Dangerous Goods by Road
thermal insulation, the thermal insulation systems shall satisfy the following requirements:
(a) it shall consist of a shield covering not less than the upper third but not more than the upper
half of the surface of the shell and separated from the shell by an air space about 40 mm across;
(b) it shall consist of a complete cladding of adequate thickness of insulating materials protected
so as to prevent the ingress of moisture and damage under normal conditions of carriage and so
as to provide a thermal conductance of not more than 0.67 (w.m-2.k-1);
(c) when the protective covering is so closed as to be gas-tight, a device shall be provided to
prevent any dangerous pressure from developing in the insulating layer in the event of
inadequate gas tightness of the shell or of its items of equipment; and
1 for calculation purposes g = 9.81 m/s2.
(d) the thermal insulation shall not inhibit access to the fittings and discharge devices.