INTERNATIONAL CONVENTION FOR THE SAFETY OF LIFE AT SEA, 1974
Unified interpretations of regulations XII/6.5.1 and XII/6.5.3
the 1974 SOLAS Convention as amended by resolution MSC.170(79)
- The Technical Committee of the Assembly at its twenty-fourth session (21 November to 2
December 2005), with a view to providing more specific guidance on vague language
contained in IMO instruments which is open to different interpretations, approved the
interpretations of regulations XII/6.5.1 and XII/6.5.3 of the
1979 SOLAS Convention as amended by resolution MSC.170(79), set out in the annex.
- Member Governments and international organizations are invited to use the annexed
unified interpretations as guidance when applying relevant provisions of SOLAS chapter
XII to bulk carrier construction, for ships constructed on or after 1 July 2006, and to
bring the unified interpretations to the attention of all parties concerned.
Regulation XII/6.5.1 - Protection of cargo holds from loading/discharge equipment
- The protection of the structure of the cargo holds should be achieved by structural
design features such as mandatory application of classification society "grab
- The protection of hatchways and coamings from grab wire damage may be achieved by
fitting protection bars (e.g., half-round bar) on the hatch-side girder (e.g., upper
portion of top-side tank plates), hatch-end beams and the upper portion of hatch
Regulation XII/6.5.3 - Failure of cargo hold structural members and panels
- Stiffening structural member means a stiffener attached to a structural plating
- For the purpose of this interpretation, cargo area includes hatchway coamings,
top-side tanks, side shells, longitudinal bulkheads of double-side skin construction,
bilge hopper tanks and double bottom, but excludes hatchway covers.
- Structural members of a cargo hold are the hatchway coamings, transverse bulkheads,
panel plates of the top-side tanks and bilge hopper tanks facing the cargo hold, inner
bottom, side shell of single-side skin construction or longitudinal bulkhead of
double-side skin construction.
- The term "single failure of one stiffening structural member" is generally
considered to mean localized mechanical damage such as local permanent deformation,
cracking or weld failure that might result from accidental damage within the cargo
- The design considerations for paragraph 4.1 above should be such that a single
localizeddamage, which is of a size that is likely to be detected, should not lead
to complete collapse of the stiffened panel under a load equal to the maximum
allowable design still water load plus 80% of the maximum lifetime dynamic load.
- If the damage is a crack or welding damage, immediate fracture propagation should
be avoided. This may be achieved by appropriate design and selection of
- The intent of the regulation regarding the external hull envelope within the cargo
area is addressed through the structural design requirements that meet the environmental
and operational loads defined in the relevant requirements of classification societies.