMERGENCY DESCENT TO 10,000 FT AND DIVERTED. FLT DID DECLARE AN EMERGENCY INBOUND, CFR DID MEET THE FLIGHT ON ARRIVAL. CABIN O2 MASKS DID NOT DEPLOY BUT CREW DONED O2 MASKS. THERE WERE NO CUSTOMER INJURIES. WILL SWAP EQUIPMENT AND CONTINUE LATE. NR 1 ENG PERCOOLER FWD AND AFT GASKET HAS MISSING MATERIAL. INSTALLED GASKETS, FWD & AFT IAW AMM 36-11-08. NO LEAKS NOTED. OK FOR SERVICE.