A method for the detection of leaks in a line system for fluid transportation, with a feed line and at least one venting outlet and one supply outlet, wherein • a first valve with a pilot leak is arranged in the feed line, which is a limiter connected in parallel to the first valve, • a second valve with a series-connected limiter is arranged in the venting outlet to the environment, and • a measuring device for determining the pressure difference is connected in parallel to the first valve, characterised in that the following steps are executed: a) lowering a second pressure in the supply outlet or in the venting outlet upstream of the second valve essentially to an ambient pressure by opening the second valve; and b) determining a maximum differential pressure of the fluid by means of the measuring device between a first pressure in the feed line and the second pressure if the second pressure is equal to the ambient pressure; c) calculating a maximum volume current of the pilot leak as the leak rate of the first valve; d) continually determining the differential pressure between the first pressure in the feed line and the second pressure in the supply outlet and calculating the actual volume current, wherein - an actual volume current calculated from the differential pressure, the value of which corresponds approximately to the maximum volume pressure as per step (b), points to a by now inadmissible leak in the supply outlet, and - an actual volume current calculated from the differential pressure, the value of which is smaller than 100 % and larger than 0 % of the maximum volume current as per step b), points to essentially no leak in the supply outlet. • a first valve with a pilot leak is arranged in the feed line, which is a limiter connected in parallel to the first valve, • a second valve with a series-connected limiter is arranged in the venting outlet to the environment, and • a measuring device for determining the pressure difference is connected in parallel to the first valve, a) lowering a second pressure in the supply outlet or in the venting outlet upstream of the second valve essentially to an ambient pressure by opening the second valve; and b) determining a maximum differential pressure of the fluid by means of the measuring device between a first pressure in the feed line and the second pressure if the second pressure is equal to the ambient pressure; c) calculating a maximum volume current of the pilot leak as the leak rate of the first valve; d) continually determining the differential pressure between the first pressure in the feed line and the second pressure in the supply outlet and calculating the actual volume current, wherein - an actual volume current calculated from the differential pressure, the value of which corresponds approximately to the maximum volume pressure as per step (b), points to a by now inadmissible leak in the supply outlet, and - an actual volume current calculated from the differential pressure, the value of which is smaller than 100 % and larger than 0 % of the maximum volume current as per step b), points to essentially no leak in the supply outlet. - an actual volume current calculated from the differential pressure, the value of which corresponds approximately to the maximum volume pressure as per step (b), points to a by now inadmissible leak in the supply outlet, and - an actual volume current calculated from the differential pressure, the value of which is smaller than 100 % and larger than 0 % of the maximum volume current as per step b), points to essentially no leak in the supply outlet.