The MEDIF (Medical information Form THAI 1225) is required in all cases as specified in the PHM 2.3.3. It is a standard form recommended by IATA for the medical clearance and handling of sick/invalid passengers who need to travel by air. The instructions given on the form are to be allowed by cabin crew. Authorization of transportation (Acceptance Authorization Form THAI 1223) for sick/invalid passengers is prepared by sales office.