5                       WEATHERTIGHT INTEGRITY

            Objective:- This section is intended to outline standards to be achieved for weathertight integrity. As far as is as practicable the standards of the 1966 ICLL are to be adhered to. However, due consideration may be given to arrangements that provide an equivalent level of safety in respect of the risks of down flooding and green sea loading.

                        Virtual Freeboard Deck

For the purposes of this section only, where actual freeboard to the weather deck exceeds that required by ICLL 66 by at least one standard superstructure height, openings on that deck, abaft of the forward quarter, may be assumed to be in position 2. This is to be taken, unless otherwise stated, as defined in ICLL 66.

For vessels up to 75m load line length, a standard superstructure height is to be taken as 1.8m. For vessels over 125m load line length, this is to be taken as 2.3m. Superstructure heights for vessels of intermediate lengths should be obtained by interpolation.

5.1                    Hatchways and Skylight Hatches

5.1.1                 General requirements

5.1.1.1             All openings leading to spaces below the weather deck not capable of being closed weathertight, must be enclosed within either an enclosed superstructure or a weathertight deckhouse of adequate strength meeting with the requirements of the Load Line assigning authority.

5.1.1.2             All exposed hatchways which give access to spaces below the weather deck are to be of substantial weathertight construction and provided with efficient means of closure. Weathertight hatch covers should be permanently attached to the vessel and provided with adequate arrangements for securing the hatch closed.

5.1.1.3             Hatches which are designated for escape purposes should be provided with covers which are to be openable from either side and in the direction of escape they are to be openable without a key. All handles on the inside are to be non removable. An escape hatch should be readily identified and easy and safe to use, having due regard to its position.  

5.1.2                 Hatchways which are open at sea

           In general, hatches should be kept closed at sea.   However, hatchways which may be kept open for access at sea are to be kept as small as practicable (a maximum of 1 square metre in clear area), and fitted with coamings of at least 300mm in height. Hatchways should be as near to the centreline as practicable, especially on sailing vessels. Covers of hatchways are to be permanently attached to the hatch coamings and, where hinged, the hinges are to be located on the forward side.

5.2                    Doorways and Companionways

5.2.1                 Doorways located above the weather deck

5.2.1.1                         Exposed doors in deckhouses and superstructures that give access to spaces below the weather deck, are to be weathertight and door openings should have coaming heights of at least:

           Location A       The door is in the forward quarter length of the vessel and is used when the vessel is at sea.

           Location B        The door is in an exposed forward facing location aft of the forward quarter length.

           Location C       Above the surface of the deck when the door is in a protected location aft of the forward quarter length.

5.2.1.2                         Weathertight doors should be arranged to open outwards and when located in a house side, be hinged at the forward edge.   Alternative closing arrangements will be considered providing it can be demonstrated that the efficiency of the closing arrangements and their ability to prevent the ingress of water will not impair the safety of the vessel.

5.2.1.3                         An access door leading directly to the engine room from the weather deck should be fitted with a coaming of height of;

5.2.1.4                         Coaming height, construction and securing standards for weathertight doors which are provided for use only when the vessel is in port or at anchor in calm sheltered waters and are locked closed when the vessel is at sea, may be considered individually.

5.2.2                 Companion hatch openings

5.2.2.1                         Companionway hatch openings which give access to spaces below the weather deck should be fitted with a coaming, the top of which is at least 300mm above the deck, or 150mm in the case of Short Range Yachts.

5.2.2.2                         Washboards may be used to close the vertical opening.   When washboards are used, they should be so arranged and fitted that they will not be dislodged readily.   Whilst stowed, provisions are to be made to ensure that they are retained in a secure location.

5.2.2.3             The maximum breadth of an opening in a companion hatch should not exceed 1 metre.

5.3                    Skylights

5.3.1                 All skylights should be of efficient weathertight construction and should be located on or as near to the centreline of the vessel as practicable.

5.3.2                 If they are of the opening type they should be provided with efficient means whereby they can be secured in the closed position.

