chart and information system, which is accepted as complying with the conventional paper charts required by Regulation V/19 of the 1974 IMO SOLAS Convention. as amended. The performance requirements for ECDIS are defined by IMO and the consequent test standards have been developed by the International Electrotechnical Commission (IEC) in International Standard IEC 61174. In the future, the ENC will be part of a product specification family which is based on the "IHO Universal Hydrographic Data Model", known as S-100. The product specification number S-101 has been assigned to the ENC. See also e-Navigation concept Raster Navigational Charts (NOAA) Navionics C-MAP References Further reading WEINTRIT Adam: The Electronic Chart Display and Information System (ECDIS). An Operational Handbook. A Balkema Book. CRC Press, Taylor & Francis Group, Boca Raton – London - New York - Leiden, 2009. (), http://www.crcpress.com/product/isbn/9780415482462 External links IMO Electronic Chart Overview Transas Electronic Navigational Charts, World Folio International Centre for ENCs, one of two RENCs in the world PRIMAR, one of two RENCs in the world United Kingdom Hydrographic Office Electronic Chart Centre (ECC) Product Survey ECDIS - ECS+ software Office of Coast Survey, has free download of ENCs for US. Inland Electronic Navigation Charts (US) Open Electronic Navigation Charts Directory NOAA ENC Chart Viewer Electronic navigation Navigational aids Nautical charts