11:44 Feb 5 

From a "wellwisher":
It has to be simply "live loads" aka "imposed loads", these being quite simply the loads imposed when the building is in service, i.e. over and above dead load. The French have taken a "belt and braces" approach, adding the redundant "d'exploitation".*

And I think it is indeed "inférerieur" which is meant. Given that they refer to the "valeurs utilisées dans l’exploitation actuelle du bâtiment", I assume an analysis for a change in use of the building has found the new occupant's proposed imposed loads are systematically ("toujours") lower than those of the current occupant.

* POSSIBLE reason for the apparent redundancy, given that "charges d'exploitation" refs static (furniture, stores, etc.), dynamic (people, vehicles, etc.) and climatic (snow and wind) loads (cf. Dicobat). Unless climatic loading has potentially changed, the loads concerned relate only to active "operation" of the building. Dicobat defines "surcharges" as exceptional loads. but I've never encountered this. I DO know that "surcharge" is used synonymously with "charges d'exploitation": the "sur-" part refers to the fact that these loads are "over and above" the dead loads of the building.