Section 10 Miscellaneous openings

10.1.1 The requirements of Pt 3, Ch 11, 6 Miscellaneous openings are to be complied with.

10.2.1 Where the main vehicle deck is enclosed, all companionways and openings in the deck which lead to spaces below are generally to be protected by steel doors or hatch covers. Approved fire doors may be accepted in lieu of steel doors. The sills or coamings are to be not less than 230 mm above the main vehicle deck, with the exception of those leading to machinery spaces which are to have sills or coamings not less than 380 mm. Exceptionally, when such openings are to be kept closed at sea, sills or coamings may be reduced in height, provided that the sealing arrangements are adequate. In such cases, the doors or hatch covers are to be secured weathertight by gaskets and a sufficient number of clamping devices. Such items as portable plates in the main vehicle deck arranged for the removal of machinery parts, etc. may be arranged flush with the deck, provided they are secured by gaskets and closely spaced bolts at a pitch not exceeding five diameters.

10.2.2 Scuppers from vehicle or cargo spaces above the bulkhead deck fitted with an approved fixed pressure water spray fire-extinguishing system are to be led directly overboard and are to be fitted with means of preventing water from passing inboard in accordance with Pt 3, Ch 12, 4.2 Closing appliances.

10.2.3 Inboard draining scuppers do not require valves but are to be led to suitable drain tanks (not engine room or hold bilges) and the capacity of the tanks is to be sufficient to hold approximately 20 minutes of drenching water. The arrangements for emptying these tanks are to be approved and suitable high level alarms provided.

10.2.4 A drainage system is to be arranged in the area between bow door and ramp, or where no ramp is fitted, between the bow door and inner door. The system is to be equipped with an audible and visual alarm function to the navigation bridge being set off when the water levels in these areas exceed 0,5 m or the high water level alarm, whichever is the lesser.

10.2.5 The drainage arrangement for each area is to have sufficient capacity to prevent accumulation of water in case of leakage. Scuppers are to be provided on both sides of the ship with a diameter not less than 50 mm and in accordance with Pt 3, Ch 12, 4 Scuppers and sanitary discharges. Alternatively, a bilge suction should be provided.

10.2.6 If the main vehicle deck is not totally enclosed, scuppers or freeing ports are to be provided consistent with the requirements of Pt 3, Ch 8, 5.3 Freeing arrangements.

10.2.7 Air pipes from cofferdams or void spaces may terminate in the enclosed 'tween deck space on the main vehicle deck provided the space is adequately ventilated and the air pipes are provided with weathertight closing appliances.

10.2.8 Between the bow door and the inner door a television surveillance system is to be fitted with a monitor on the navigation bridge and in the engine control room. The system must monitor the position of doors and a sufficient number of their securing devices. Special consideration is to be given for lighting and contrasting colour of objects under surveillance, see also Pt 4, Ch 2, 8.5 Arrangements for the closing, securing and supporting of doors 8.5.7.

10.3.1 On windows in the second tier and higher above the freeboard deck, a glazing equivalent may be fitted in lieu of deadlights/storm covers. The thicknesses and arrangements are to be acceptable to the National Authority with whom the ship is registered and/or by the Administration within whose territorial jurisdiction the ship is intended to operate. For arrangements of glazing acceptable to LR, see Table 2.10.1 Acceptable arrangements of glazing in lieu of portable storm covers/deadlights. Alternative arrangement of glazing in lieu of deadlights/storm covers may be accepted provided details are submitted for consideration.

10.3.2 For passenger ships the design pressure, H _d, on windows is to be taken as given in Table 2.10.2 Design pressure, H_d, on windows, or an equivalent National or Internationally Recognised Standard.

10.3.3 The thickness, t _o, of toughened safety glass is to be taken as given in Table 2.10.3 Thickness of toughened glass.

10.3.4 Toughened safety glass of laminated construction will also be accepted, provided the requirements of Pt 3, Ch 11, 6.5 Side scuttles, windows and skylights 6.5.29 are complied with.

