What was found
MAIN CABIN DOOR SEAL MAKING A STEADY HISSING NOISE FROM BOTTOM OF DOOR WHILE CLIMBING TO FL410. NO CAS OR PRESSURIZATION INDICATIONS ASSOCIATED. OPENED AND CLEANED THE DOOR SEAL MATING SURFACES USING ISOPROPYL ALCOHOL TO REMOVE GRIME, DEBRIS, AND DIRT. A VISUAL INSPECTION WAS PERFORMED AND THE SEAL WAS FOUND TO BE UNDAMAGED AT THIS TIME. WE PERFORM A PRESSURIZATION CHECK AND COULD DUPLICATE THE SQUEALING NOISE REPORTED IN FLIGHT. REF AMM 52-10-20,21-31-00.