CHAPTER 4 SAFETY CLEARANCE, FREEBOARD AND DRAUGHT MARKS 4-1 GENERAL 4-1.1 This chpter specifies the minimum freebord for inlnd wterwy vessels. It lso contins requirements concerning the indiction of the freebord mrk nd drught mrks. 4-1.2 This chpter ssumes tht the nture nd stowge of the crgo, bllst, etc., re such s to ensure dequte stbility nd s to obvite ny excessive structurl ftigue. 4-1.3 Freebords s prescribed in this chpter shll be ssigned on the ssumption, first, tht nvigtion will cese when wether conditions re such tht the mximum wve height defining the zone or zones in which vessel is to nvigte my be exceeded, nd second tht in such conditions vessels lredy under wy will seek shelter s quickly s possible. 4-1.4 The Administrtion my consider it sufficient if the vessel hs been built nd mintined in conformity with the rules of recognized Clssifiction Society. 4-2 TYPES OF VESSELS For the purpose of this chpter, vessels shll be divided into three types: Type A Decked vessels Type B Tnkers Type C Open vessels Type A: Decked vessels: Decked vessels re vessels whose htch covers re stisfctorily strong, rigid nd wtertight for zone 1 nd or spryproof for zones 2 nd 3. Type B: Tnkers nd similr vessels: These vessels hve only smll openings giving ccess to the tnks, the openings being closed by steel or equivlent covers with wtertight fittings. Such vessels hve the following chrcteristics: (i) (ii) Very high wtertight integrity of the exposed deck; Very high resistnce to flooding, through low permebility of the loded comprtments nd through the degree of subdivision pplied in generl. Type C: Open vessels: Open vessels re either vessels whose htch covers re not stisfctorily strong, rigid, spryproof or vessels whose crgo htchwys re open. 4-3 APPLICATION AND DEROGATIONS 4-3.1 The mximum drught level shll be so determined tht both the freebord requirements nd the sfety-distnce requirements re observed. For sfety resons, however, the Administrtion my prescribe higher figure for the freebord. 4-3.2 Vessels so constructed tht ppliction of the provisions of this chpter is unwrrnted or imprcticble shll be ssigned freebords by the Administrtion in such wy tht the sfety conditions re equivlent to those of this chpter. 4-3.3 In the cse of zone 1, derogtions from the conditions of ssignment of freebord my be llowed to vessels to which freebord in excess of the minimum freebord is ssigned, provided tht the sfety conditions re deemed stisfctory by the Administrtion.
4-3.4 1 4-4 DETERMINATION OF FREEBOARDS 4-3 Generl DRAUGHT MARKS AND FREEBOARD MARK Deck line The deck line is the upper edge of horizontl rectngle 300 mm long nd 25 mm wide. This rectngle shll be mrked midships on ech side of the hull, nd its upper edge shll normlly pss through the point where the continution outwrds of the upper surfce of the freebord deck intersects the outer surfce of the shell midships. However, the deck line my lso be mrked t different height provided tht the freebord is corrected ccordingly. 4-3.1 Article 4.04(1) The plne of mximum drught shll be determined in such wy tht the specifictions concerning minimum freebord nd minimum sfety clernce re both met. However, for sfety resons, the inspection body competent uthority my ly down greter vlue for the sfety clernce or freebord. The plne of mximum drught shll be determined t lest for zone 3. 4-3.2 In the cse of zone 1, derogtions from the conditions of ssignment of freebord my be llowed to vessels to which freebord in excess of the minimum freebord is ssigned, provided tht the sfety conditions re deemed stisfctory by the Administrtion. 4-3.3 Article 4.04(2) The plne of mximum drught shll be indicted by mens of highly visible, indelible drught mrks. 4-3.4 Article 4.04(3) The drught mrks for Zone 3 shll consist of rectngle 300 mm long nd 40 mm deep, the bse of which is horizontl nd coincides with the plne of the mximum uthorised drught. Any differing drught mrks shll include such rectngle. 4-3.5 Article 4.04(4) Vessels shll hve t lest three pirs of drught mrks, of which one pir shll be centrlly locted nd the two others locted, respectively, t distnce from the bow nd stern tht is equl to roughly one-sixth of the length. However, (i) where vessel is less thn 40 m in length it will suffice to ffix two pirs of mrks t distnce from the bow nd stern, respectively, tht is equl to qurter of the length; (ii) where vessels re not intended for the crrige of goods, pir of mrks locted roughly hlfwy long the vessel will suffice. 