IEC 61892-2 contains provisions for system design of electrical installations in mobile and fixed units used in the offshore petroleum industry for drilling, production, processing and for storage purposes, including pipeline, pumping or 'pigging' stations, compressor stations and exposed location single buoy moorings. It applies to all installations, whether permanent, temporary, transportable or hand-held, to a.c. installations up to and including 35 000 V and d.c. installations up to and including 1 500 V. (a.c. and d.c. voltages are nominal values). This standard does not apply either to fixed equipment used for medical purposes or to the electrical installations of tankers. This edition includes the following significant technical changes with respect to the previous edition: - the d.c. voltage given in clause 1 has been updated to 1 500 V, to ensure consistency through all parts of the IEC 61892 series; - Clause 4 has been rewritten, such that all requirements to emergency power are now given in 4.3; - the tables for nominal a.c. voltages have been updated in accordance with the last revision of IEC 60038; - the requirement to cross sectional area for earthing conductors has been made dependent on the system earthing arrangement; - requirement for emergency stop for motor-driven fuel-oil transfer and fuel-oil pressure pumps has been added.