MSC.1/Circ.1464

24 June 2013

As amended by MSC.1/Circ.1464/Rev.1/Corr.2 (9 June 2017)

 

UNIFIED INTERPRETATIONS OF SOLAS CHAPTERS II-1 AND XII, OF THE TECHNICAL PROVISIONS FOR MEANS OF ACCESS FOR INSPECTIONS (RESOLUTION MSC.158(78)) AND OF THE PERFORMANCE STANDARDS FOR WATER LEVEL DETECTORS ON BULK CARRIERS (RESOLUTION MSC.145(77))

 

1          The Maritime Safety Committee, at its ninety-second session (12 to 21 June 2013), approved unified interpretations of the provisions of SOLAS chapters II-1 and XII, the Technical provisions for means of access for inspections (resolution MSC.158(78)) and of the Performance standards for water level detectors on bulk carriers (resolution MSC.145(77)), as set out in the annex, following the recommendations made by the Sub-Committee on Ship Design and Equipment at its fifty-seventh session, with a view to ensuring a uniform approach towards the application of the provisions of SOLAS chapters II-1 and XII.

 

2          Member Governments are invited to use the annexed interpretations when applying relevant provisions of SOLAS chapters II-1 and XII, and to bring them to the attention of all parties concerned.

 

3          This circular supersedes circulars MSC.1/Circ.1176 and MSC.1/Circ.1197.

 

ANNEX

 

UNIFIED INTERPRETATIONS OF SOLAS CHAPTERS II-1 AND XII, OF THE TECHNICAL PROVISIONS FOR MEANS OF ACCESS FOR INSPECTIONS (RESOLUTION MSC.158(78)) AND OF THE PERFORMANCE STANDARDS FOR WATER LEVEL DETECTORS ON BULK CARRIERS (RESOLUTION MSC.145(77))

 

Table of contents

 

1          SOLAS regulation II-1/3-6 – Access to and within spaces in, and forward of,  the cargo area of oil tankers and bulk carriers

 

2          Technical provisions for means of access for inspections (resolution MSC.158(78))

 

3          SOLAS regulation II-1/26 – General

 

4          SOLAS regulations II-1/40 – General – and II-1/41 – Main source of electrical power and lighting systems

 

5          SOLAS regulation II-1/41 – Main source of electrical power and lighting systems

 

6          SOLAS regulations II-1/42 and II-1/43 – Emergency source of electrical power in passenger and cargo ships

 

7          SOLAS regulation II-1/44 – Starting arrangements for emergency generating sets

 

8          SOLAS chapter II-1, parts B-2 – Subdivision, watertight and weathertight integrity – and B-4 – Stability management

 

9          SOLAS regulation XII/12 – Hold, ballast and dry space water ingress alarms, including the Performance standards for water level detectors on bulk carriers (resolution MSC.145(77))

 

10        SOLAS regulation XII/13 – Availability of pumping systems

 

1          SOLAS REGULATION II-1/3-6 – ACCESS TO AND WITHIN SPACES IN THE CARGO AREA OF OIL TANKERS AND BULK CARRIERS

 

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 FSO unless the Administration decides otherwise.

 

Technical background

 

Means of Access (MA) 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. ESP requirements of oil tankers have been established assuming the target cargo oil tanks are integral tanks. The MA regulated under SOLAS 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 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 resolution A.744(18), 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 (TP). 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:

 

.1       safe operation in ullage space in gas-free environment; and

 

.2       introduction into the place directly from a deck access.

 

Technical background

 

Innovative approaches, in particular a 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 MA 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 MAs remain in serviceable condition.

 

Procedures

 

1          Any Company authorized person using the MA should assume the role of inspector and check for obvious damage prior to using the access arrangements. Whilst using the MA, 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 MA should include verification of the continued effectiveness of the MA in that space. Survey of the MA should not be expected to exceed the scope and extent of the survey being undertaken. If the MA 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 MAs and a copy attached to the MA Manual. The latest record for the portion of the MA inspected should include as a minimum the date of the inspection, the name and title of the inspector, a confirmation signature, the sections of MA 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 MA 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. MA therefore should be inspected at every opportunity of tank/space entry. The above interpretation should be contained in a section of the MA Manual.

 

1.5       SOLAS REGULATION II-1/3-6, PARAGRAPH 3.1

 

Interpretation

 

Access to a double-side skin space of bulk carriers may be either from a topside tank or double-bottom tank or from both.

 

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 ESP Code (resolution A.1049(27)), 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 is to be assumed not 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 MA should be part of the safety construction survey for continued effectiveness of the MA in that space which is subject to the statutory survey;

 

.4       inspection of MA 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 SOLAS regulation II-1/3-6);

 

.5       actions to be taken if MA 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 4.2

 

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: 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 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.

 

Reference

 

Paragraph 9 of the annex to MSC/Circ.686.

 

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 and an innovative design is considered for easy access by humans through the opening.

 

Reference

 

Paragraph 11 of the annex to MSC/Circ.686.

