This guide provides guidance to technical committees when they prepare or revise specification of environmental conditions to which reference is made in the rating requirements of equipment standards. It refers to equipment rating only with regard to operational performance, including transportation and storage of equipment. It is intended to be used as a basis for the coordination of IEC standards for equipment, in order to avoid unnecessary divergences. Independent of the coordinated specification of environmental conditions, for some equipment with particular characteristics, or for use under extreme conditions, some deviating values may have to be specified in the relevant IEC standard. The guide has been prepared with particular reference to electronic equipment but applies also to all other types of electrical equipment. This guide does not apply to equipment for exclusive use on ships and vehicles and in mines. Environmental testing in general, including climatic and mechanical testing as dealt with by IEC technical committee 50 and electrical testing as dealt with by IEC technical committee 77, is not within the scope of this guide. NOTES 1 The term "conditions" means a combination of the various parameters and their severity values. 2 In this guide the term "technical committees" covers both technical committees and subcommittees.