According to Clauses 17 and 18 of the Warsaw Convention, airline companies are liable for any damage that occurs to passengers or their belongings during in-flight. However, airline companies will not be held responsible if the damage results from the passenger's own fault or one of their temporary servants such as doctors assisting ill passengers on their own initiative (Clause 20). To be covered by air carriers, doctors should respond to the captain's call when it comes to assisting ill passengers. In such cases, doctors are considered an airline's temporary servants who acted on the airline's instructions. Major airlines are all covered by insurance to meet such contingencies and to cover doctors who act as their temporary agents.