Article D2223-116 of the French General Code of Local Authorities
Every vehicle used for transporting a body after coffining has a burial compartment designed to accommodate one or more coffins, separated in a watertight manner from the part of the passenger compartment reserved for the driver and passengers. The burial compartment may consist of a rigid, closed, watertight box that is immovable in relation to the body of the vehicle, completely covering the coffin.