Reference to IEC 60533 is made in IMO Resolution A.813(19) , and it assists in meeting requirements stated in SOLAS 74 (Chapter IV, Regulation 6 and Chapter V, Regulation 17).
Official copies of the IEC 60533:2015 (the current third edition) are available for purchase in PDF format through authorized distributors: iec 60533 pdf
for a certain equipment type, or do you need help comparing IEC 60533 with the standard for navigation equipment? IEC 60533:2015 - iTeh Standards Reference to IEC 60533 is made in IMO Resolution A