TANKER
SAFETY
Safety
and Pollution Prevention Initiatives
Based
on the recommendations of the Marine Environment Protection Committee
(MEPC) in the wake of the Erika accident, MSC approved a number
of additional measures to be evaluated by relevant Sub-Committees
which aim to enhance the safety and oil pollution prevention of
oil tankers. The more significant measures include:
- identify
risks associated with the carriage of high density and persistent
oils, and consider providing side/bottom protection of fuel oil
bunker tanks;
- consider
measure to provide a greater level of uniformity for construction
and repair standards;
- evaluate
operating risks unique to double hull tankers considering structural
complexities and arrangements of void and ballast spaces;
- consider
facilitating, from the design stage, arrangements which provide
for increased accessibility and efficiency for maintenance and
inspection of double hull tankers;
- establish
a design philosophy that includes minimum design life and residual
structural redundancy taking into account possible operating errors;
- establish
uniform minimum scantling standards for ship’s structures;
- evaluate
the procedures for surveying, including the need for greater transparency
and standardization of reporting; tighter controls for the completion
of surveys, repairs and thickness measurements; and improving
surveyor qualifications; and
- Re-evaluate
human element aspects including seafarer training, adequacy of
tools and requirements for handling ships in adverse weather,
and safety measures for ship navigation in narrow or densely traveled
waterways. 2.10
Condition
Assessment Scheme
During
the interim period between MEPC 45 (2-6 October 2000) and MSC 73,
informal meetings between several Administrations and industry associations,
including IACS, have taken place with the view to developing regulations
to implement the Condition Assessment Scheme (CAS) which was agreed
to in principle, at MEPC 45.
As
reported in the October 2000 International News Update (Vol.9, No.3),
the MEPC tentatively agreed that CAS should be applied to Category
1 (Pre-MARPOL) and Category 2 (PLSBT MARPOL) oil tankers >20k
deadweight and product carriers >30k deadweight. These
tankers will need to satisfactorily complete, and be certified under,
the CAS in order to operate for a period of time prior to the accelerated
phase out dates scheduled to be approved at MEPC 45 in April 2001.
CAS
builds upon and is carried out in conjunction with the current enhanced
special survey requirements contained in resolution A.744(18). There
are several unique aspects of CAS which are scheduled to be finalized
during an IMO intersessional meeting to be held from 31 January
to 2 February 2001.
These
aspects include:
- Greater emphasis
on pre-survey planning and use of survey and operating history
documentation to develop the survey plan;
- Use of two
exclusive qualified surveyors on board to carry out CAS surveys;
- Greater transparency
and completeness of reporting the results of the CAS Survey; and
- Increased
control of the thickness measurement firm by requiring an exclusive
surveyor on board during the time of measurement.
Two
significant issues remain unresolved. The first addresses whether
a second opinion, as to the condition of the ship under CAS, is
to be rendered by either the flag Administration or another recognized
organization.
The
second concerns whether the organization that issued the ISM Safety
Management Certificate is to carry out audits of the ship’s
safety management system on an annual basis during the period of
validity of the CAS certification. Proponents recognize that CAS
ships may be certified for periods of up to 39 months and in light
of the current requirement for ship board audits to be carried out
every 2-1/2 years there is some concern that the commitment to maintain
such ships (as required under the ISM Code) may, in certain instances,
lapse to a substandard condition.
Longitudinal
Strength
A
new set of amendments to the enhanced survey program as per resolution
A.744(18), as amended, was adopted by resolutions MSC.105(73) and
MSC.108(73). The amendments require that upon completion of renewal
surveys on/after 1 July 2002 on oil tankers, more than 10 years
of age (Special Survey No.3) and >130m in length, the
condition of the longitudinal strength is to be evaluated and comply
with a minimum standard and is to be reported upon in the ship’s
Condition Evaluation Report.
The
maximum diminution of the hull girder longitudinal strength for
three girth belt areas gauged during the renewal survey, after any
renewals or repairs have been carried out, is not to exceed either
10% of the as built hull girder flange area or, alternatively,
10% of the minimum required section modulus, Zmin.
Zmin
is to comply with IACS Unified Requirement (UR) S7 for existing
oil tankers built before 1 July 2002. For new oil tankers
built on/after 1 July 2002, Zmin is not to be less than
the value accepted by the Administration (taking into account IACS
UR’s S7 and S11).
Both
URs S7 and S11 specify that the section modulus is to be greater
than an empirically developed minimum value. UR S11 further specifies
that Zmin is to be determined based on the tanker’s
material strength, deadweight and lightship distribution so as to
provide adequate structural resistance against both still water
and wave shear forces and bending moments.
The
MSC held in abeyance a decision to extend this provision to bulk
carriers pending the completion of the Bulk Carrier FSA Study currently
being conducted under the coordination of the United Kingdom. WP.19
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