4-3.6 Article 4.04(5) Mrks or indictions which cese to be vlid following further inspection shll be deleted or mrked s being no longer vlid under the supervision of the inspection body. If Drught mrks should dispper, it my only be replced under the supervision of inspection body competent uthority. 4-3.7 Article 4.04(6). Where vessel hs been mesured in implementtion of the 1966 Convention on the Mesurement of Inlnd Nvigtion Vessels nd the plne of the mesurement mrks meets the requirements of this Directive Resolution, those mesurement mrks shll tke the plce of the drught mrks; this shll be mentioned in the Community vessel s certificte. 1 Here we propose to include prgrph which will be connection between freebord for zone 3 nd zones 1 nd 2. For exmple, if the vessel is designed for nvigtion in zones 1 or 2, it shll comply with 4-4.2. If the vessel my perform single voyges in zones 1 nd 2, 4-4.4 my be pplied provided tht
4-3.8 Article 4.04(7). For vessels operting dmitted for opertion on zones of inlnd wterwys other thn Zone 3 (Zones 1, 2 or 4) the bow nd stern pirs of drught mrks provided for in prgrph 4 shll be supplemented by dding verticl line to which one or, in the cse of severl zones, severl dditionl drught lines 150 mm long shll be ffixed towrds the bow, in reltion to the drught mrk for Zone 3. This verticl line nd the horizontl line shll be 30 mm thick. In ddition to the drught mrk towrds the bow of the vessel, the relevnt zone numbers shll be indicted in lettering 60 mm high 40 mm deep (see Figure 1 4-3.8). Figure 1 4-3.8 Mesurement/drught scle 4-3.9 Article 4.05 Mximum loded drught of vessels whose holds re not lwys closed so s to be spry-proof nd wethertight shll be determined s follows. If the plne of mximum drught for Zone 3 of vessel is determined by ssuming tht the holds my be closed in such wy s to mke them spry-proof nd wethertight, nd if the distnce between the plne of mximum drught nd the upper edge of the comings is less thn 500 mm, the mximum drught for siling with uncovered holds shll be determined. The following sttement shll be entered on the Community vessel s certificte: Where the hold htches re totlly or prtly uncovered the vessel my only be loded up to... mm below the drught mrks for Zone 3. 4-3.10 Deck line nd freebord mrk The deck line must be indicted by the upper edge of horizontl rectngle 300 mm long nd 25 mm wide. This rectngle shll be mrked midships on ech side of the hull, nd its
upper edge shll normlly pss through the point where the continution outwrds of the upper surfce of the freebord deck intersects the outer surfce of the shell midships. However, the deck line my lso be mrked t different height provided tht the freebord is corrected ccordingly. The distnces between the deck line nd the freebord mrk must correspond to the sections 4-4.1, 4-4.2 or 4-7. The lower edge of ech freebord line shll correspond to the freebord prescribed for the nvigtion zone concerned. The freebord mrk for vessels for zone 3 consists of horizontl bnd of 300 mm long nd 40 mm width. The freebord mrkfor zones 1 nd 2 shll must consist of ring intersected through its centre by horizontl line which shll be supplemented if necessry by dditionl freebord lines. 30 200 30 30 300 150 Fig. 4-3.10 The width of the ring nd of ll the other lines of the freebord mrk shll be 30 mm; the outer dimeter of the ring shll be 200 mm; the length of the horizontl line intersecting the ring shll be 300 mm; nd the size of the numerls designting the zones shll be 60 x 40 mm (Figure 4-3.10). The centre of the ring shll be plced midships. The lower edge of the horizontl line which intersects the ring shll pss through the centre of the ring nd shll constitute the freebord line. If the vessel is intended to nvigte in severl nvigtion zones, verticl line nd dditionl freebord lines 150 mm in length shll be pplied forwrd of the centre of the ring. The lower edge of ech freebord line shll correspond to the freebord prescribed for the nvigtion zone concerned. If the vessel is mesured in ccordnce with the Convention on the Mesurement of Inlnd Nvigtion Vessels, it shll ber, in ddition to the freebord mrk, mesurement mrk in ccordnce with the requirements of this Convention. The freebord mrk nd the mesurement drught mrk my be combined. In this cse, the width of the freebord mrk line rectngle (the width of the upper line if there re