5.3.3                 Skylights which are designated for escape purposes should be openable from either side and in the direction of escape they are to be openable without a key. All handles on the inside are to be non removable. An escape skylight should be readily identified and easy and safe to use, having due regard to its position.

5.3.4                 The skylight glazing material and its method of securing within the frame should meet an appropriate national or international standard. Recognised Classification Society rules for "ships" are considered to meet these requirements. Where a recognised Classification Society produces alternative rules for "pleasure vessels" or "yachts", these are considered appropriate for Short Range Yachts.

           A minimum of one portable cover for each size of glazed opening should be provided which can be accessed rapidly and efficiently secured in the event of a breakage of the skylight.

5.4                    Portlights

5.4.1                 Portlights should be of strength appropriate to location in the vessel and meet an appropriate national or international standard. Recognised Classification Society rules for "ships" are considered to meet these requirements. Where a recognised Classification Society produces alternative rules for "pleasure vessels" or "yachts", these are considered appropriate for Short Range Yachts. With regard to structural fire protection, the requirements for the construction of certain portlights should meet the requirements of Section 14.

5.4.2                 In general, all portlights fitted in locations protecting openings to spaces below the weather deck or fitted in the hull of the vessel should be provided with a permenantly attached deadlight which is to be capable of securing the opening watertight in the event of a breakage of the portlight glazing.   Proposals to fit portable deadlights will be subject to special consideration and approval by the Administration, having regard for the location of the portlights and the ready availability of deadlights.   Consideration should be given to the provision of operational instructions to the Master as to when deadlights must be applied to portlights.

5.4.3                 Portlights fitted in the hull of the vessel below the level of the freeboard deck should be either non-opening or of a non readily opening type and be in accordance with a standard recognised by the administration.   The sill height of the portlights should be at least 500mm or 2.5% of the breadth of the vessel, whichever is the greater, above the all seasons load line assigned to the vessel.   Portlights of the non readily opening type must be secured closed when the vessel is in navigation.

5.4.4                 Portlights should not be fitted in the hull in way of the machinery space.

5.5                    Windows

5.5.1                     Windows should be of strength appropriate to location in the vessel and meet the requirements of BSMA 25 or ISO [***]. Where a recognised Classification Society produces alternative rules for "pleasure vessels" or "yachts", these are considered appropriate for Short Range Yachts.

5.5.2                 Where the glazing material, glazing thickness, or fixing of the windows does not meet the requirements of a recognised standard, windows may be tested, to the satisfaction of the Administration, at a minimum of 4 times the required design pressure derived from an appropriate national or international standard. For windows fitted with storm shutters, see 5.5.5, or Short Range Yachts, test pressures may be reduced to 2.5 times the derived design pressure.

5.5.3                 In general, windows fitted in superstructures or weathertight deckhouses are to be substantially framed and efficiently secured to the structure. The glass is to be of the toughened safety glass type.

5.5.4                 In general, windows should not be fitted in the main hull below the level of the freeboard deck.   Proposals to fit windows in the main hull below the level of the freeboard deck will be subject to special consideration and approval by the Administration, having regard for the location and strength of the windows and their supporting structure and, the availability of strong protective covers for the windows.   One item of the special consideration should be operational instructions to the Master as to when the strong protective covers must be applied to windows.

5.5.5                 For all vessels, other than Short Range Yachts, storm shutters are required for all windows in the front and sides of first tier and front windows of the second tier of superstructures or weathertight deckhouses above the freeboard deck. Where windows are of laminated construction and their equivalent toughened safety glass thickness exceeds the requirements of the applied standard by a minimum of 30%, storm shutters need not be carried, but a blanking plate to be provided for each size of window. When storm shutters are interchangeable port and starboard, a minimum of 50% of each size should be provided.

5.5.6                 Side and front windows to the navigating position should not be constructed of polarised or tinted glass. (See Section 18)

5.6                    Ventilators and Exhausts

5.6.1                 Adequate ventilation is to be provided throughout the vessel. The accommodation is to be protected from the entry of gas and/or vapour fumes from machinery, exhaust and fuel systems.

