110 
bounding the machinery space located aft. The machinery space shall be treated 
as a single floodable compartment ; 
(c) in tankers not exceeding 150 metres in length, anywhere in the ship's 
length between adjacent transverse bulkheads with the exception of the machin- 
ery space. For tankers of 100 metres or less in length where all requirements of 
paragraph (3) of this Regulation cannot be fulfilled without materially impair- 
ing the operational qualities of the ship, Administrations may allow relaxations 
from these requirements. 
Ballast conditions where the tanker is not carrying oil in cargo tanks excluding 
any oily residues, shall not be considered. 
(2) The following provisions regarding the extent and the character of the 
assumed damage shall apply : 
(a) the extent of side or bottom damage shall be as specified in Regulation 
22 of this Annex, except that the longitudinal extent of bottom damage within 
0.3L from the forward perpendicular shall be the same as for side damage, as 
specified in Regulation 22(1)(a)(i) of the Annex. If any damage of lesser 
extent reults in a more severe condition such damage shall be assumed. 
(b) where the damage involving transverse bulkheads is envisaged as spe- 
cified in sub-paragraphs (1)(a) and (b) of this Regulation, transverse water- 
tight bulkheads shall be spaced at least at a distance equal to the longitudinal 
extent of assumed damage specified in sub-paragraph (a) of this paragraph in 
order to be considered effective. Where transverse bulkheads are spaced at a 
lesser distance, one or more of these bulkheads within such extent of damage 
shall be assumed as non-existent for the purpose of determining flooded com- 
partments. 
(c) Where the damage between adjacent transverse watertight bulkheads is 
envisaged as specified in sub-paragraph (1) (c) of this Regulation, no main trans- 
verse bulkhead or a transverse bulkhead bounding side tanks or double bottom 
tanks shall be assumed damaged, unless: 
(i) the spacing of the adjacent bulkheads is less than the longitudinal 
extent of assumed damage specified in sub-paragraph (a) of this paragraph ; 
or 
(ii) there is a step or a recess in a transverse bulkhead of more than 3.05 
metres in length, located within the extent of penetration of assumed dam- 
age. The step formed by the after peak bulkhead and after peak tank top 
shall not be regarded as a step for the purpose of this Regulation. 
(d) If pipes, ducts or tunnels are situated within the assumed extent of dam- 
age, arrangements shall be made so that progressive flooding cannot thereby 
extend to compartments other than those assumed to be floodable for each case 
of damage. 
(3) Oil tankers shall be regarded as complying with the damage stability 
criteria if the following requirements are met: 
(a) The final waterline, taking into account sinkage, heel and trim, shall be 
below the lower edge of any opening through which progressive flooding may take 
place. Such openings shall include air pipes and those which are closed by means 
of weathertight doors or hatch covers and may exclude those openings closed by 
means of watertight manhole covers and flush scuttles, small watertight cargo 
tank hatch covers which maintain the high integrity of the deck, remotely oper- 
ated watertight sliding doors, and side scuttles of the non-opening type. 
(b) In the final stage of flooding, the angle of heel due to unsymmetrical flood- 
ing shall not exceed 25 degrees, provided that this angle may be increased up to 
30 degrees if no deck edge immersion occurs. 
(c) The stability in the final stage of flooding shall be investigated and may 
be regarded as sufficient if the righting lever curve has at least a range of 20 
degrees beyond the position of equilibrium in association with a maximum resid- 
ual righting lever of at least 0.1 metre. The Administration shall give considera- 
tion to the potential hazard presented by protected or unprotected openings 
which may become temporarily immersed within the range of residual stability. 
(d@) The Administration shall be satisfied that the stability is sufficient during 
intermediate stages of flooding. 
(4) The requirements of paragraph (1) of this Regulation shall be confirmed 
by caleulations which take into consideration the design characteristics of the 
ship, the arrangements, configuration and contents of the damaged compart- 
ments; and the distribution, specific gravities and the free surface effect of 
liquids. The calculations shall be based on the following: 
(a) Account shall be taken of any empty or partially filled tank, the specific 
gravity of cargoes carried, as well as any outflow of liquids from damaged com- 
partments, 