number of freebord mrks) must be 40 mm. 4-4 FREEBOARD 4-4.1 Minimum freebord in zones 1 nd 2 4-4.1.1 Minimum freebord (F) for vessels of type A Length of the vessel [m] Minimum freebord (F) [mm] Zone 1 Zone 2 30 250 250 40 340 300 50 440 340 60 570 340 70 570 340 80 570 340 Note: In this nd ll subsequent tbles, the vlues for the intermedite lengths of vessels shll be obtined by liner interpoltion. 4-4.1.2 Minimum freebord (F) for vessels of type B Length of the vessel [m] Minimum freebord (F) [mm] Zone 1 Zone 2 30 180 160 40 250 220 50 330 220 60 420 220 70 420 220 80 420 220 4-4.1.3 The minimum freebord of flush-deck vessels should be obtined in the mnner indicted for the vessel of type B. 4-4.1.4 The minimum freebord for vessels of type C, regrdless of length, should be not less thn: For zone 1 1 000 mm zone 2 600 mm. Furthermore, the sum of the freebord nd the height of comings for these vessels must be not less thn: For zone 1 1 200 mm zone 2 1 000 mm. 4-4.1.5 The Administrtion my uthorize corrections for the freebord for vessels with poop, sheer nd forecstle, providing tht such corrections re clculted in conformity with the rules of the Administrtion or of recognized Clssifiction Society. 4-4.2 Specil requirements for Minimum freebord in zone 3 4-4.2.1 The bsic freebord of vessels with continuous deck without superstructures nd sheer shll be 150 mm.
4-4.2.2 The Administrtion my uthorize correction for the freebord for vessels with superstructures nd sheer providing tht such correction is clculted in conformity with the rules of the Administrtion or of recognized Clssifiction Society. 4.02(2) The freebord of vessels with sheer nd superstructures shll be clculted using the following formul: Se Se F 150 (1 ) [mm] 15 where: is correction coefficient tht tkes ccount of ll of the superstructures involved; is coefficient for correcting the effect of the forwrd sheer resulting from the presence of superstructures in the forwrd qurter of length L of the vessel; is coefficient correcting the effect of the ft sheer resulting from the presence of superstructures in the ft qurter of length L of the vessel; Se v is the effective forwrd sheer in mm; Se is the effective ft sheer in mm. 4.02(3) 4-4.2.3 The coefficient is clculted using the following formul: le lem le L where: le m is the effective length, in m, of superstructure locted in the medin prt corresponding to hlf of length L of the vessel; le v is the effective length, in m, of superstructure in the forwrd qurter of vessel length L; le is the effective length, in m, of superstructure in the ft qurter of vessel length L. The effective length of superstructure is clculted using the following formule: le m b h 1 2.5 1.5 [ m] B 0,36 where: l is the effective length, in m, of the superstructure involved; b is the width, in m, of the superstructure involved; В 1 is the width of the vessel, in m, mesured on the outside of the verticl sidepltes t deck level hlfwy long the superstructure involved; h is the height, in m, of the superstructure involved. However, in the cse of htches, h is obtined -y reducing the height of the comings by hlf of the sfety distnce ccording to Article 4.01(1) nd (2) 4-5.2 nd 4-5.3. In no cse will vlue exceeding 0,36 m be tken for h. b If or B B1 b is less thn 0,6 the effective length le of the superstructure will be zero.
4.02(4) 4-4.2.4 Coefficients β v nd β re clculted using the following formule: 3 lev v l L l 3 le L 4.02(5) 4-4.2.5 The effective ft/forwrd sheers Se v /Se re clculted using the following formule: Se S p where: Se v S v p S v is the ctul forwrd sheer, in mm; however S v shll not be tken to be more thn 1 000 mm; S is the ctul ft sheer, in mm; however S my not be tken to be more thn 500 mm; p is coefficient clculted using the following formul: x p 4 L x is the bsciss, mesured from the extremity of the point where the sheer is 0,25 S v or 0,25 S (see figure). However, coefficient p will not be tken to be more thn 1. 4.02(6) 4-4.2.6 If β Se is greter thn βv Sev, the vlue of β Se will be tken s being the vlue for βv Sev. 4.03 4-4.2.7.In view of the reductions referred to in Article 4.02 4-4.2.2 4-4.2.6 the minimum freebord shll not be less then 0 mm. 4-4.3.8 The Administrtion my uthorize correction for the freebord for vessels with superstructures nd sheer providing tht such correction is clculted in conformity with the rules of the Administrtion or of recognized Clssifiction Society.
