A multilayer tubular structure intended for the transportation of hydrogen, comprising, from the outside toward the inside, at least one barrier layer and at least one internal layer located below the barrier layer, said internal layer or the combination of the layers and of the other optional layers located below the barrier layer containing, on average, from 0% to 1.5% by weight of plasticizer, with respect respectively to the total weight of the composition of the layer or to the total weight of the combination of the compositions of the layers and of the other optional layers located below the barrier layer, said internal layer exhibiting a content of extractables, determined according to the standard CSA/ANSI CHMC 2:19, of less than or equal to 3% by weight of the sum of the constituents of said composition, said internal layer predominantly comprising at least one polyamide of aliphatic type or consisting of more than 75% of aliphatic units, said aliphatic polyamide being chosen from: a polyamide, denoted A, exhibiting a mean number of carbon atoms per nitrogen atom, denoted C A, of from 4 to 7; a polyamide, denoted B, and a mean number of carbon atoms per nitrogen atom, denoted C B, of from 7.5 to 9.5; a polyamide, denoted C, exhibiting a mean number of carbon atoms per nitrogen atom, denoted C C, of from 10 to 18; with the proviso that, when said internal layer comprises at least three polyamides, one at least of said polyamides A, B and C is excluded, at least one, more external, layer, located above the barrier layer, is present, said external layer predominantly comprising at least one polyamide of aliphatic type or consisting of more than 75% of aliphatic units, in particular the said aliphatic polyamide exhibiting a mean number of carbon atoms per nitrogen atom of from 9.5 to 18, advantageously from 11 to 18, at least one second external layer located above the barrier layer is present, and preferably located above the layer, said layer being plasticized, said plasticizer being in particular present in a proportion of from 1.5% to 15% by weight, with respect to the total weight of the composition of said layer; the thickness of said layer preferably represents up to 20% of the total thickness of the tubular structure, in particular up to 200 μm. said internal layer or the combination of the layers and of the other optional layers located below the barrier layer containing, on average, from 0% to 1.5% by weight of plasticizer, with respect respectively to the total weight of the composition of the layer or to the total weight of the combination of the compositions of the layers and of the other optional layers located below the barrier layer, said internal layer exhibiting a content of extractables, determined according to the standard CSA/ANSI CHMC 2:19, of less than or equal to 3% by weight of the sum of the constituents of said composition, said internal layer predominantly comprising at least one polyamide of aliphatic type or consisting of more than 75% of aliphatic units, said aliphatic polyamide being chosen from: a polyamide, denoted A, exhibiting a mean number of carbon atoms per nitrogen atom, denoted C A, of from 4 to 7; a polyamide, denoted B, and a mean number of carbon atoms per nitrogen atom, denoted C B, of from 7.5 to 9.5; a polyamide, denoted C, exhibiting a mean number of carbon atoms per nitrogen atom, denoted C C, of from 10 to 18; with the proviso that, when said internal layer comprises at least three polyamides, one at least of said polyamides A, B and C is excluded, at least one, more external, layer, located above the barrier layer, is present, said external layer predominantly comprising at least one polyamide of aliphatic type or consisting of more than 75% of aliphatic units, in particular the said aliphatic polyamide exhibiting a mean number of carbon atoms per nitrogen atom of from 9.5 to 18, advantageously from 11 to 18, at least one second external layer located above the barrier layer is present, and preferably located above the layer, said layer being plasticized, said plasticizer being in particular present in a proportion of from 1.5% to 15% by weight, with respect to the total weight of the composition of said layer; the thickness of said layer preferably represents up to 20% of the total thickness of the tubular structure, in particular up to 200 μm. a polyamide, denoted A, exhibiting a mean number of carbon atoms per nitrogen atom, denoted C A, of from 4 to 7; a polyamide, denoted B, and a mean number of carbon atoms per nitrogen atom, denoted C B, of from 7.5 to 9.5; a polyamide, denoted C, exhibiting a mean number of carbon atoms per nitrogen atom, denoted C C, of from 10 to 18; with the proviso that, when said internal layer comprises at least three polyamides, one at least of said polyamides A, B and C is excluded, at least one, more external, layer, located above the barrier layer, is present, said external layer predominantly comprising at least one polyamide of aliphatic type or consisting of more than 75% of aliphatic units, in particular the said aliphatic polyamide exhibiting a mean number of carbon atoms per nitrogen atom of from 9.5 to 18, advantageously from 11 to 18, at least one second external layer located above the barrier layer is present, and preferably located above the layer, said layer being plasticized, said plasticizer being in particular present in a proportion of from 1.5% to 15% by weight, with respect to the total weight of the composition of said layer; the thickness of said layer preferably represents up to 20% of the total thickness of the tubular structure, in particular up to 200 μm.