Table 2.10.1 Acceptable arrangements of glazing in lieu of portable storm covers/deadlights

In lieu of portable storm covers	In lieu of deadlights and storm covers
Symbols
t 0 = minimum thickness of toughened glass as calculated in Table 2.10.3 Thickness of toughened glass

Table 2.10.2 Design pressure, H_d, on windows

Window location	Design pressure head H d in metres
Between the design waterline and a point Z 1,5 m above the waterline	Per BS MA 25: 1973
Between a point Z 1,5 m above the waterline and the deck immediately above (at Z d1,5)	1,5
Over the next 2 'tween deck heights
For subsequent decks to the top of the navigation bridge	0,25 sides and aft ends 0,75 house fronts
From the top of the navigation bridge to the uppermost deck, for house fronts	0,75 at top of navigation bridge 0 at uppermost continuous deck, with linear variation between, but not less than 0,25
From the top of the navigation bridge to the uppermost deck, at sides and aft ends	0,25
Symbols
f w = 1,25 in way of sides and ends of superstructures = 0,75 in way of house fronts Z 1,5 = the vertical location in metres above the waterline at which the BS MA:25 pressure as given in Annex E of BS MA:25 (1973) is 1,5 t/m2 Z d1,5 = the vertical location in metres of the deck at which the pressure is 1,5 t/m2 from Table 2.10.1 Acceptable arrangements of glazing in lieu of portable storm covers/deadlights Z w = the vertical location in metres above the waterline to the point under consideration H t1 + H t2 = sum of the appropriate 'tween deck heights in metres

Table 2.10.3 Thickness of toughened glass

Window type	Thickness, t o, in mm
Rectangular
Circular
Semi-circular
Symbols
b = length of shorter side of window, in mm H d = design pressure head, in metres, as calculated in Table 2.10.2 Design pressure, Hd, on windows β = 0,54A R – 0,078A R 2 – 0,17 for A R ≤ 3 = 0,75 for A R > 3 A R = aspect ratio of window, in mm = a/b a = length of longer side of window, in mm r = the radius of the window, in mm

10.4.1  Application. The testing requirements contained in this Section are for all exterior window designs on all tiers for passenger ships regardless of length. The testing is to be carried out for characteristic window sizes (largest, smallest) and forms (circular, semicircular and rectangular) for each passenger ship. Window designs which are not covered by Type Approval Certification will require prototype testing in order to confirm structural integrity and weather or water tightness as required. Tests are to be carried out to the satisfaction of the Surveyor.

10.4.2  Water tightness. hydrostatic test is to be carried out in order to examine the water tightness of windows. This is carried out by applying the design pressure head H _d, as calculated in Pt 4, Ch 2, 10.3 Strength assessment of windows in large passenger ships, to the external face of the window and maintained at this level for at least 15 minutes.

10.4.3  Structural testing. A hydrostatic test is to be carried out in order to examine the capability of the frame, mullions and the retaining arrangement for the glazing. This is carried out by applying a test pressure of 4H_d (H_d as calculated in Pt 4, Ch 2, 10.3 Strength assessment of windows in large passenger ships for windows) to the external face of the window, utilising an aluminium alloy plate of appropriate temper and thickness to simulate the flexural response in lieu of the glazing. A full-scale test with actual glazing in place may be acceptable provided that the stresses induced are within allowable limits. Details of the calculations made and testing procedures are to be submitted for review prior to the test. Alternative means of demonstrating adequacy of the frame, mullions and the retaining arrangement for the glazing may be specially considered.

10.4.4 Equivalent proposals for testing will be considered. Where alternative testing procedures are proposed, these are to be agreed with LR before commencement.

10.4.5  Chemically toughened glass.

1. Chemically toughened glass may be used in lieu of thermally toughened glass provided it can be demonstrated the strength of the arrangement is at least equivalent in strength to that of thermally toughened glass.

