The policy should include the following the whole time that the person is away from home.

medical and health cover for an injury or sudden illness
24 hour emergency service and assistance
personal liability cover in case you cause injury or damage to property
lost and stolen possessions cover
cancellation and curtailment (cutting short the trip) cover
extra cover for activities that are commonly excluded from standard policies

The policy may also include:

personal accident cover
legal expenses cover
financial protection in case the airline goes bankrupt before or during the trip.