The 'Royal Naval Minewatching Service' ('RNMWS') was a civilian organisation formed in
1952 as part of the auxiliary forces of the
British Naval Service.
Its intended wartime role was to man observation points overlooking ports and strategic waterways, in order to report
mines dropped by aircraft.
In 1962, it was transformed into the
Royal Naval Auxiliary Service, intended as a short-notice response force to help disperse shipping in British ports in case of a nuclear strike.
References
★ ''Whitaker's Almanack: for the year 1958'', p. 470. J. Whitaker & Sons, London, 1957