1.1 SOLAS REGULATION II-1/3-6, SECTION 1
Interpretation
Oil tankers
This regulation is only applicable to oil tankers having integral tanks
for carriage of oil in bulk, which is contained in the definition of oil in Annex
I of MARPOL. Independent oil tanks can be excluded. Regulation II-1/3-6 should not normally be applied to FPSO
or FSU unless the Administration decides otherwise.
Technical background
Means of access specified in the Technical provisions contained in resolution MSC.158(78) are not specific with respect to the application
to integral cargo oil tanks or also to independent cargo oil tanks. Enhanced survey
programme (ESP) requirements of oil tankers have been established assuming the
target cargo oil tanks are integral tanks. The means of access regulated under regulation II-1/3-6 is for overall and close-up inspections
as defined in regulation IX/1. Therefore it is assumed that the target
cargo oil tanks are those of ESP, i.e. integral cargo tanks. Regulation II-1/3-6 is applicable to new, purpose-built
FPSO or FSU if they are subject to the scope of the 2011 ESP
Code (resolution A.1049(27), as amended). Considering that the principles
of the Technical provisions for means of access for inspections (resolution MSC.158(78)) recognize that permanent means of access should
be considered and provided for at the design stage so that, to the maximum extent
possible, they can be made an integral part of the designed structural arrangement,
regulation II-1/3-6 is not considered applicable to an
FPSO/FSU that is converted from an existing tanker.
Reference
SOLAS regulation IX/1 and the 2011 ESP
Code, as amended.
1.2 SOLAS REGULATION II-1/3-6, PARAGRAPH 2.1
Interpretation
Each space for which close-up inspection is not required such as fuel oil
tanks and void spaces forward of cargo area, may be provided with a means of access
necessary for overall survey intended to report on the overall conditions of the
hull structure.
1.3 SOLAS REGULATION II-1/3-6, PARAGRAPH 2.2
Interpretation
Some possible alternative means of access are listed under paragraph 3.9
of the Technical provisions for means of access for inspections. Always subject to
acceptance as equivalent by the Administration, alternative means such as an
unmanned robot arm, ROVs and dirigibles with necessary equipment of the permanent
means of access for overall and close-up inspections and thickness measurements of
the deck head structure such as deck transverses and deck longitudinals of cargo oil
tanks and ballast tanks, should be capable of:
Technical background
Innovative approaches, in particular the development of robots in place of elevated
passageways, are encouraged and it is considered worthwhile to provide the
functional requirement for the innovative approach.
1.4 SOLAS REGULATION II-1/3-6, PARAGRAPH 2.3
Interpretation
Inspection
The means of access arrangements, including portable equipment and attachments,
should be periodically inspected by the crew or competent inspectors as and when it
is going to be used to confirm that the means of access remain in serviceable
condition.
Procedures
1 Any Company authorized person using the means of access should assume the role of
inspector and check for obvious damage prior to using the access arrangements.
Whilst using the means of access, the inspector should verify the condition of the
sections used by close-up examination of those sections and note any deterioration
in the provisions. Should any damage or deterioration be found, the effect of such
deterioration should be assessed as to whether the damage or deterioration affects
the safety for continued use of the access. Deterioration found that is considered
to affect safe use should be determined as "substantial damage" and measures should
be put in place to ensure that the affected section(s) are not to be further used
prior to effective repair.
2 Statutory survey of any space that contains means of access should include
verification of the continued effectiveness of the means of access in that space.
Survey of the means of access should not be expected to exceed the scope and extent
of the survey being undertaken. If the means of access is found deficient the scope
of survey should be extended if this is considered appropriate.
3 Records of all inspections should be established based on the requirements detailed
in the ship's Safety Management System. The records should be readily available to
persons using the means of access and a copy attached to the Ship Structure Access
Manual. The latest record for the portion of the means of access inspected should
include as a minimum the date of the inspection, the name and title of the
inspector, a confirmation signature, the sections of means of access inspected,
verification of continued serviceable condition or details of any deterioration or
substantial damage found. A file of permits issued should be maintained for
verification.
Technical background
It is recognized that means of access may be subject to deterioration in the long
term due to corrosive environment and external forces from ship motions and sloshing
of liquid contained in the tank. Means of access therefore should be inspected at
every opportunity of tank/space entry. The above interpretation should be contained
in a section of the Ship Structure Access Manual.
1.5 SOLAS REGULATION II-1/3-6, PARAGRAPH 3.1
Interpretation
1 Access to a double-side skin space of bulk carriers may be either from a topside
tank or double-bottom tank or from both.
2 The wording "not intended for the carriage of oil or hazardous cargoes" applies
only to "similar compartments", i.e. safe access can be through a pump-room, deep
cofferdam, pipe tunnel, cargo hold or double-hull space.
Technical background
Unless used for other purposes, the double-side skin space should be designed as a
part of a large U-shaped ballast tank and such space should be accessed through the
adjacent part of the tank, i.e. topside tank or double-bottom/bilge hopper tank.
Access to the double-side skin space from the adjacent part rather than direct from
the open deck is justified. Any such arrangement should provide a directly routed,
logical and safe access that facilitates easy evacuation of the space.
1.6 SOLAS REGULATION II-1/3-6, PARAGRAPH 3.2
Interpretation
1 A cargo oil tank of less than 35 m length without a swash bulkhead requires only
one access hatch.
