JAR-OPS 1.255 Fuel Policy:

(i) For A to A Flights - An operator shall specify the minimum fuel contents at which a flight must end. This minimum, final reserve, fuel must not be less than the amount needed to fly for a period of 45 minutes.

(ii) For A to B Flights – An operator shall ensure that the pre-flight calculation of usable fuel required for a flight includes:

(A) Taxi fuel - Fuel consumed before take-off, if significant; and

(B) Trip fuel (Fuel to reach the destination); and

(C) Reserve fuel -
(1) Contingency fuel - Fuel that is not less than 5% of the planned trip fuel or, in the event of in-flight replanning, 5% of the trip fuel for the remainder of the flight; and
(2) Final reserve fuel - Fuel to fly for an additional period of 45 minutes (piston engines) or 30 minutes (turbine engines); and

(D) Alternate fuel - Fuel to reach the destination alternate via the destination, if a destination alternate is required

(E) Extra fuel – Fuel that the commander may require in addition to that required under subparagraphs (A)