Hazards arising from external effects
This section has no associated Explanatory Memorandum
21.—(1) Equipment and protective systems shall be so designed and constructed as to be capable of performing their intended function in full safety, even in changing environmental conditions and in the presence of extraneous voltages, humidity, vibrations, contamination and other external effects, taking into account the limits of the operating conditions established by the manufacturer.
(2) Equipment parts used shall be appropriate to the intended mechanical and thermal stresses and capable of withstanding attack by existing or foreseeable aggressive substances.