1.1 This part of IEC 60079 contains the specific requirements for construction and assessment of intrinsically safe electrical systems, type of protection "i", intended for use, as a whole or in part, in explosive atmospheres in Group II locations. This document is intended for use by the designer of the system who may be a manufacturer, a specialist consultant or a member of the end users staff. 1.2 This standard supplements IEC60079-11 the requirements of which apply to electrical apparatus used in intrinsically safe electrical systems. 1.3 The installation requirements of a Group II system designed in accordance with this standard are specified in IEC 60079-14.