TechnicalNoticeonMSC.1-Circ.1577-theunifiedinterpretationontheapplicationofCOLREGwithrespecttotheplacementofsidelightsissuedbyIMO

CCSTechnical Information(2018)Technical Information No.24 Total No.350Apr.20,2018(Total 2 pages)To:Related departments in CCS Headquarters,each plan approval center,each branch (office),concerned shipyards,ship designers,shipping management companies and shipownersTechnical Notice on MSC.1/Circ.1577-the unified interpretation onthe application of COLREG with respect to the placement ofsidelights issued by IMO1.BackgroundThe Maritime Safety Committee (MSC)of the International Maritime Organization(IMO),at its ninety-eighth session held from 7 to 16 June 2017,approved the unifiedinterpretation on the application of COLREG with respect to the placement ofsidelights (MSC.1/Circ.1577).This circular is used as guidance on the placement ofsidelights according to annex I/9(a)(i)and annex I/10(a)(i)of COLREG 1972,asamended,on ships contracted for construction on or after 1 July 2019.2.Main contents(1)Interpretations with respect to sidelights'horizontal sectorsCOLREG annex I,section 9(a)(i)would require the full intensity of the sidelights tobe maintained in the forward direction of 1 outside the prescribed sector(one-degreetoe-in sector)with the practical cut-off between 1 and 3.This is needed to enableother vessels to determine a "head-on-situation"as per COLREG rule 14.