 

2          TECHNICAL PROVISIONS FOR MEANS OF ACCESS FOR INSPECTIONS (RESOLUTION MSC.158(78))

 

2.1       PARAGRAPH 1.3

 

Interpretation

 

A "combined chemical/oil tanker complying with the provisions of the IBC Code" is a tanker that holds both a valid IOPP certificate as a tanker and a valid certificate of fitness for the carriage of dangerous chemicals in bulk, i.e. a tanker that is certified to carry both oil cargoes under MARPOL Annex I and Chemical cargoes in chapter 17 of the IBC Code either as full or part cargoes. The Technical provisions should be applied to ballast tanks of combined chemical/oil tankers complying with the provisions of the IBC Code.

 

2.2       PARAGRAPH 1.4

 

Interpretation

 

1          In the context of the above requirement, the deviation should be applied only to distances between integrated PMA that are the subject of paragraph 2.1.2 of table 1.

 

2          Deviations should not be applied to the distances governing the installation of under-deck longitudinal walkways and dimensions that determine whether permanent access is required or not, such as height of the spaces and height to elements of the structure (e.g. cross-ties).

 

2.3       PARAGRAPH 3.1

 

Interpretation

 

The permanent means of access to a space can be credited for the permanent means of access for inspection.

 

Technical background

 

The Technical provisions specify means of access to a space and to hull structure for carrying out overall and close-up surveys and inspections. Requirements of MA to hull structure may not always be suitable for access to a space. However, if the MA for access to a space can also be used for the intended surveys and inspections such MA can be credited for the MA for use for surveys and inspections.

 

2.4       PARAGRAPH 3.3

 

Interpretation

 

1          Sloping structures are structures that are sloped by 5 or more degrees from horizontal plane when a ship is in an upright position at even-keel.

 

2          Guard rails should be fitted on the open side and should be at least 1,000 mm in height. For stand-alone passageways guard rails should be fitted on both sides of these structures. Guardrail stanchions are to be attached to the PMA. The distance between the passageway and the intermediate bar and the distance between the intermediate bar and the top rail should not be more than 500 mm.

 

3          Discontinuous top handrails are allowed, provided the gap does not exceed 50 mm. The same maximum gap is to be considered between the top handrail and other structural members (i.e. bulkhead, web frame, etc.). The maximum distance between the adjacent stanchions across the handrail gaps is to be 350 mm where the top and mid handrails are not connected together and 550 mm when they are connected together. The maximum distance between the stanchion and other structural members is not to exceed 200 mm where the top and mid handrails are not connected together and 300 mm when they are connected together. When the top and mid handrails are connected by a bent rail, the outside radius of the bent part is not to exceed 100 mm (see figure below).

 

 

4          Non-skid construction is such that the surface on which personnel walks provides sufficient friction to the sole of boots even if the surface is wet and covered with thin sediment.

 

5          "Substantial construction" is taken to refer to the as designed strength as well as the residual strength during the service life of the vessel. Durability of passageways together with guard rails should be ensured by the initial corrosion protection and inspection and maintenance during services.

 

6          For guard rails, use of alternative materials such as GRP should be subject to compatibility with the liquid carried in the tank. Non-fire resistant materials should not be used for means of access to a space with a view to securing an escape route at a high temperature.

 

7          Requirements for resting platforms placed between ladders should be equivalent to those applicable to elevated passageways.

 

Reference

 

Paragraph 10 of the annex to MSC/Circ.686.

 

2.5       PARAGRAPH 3.4

 

Interpretation

 

Where the vertical manhole is at a height of more than 600 mm above the walking level, it should be demonstrated that an injured person can be easily evacuated.

 

2.6       PARAGRAPH 3.5

 

Interpretation

 

MA for access to ballast tanks, cargo tanks and spaces other than fore peak tanks:

 

For oil tankers:

 

1          Tanks and subdivisions of tanks having a length of 35 m or more with two access hatchways:

 

First access hatchway: Inclined ladder or ladders should be used.

 

Second access hatchway:

 

.1           A vertical ladder may be used. In such a case where the vertical distance is more than 6 m, vertical ladders should comprise one or more ladder-linking platforms spaced not more than 6 m apart vertically and displaced to one side of the ladder.

 

              The uppermost section of the vertical ladder, measured clear of the overhead obstructions in the way of the tank entrance, should not be less than 2.5 m but not exceed 3.0 m and should comprise a ladder-linking platform which should be displaced to one side of a vertical ladder. However, the vertical distance of the uppermost section of the vertical ladder may be reduced to 1.6 m, measured clear of the overhead obstructions in the way of the tank entrance, if the ladder lands on a longitudinal or athwartship permanent means of access fitted within that range; or

 

.2           Where an inclined ladder or combination of ladders is used for access to the space, the uppermost section of the ladder, measured clear of the overhead obstructions in the way of the tank entrance, should be vertical for not less than 2.5 m but not exceed 3.0 m and should comprise a landing platform continuing with an inclined ladder. However, the vertical distance of the uppermost section of the vertical ladder may be reduced to 1.6 m, measured clear of the overhead obstructions in the way of the tank entrance, if the ladder lands on a longitudinal or athwartship permanent means of access fitted within that range. The flights of the inclined ladders are normally to be not more than 6 m in vertical height. The lowermost section of the ladders may be vertical for the vertical distance not exceeding 2.5 m.