Translation of "onerous" into French

As process workers they were trained for specific operations that were often dangerous and onerous.

On les formait pour effectuer des opérations spécifiques souvent dangereuses et pénibles.

She would be glad to obtain details of the school timetables, which seemed very onerous.

Elle souhaite obtenir des précisions sur les horaires scolaires, qui semblent très lourds.

The financial costs of treating injuries from some conventional weapons, such as landmines, are onerous.

Les frais de traitement des blessures causées par certaines armes classiques, comme les mines terrestres, sont onéreux.