# The Merchant Shipping (Navigational Equipment) Regulations 1993, Regulation 27: Display sizes


A radar installation required to be provided which is or was installed onboard a ship on or after 1st September 1984 shall provide a relative plan display having an effective diameter, without external magnification, of not less than:
(a) 180 millimetres on ships of 500 tons or over but less than 1600 tons;
(b) 250 millimetres on ships of 1600 tons or over but less than 10,000 tons;
(c) 340 millimetres in the case of one radar installation and 250 millimetres in the case of the other on ships of 10,000 tons or over.

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Source: https://www.legislation.gov.uk/uksi/1993/69/regulation/27 (the official version)
Page: https://openlegislation.uk/merchant-shipping-navigational-equipment-regulations-1993/regulation-27
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.