4-5 SAFETY CLEARANCE 4-5.1 4-4.3.11 For vessels of type A nd type B, the sfety clernce s defined in 1-2 must not be less thn 600 mm for zone 2. For vessels of type C, s well s other vessels nvigting with open holds, this distnce shll be incresed to by 400 mm in zone 2. However, this increse pplies only to the comings of open holds. 4-5.2 For vessels of types A nd B nvigting in zone 3, the sfety clernce must not be less thn 300 mm. 4-5.3 For vessels of the type C nvigting in zone 3, the sfety clernce shll be incresed in such wy tht ech of those openings tht cnnot be closed by spry-proof nd wethertight wtertight devices shll be t lest 500 mm from the plne of mximum drught must not be less thn 500 mm. 4-6 Arrngement of openings nd comings 4-6.1 All outside doors of superstructure, deckhouses nd compnionwys, situted on the freebord deck shll be wtertight on vessels in zone 1 nd spryproof on vessels in zones 2 nd 3. 4-6.2 The comings of htchwys, compnionwys nd ccess openings to superstructures shll be not less thn 300 mm high on vessels in zone 1 nd 150 mm on vessels in zone 2. 4-6.3 If the height of the comings is less thn tht required by this chpter, the minimum freebord height shll be incresed by the difference between the height required in 4-6.2 nd the ctul height of the comings. 4-6.4 The freebord height my not be reduced owing to n increse in the height of comings below the figure indicted in 4-6.2. 4-4.6.5 Exposed crgo htchwys nd other htchwys on the freebord deck shll be fitted with wtertight closures on vessels in zone 1 nd spryproof closures on vessels in zones 2 nd 3. 4-6.5 Ventiltor heds on the exposed prts of the freebord deck shll be fitted with strong steel coming of height not less thn tht required for htchwy comings. Ventiltor heds for vessels in zone 1 must hve wtertight closures. 4-6.6 Pipe outlets in the ship s sides below the freebord deck shll be fitted with efficient nd ccessible devices to prevent wter from entering the vessel. 4-6.7 On vessels in zone 1, side scuttles in spces below the freebord deck, windows in superstructures, deckhouses nd compnionwys nd windows in skylights on the freebord deck shll must be wtertight. In ddition, side scuttles in spces below the freebord deck shll must be provided with permnently ttched dedlights. The distnce between side scuttles in the shell nd the mximum drught level shll must not be less thn 300 mm. 4-6.8 Skylights nd windows must be of sturdy construction. 4-6.9 On vessels in zone 2, skylights nd windows must be fitted with spryproof covers which shll be permnently ttched if the lowest prt of the openings flls within the sfety clernce prescribed for the comings of uncovered holds (see 4-5.1). In this cse, the height ( h ) of the superstructures in which the openings re provided is limited to the lowest point of these openings.
4-4.3.11 For vessels of type A nd type B, the sfety clernce s defined in 1-2 must not be less thn 600 mm for zone 2. For vessels of type C, s well s other vessels nvigting with open holds, this distnce shll be incresed to 400 mm in zone 2. However, this increse pplies only to the comings of open holds. 4-6.10 The covers of Kingston vlves nd ice boxes must be wtertight. 4-6.11 The scuppers nd freeing ports in bulwrks shll be of sufficient size to drin the decks of shipped wter. 4-7 Specil requirements for sfety clernce nd freebord in zone 4 Article 19b.01(1) 4-7.1 By wy of derogtion from Article 4.01(1) nd (2) 4-5.2 nd 4-5.3, the sfety clernce of doors nd openings other thn hold htches for vessels nvigting on Zone 4 wterwys is reduced s follows: (i) for openings which cn be closed spry-proof nd wethertight, to 150 mm; (ii)for openings which cnnot be closed spry-proof nd wethertight, to 200 mm. Article 19b.01(1) 4-7.2 By wy of derogtion from Article 4.02 4-4.2.1, the minimum freebord of vessels nvigting on Zone 4 wterwys is 0 mm, if the sfety clernce ccording to prgrph I 4-7.1 is respected.