5.6.2                 Ventilators are to be of efficient construction and provided with permanently attached means of weathertight closure. Generally, ventilators serving any space below the freeboard deck or an enclosed superstructure should have a coaming of minimum height:

                        900mm in the forward quarter length of the vessel; and

                        760mm elsewhere.

For Short Range Yachts the required ventilator heights should be taken as half the above requirements.

5.6.3                 Ventilators should be kept as far inboard as practicable and the height above the deck of the ventilator opening should be sufficient to prevent the ingress of water when the vessel heels.

5.6.4                 The ventilation of spaces such as the machinery space, which must remain open, requires special attention with regard to the location and height of the ventilation openings above the deck, taking into account the effect of downflooding angle on stability standard. (See section 11.)

           The means of closure of ventilators serving the machinery space should be selected with regard to the fire protection and extinguishing arrangements provided in the machinery space.

5.6.5                 Engine exhaust outlets which penetrate the hull below the freeboard deck should be provided with means to prevent backflooding into the hull through a damaged exhaust system. For vessels operating on unrestricted service a positive means of closure should be provided. The system should be of equivalent construction to the hull on the outboard side of the closure. For Short Range Yachts, where the fitting of a positive closure is not practicable, the exhaust should be looped up above the waterline on the outboard side of the system, to a minimum height of 1000 mm, and be of equivalent construction to the hull.

5.7                    Air Pipes

5.7.1                 Air pipes serving fuel and other tanks should be of efficient construction and provided with permanently attached means of weathertight closure.   Means of closure may be omitted if it can be shown that the open end of an air pipe is afforded adequate protection by other structure(s) which will prevent the ingress of water.

5.7.2                 Where located on the weather deck, air pipes should be kept as far inboard as practicable and be fitted with a coaming of sufficient height to prevent inadvertent flooding. Generally, air pipes to tanks should have a minimum coaming height of:

                        760mm when sited on the freeboard deck; and

                        450mm elsewhere.

For Short Range Yachts the required ventilator heights should be taken as half the above requirements.

5.7.3                 Air pipes to fuel tanks should terminate at a height of not less than 760mm above either, the top of the filler pipe for a gravity filling tank or, the top of the overflow tank for a pressure filling tank.

5.8                    Scuppers, Sea Inlets and Discharges

           The standards of ICLL should be applied to every discharge led through the shell of the vessel as far as it is reasonable and practicable to do so, and in any case, all sea inlet and overboard discharges should be provided with efficient shut-off valves arranged in positions where they are readily accessible at all times.

5.9                    Materials for Valves and Associated Piping

5.9.1                 Valves which are fitted below the waterline should be of steel, bronze or other material having a similar resistance to impact and fire.

5.9.2                 The associated piping should, in areas as indicated above, be of steel, bronze, copper or other equivalent material.

5.9.3                 Where the use of plastic piping is proposed, it will be considered and full details of the type of piping, its intended location, and use, should be submitted for approval. Due regard should be paid to the IMO Fire Test Procedures Code.

5.9.4                 The use of flexible piping in any situation should be kept to a minimum compatible with the essential reason for its use.   Flexible piping and the means of joining it to its associated hard piping system should be approved as fit for the purpose by the Administration .

5.10                  General Equivalence

Where vessels cannot fully comply with the requirements of this section, equivalent arrangements may be considered by the Administration. Such proposals should take into account the following, although this should not be considered as an exhaustive list:-

•  Openings to be kept closed at sea

•  Enhanced Bilge Pumping capacity and additional bilge alarms

•  Compliance with damage stability if not already a requirement (see Section 11)

•  Provision of dorade boxes or baffle systems to prevent direct ingress of water

•  Alternative ventilation for use in bad weather

•  Consideration of downflooding angle and reduced risk of green sea loads, i.e. protected position

•  Enhanced survey inspection regime

•  Operational Limitations