2 Where rafting is indicated in the ship structures access manual as the
means to gain ready access to the under-deck structure, the term "
similar
obstructions" referred to in the regulation includes internal structures
(e.g. webs > 1.5 m deep) which restrict the ability to raft (at the maximum water
level needed for rafting of under-deck structure) directly to the nearest access
ladder and hatchway to deck. When rafts or boats alone, as an alternative means of
access, are allowed under the conditions specified in the
2011 ESP
Code, permanent means of access are to be provided to allow safe entry
and exit. This means:
-
.1 access direct from the deck via a vertical ladder and
small platform fitted approximately 2 m below the deck in each bay; or
-
.2 access to the deck from a longitudinal permanent platform
having ladders to the deck in each end of the tank. The platform should,
for the full length of the tank, be arranged in level with, or above,
the maximum water level needed for rafting of the under-deck structure.
For this purpose, the ullage corresponding to the maximum water level
should not be assumed more than 3 m from the deck plate measured at the
midspan of deck transverses and in the middle length of the tank (see
figure below). A permanent means of access from the longitudinal
permanent platform to the water level indicated above should be fitted
in each bay (e.g. permanent rungs on one of the deck webs inboard of the
longitudinal permanent platform).
1.7 SOLAS REGULATION II-1/3-6, PARAGRAPH 4.1
Interpretation
1 The access manual should address spaces listed in paragraph 3 of
regulation II-1/3-6. As a minimum the English
version should be provided. The ship structure access manual should contain at least
the following two parts:
-
Part 1: Plans, instructions and inventory required by
paragraphs 4.1.1 to 4.1.7 of regulation II-1/3-6. This part
should be approved by the Administration or the organization recognized
by the Administration.
-
Part 2: Form of record of inspections and maintenance, and
change of inventory of portable equipment due to additions or
replacement after construction. This part should be approved for its
form only at new building.
2 The following matters should be addressed in the ship structure access manual:
-
.1 the access manual should clearly cover scope as specified in the
regulations for use by crews, surveyors and port State control officers;
-
.2 approval/re-approval procedure for the manual, i.e. any changes of the
permanent, portable, movable or alternative means of access within the
scope of the regulation and the Technical provisions are subject to
review and approval by the Administration or by the organization
recognized by the Administration;
-
.3 verification of means of access should be part of the safety
construction survey for continued effectiveness of the means of access
in that space which is subject to the statutory survey;
-
.4 inspection of means of access by the crew and/or a
competent inspector of the company as a part of regular inspection and
maintenance (see interpretation of paragraph 2.3 of regulation II-1/3-6);
-
.5 actions to be taken if means of access is found unsafe to use; and
-
.6 in case of use of portable equipment plans showing the means of access
within each space indicating from where and how each area in the space
can be inspected.
1.8 SOLAS REGULATION II-1/3-6, PARAGRAPH 4.2
Interpretation
1 Critical structural areas should be identified by advanced calculation techniques
for structural strength and fatigue performance, if available, and feedback from the
service history and design development of similar or sister ships.
2 Reference should be made to the following publications for critical structural
areas, where applicable:
-
.1 oil tankers: Guidance Manual for Tanker Structures by
TSCF;
-
.2 bulk carriers: Bulk Carriers Guidelines for Surveys,
Assessment and Repair of Hull Structure by IACS; and
-
.3 oil tankers and bulk carriers: the 2011 ESP Code (resolution A.1049(27), as
amended).
Technical background
These documents contain the relevant information for the present ship
types. However, identification of critical areas for new double-hull tankers and
double-side skin bulk carriers of improved structural design should be made by
structural analysis at the design stage, this information should be taken into
account to ensure appropriate access to all identified critical areas.
1.9 SOLAS REGULATION II-1/3-6, PARAGRAPH 5.1
Interpretation
The minimum clear opening of 600 mm x 600 mm may have corner radii up to
100 mm maximum. The clear opening is specified in MSC/Circ.686/Rev.1 to keep the
opening fit for passage of personnel wearing a breathing apparatus. In such a case
where, as a consequence of structural analysis of a given design the stress should
be reduced around the opening, it is considered appropriate to take measures to
reduce the stress such as making the opening larger with increased radii, e.g. 600 x
800 with 300 mm radii, in which a clear opening of 600 x 600 mm with corner radii up
to 100 mm maximum fits.
Technical background
The interpretation is based upon the established Guidelines in MSC/Circ.686/Rev.1.
Reference
Paragraph 9 of the annex to MSC/Circ.686/Rev.1.
1.10 SOLAS REGULATION II-1/3-6, PARAGRAPH 5.2
Interpretation
1 The minimum clear opening of not less than 600 mm x 800 mm may also
include an opening with corner radii of 300 mm. An opening of 600 mm in height x 800
mm in width may be accepted as access openings in vertical structures where it is
not desirable to make large openings in the structural strength aspects, i.e.
girders and floors in double-bottom tanks.
2 Subject to verification of easy evacuation of an injured person on a stretcher the
vertical opening 850 mm x 620 mm with wider upper half than 600 mm, while the lower
half may be less than 600 mm with the overall height not less than 850 mm is
considered an acceptable alternative to the traditional opening of 600 mm x 800 mm
with corner radii of 300 mm.
3 If a vertical opening is at a height of more than 600 mm steps then handgrips
should be provided. In such arrangements it should be demonstrated that an injured
person can be easily evacuated.
Technical background
The interpretation is based upon the established Guidelines in MSC/Circ.686/Rev.1 and
an innovative design is considered for easy access by humans through the opening.
Reference
Paragraph 11 of the annex to MSC/Circ.686/Rev.1.