What was found
ON DECENT THRU FL110, DIRTY SOCK & STINKY PAINT SMELL REPORTED IN FLT DECK AND CABIN. FLT CREW DECLARED AN EMERGENCY AND DONNED O2 MASKS. P-TRAK SNIFFER SHOWED PARTICLE SPIKE ON BOTH PACKS USING APU BLEED. APU PLACED ON MEL. PERFORMED ECS LEVEL B DECONTAMINATION. NO FURTHER ODOR NOTED AND P-TRAK READINGS GOOD. LATER, PERF APU COMPARTMENT & APU INSPECTION USING UV LIGHT. FOUND NO TRACE OF OIL CONTAMINATION IN COMPRESSOR, INTAKE OR EXTERNAL LEAKS. RAN APU & PACKS IN ALL MODES & N0 ODOR PRESANT. (LP 8537562, 8537568 - AIRCRAFT WAS GROUNDED)