2. The glazing system is to be of laminated construction.

3. Method of testing will be specially considered.

10.4.6 The overlap between glazing and the retaining frame is not to be less than 12 mm.

10.5.1 The section modulus of mullions is not to be less than:

where

a	=	see Table 2.10.4 Mullion arrangements
b	=	see Table 2.10.4 Mullion arrangements
r	=	see Table 2.10.4 Mullion arrangements
	=	a for rectangular windows
	=	2r for semi-circular windows
H d	=	design pressure head, in metres, as calculated in Pt 4, Ch 2, 10.3 Strength assessment of windows in large passenger ships 10.3.2
A m	=	ab for rectangular windows
	=	1,22r 2 for semi-circular windows
k	=	as defined in Pt 4, Ch 2, 1.5 Symbols 1.5.1.

Table 2.10.4 Mullion arrangements

Rectangular windows	Semi-circular windows
Symbols
a = dimension parallel to mullion, in mm b = length of shorter side of window, in mm r = radius of the window, in mm

10.6.1 A ‘bonded window’ or ‘bonded side scuttle’ is one in which the glazing material is secured in its frame from outside of the ship by glue or other adhesive material. No mechanical fixing is provided for the glazing. Bonded windows and side scuttles are to comply with the requirements of Pt 4, Ch 2, 10 Miscellaneous openings. Proposals to secure glazing from the inside of the ship are to be specially considered using the requirements in this Section as a basis. It should be noted that bonding from the inside is not recommended and where it is proposed, further testing will be required. Non-load bearing secondary bonded glazing, e.g. glazing to improve thermal insulation, is not required to comply with the requirements of this sub- Section.

10.6.2 The adhesive is to be flexible enough to support the glazing without holding it firm. The glue strip is to be elastic, with width and thickness designed to allow the glazing to move in both directions in the plane of the glazing without undue forces on the bonding or the substrate. The glass is to be free to settle under-load and not to be forced to follow deflections in the supporting structure. If substantial racking of the glazing opening under-load is expected, the bonding is to be designed to accommodate such deflections.

10.6.3 Bonded windows and side scuttles may be considered as acceptable, in general, depending on their position, size of vessel and applicable statutory requirements, noting the distinction between glazing and the frame, which may have different requirements.

10.6.4 Bonded windows are not permitted in galley areas, including glazing in galley doors (internal or external). They are not permitted on escape routes and evacuation routes where a fire rating is required. The fire integrity of bulkheads is not to be impaired.

10.6.5 Bonded windows and side scuttles are not acceptable on fire-fighting vessels, i.e. those with a fire-fighting notation.

10.6.6 The failure of laminated glass is considered to pose a lower risk to safety than that of single pane glass. In the event of breaking, laminated glass more readily holds together and tends not to break up into large sharp pieces. Therefore, in general, laminated glazing is preferred. When laminated glass is used, the sealant is to be compatible with the interlayer. Lamination thickness is to be in accordance with Pt 3, Ch 11, 6.5 Side scuttles, windows and skylights 6.5.29. Special consideration will be given to single pane toughened safety glass.

10.6.7 The durability of the adhesive and the sealant in the long term marine environment is to be considered in the approval process. Adhesive is to be approved in accordance with Ch 14, 2.15 Adhesive and sealant materials of the Rules for Materials. The adhesive bead is to be resistant to or protected from UV radiation, either by an optically dense area at the edges of the glazing or by overlapping trim or UV shielding tape. The adhesive bead is to be resistant to or protected from fungal attack. Arrangements are to be in accordance with the adhesive manufacturer’s published guidelines and relevant LR Rules.

10.6.8 The edges of the bonding recess are to be rounded to facilitate the application of the sealant without air entrapment. The width of the gap between the flange and the glazing is to be large enough to accommodate the movement of the glazing as a result of hull deflection and thermal expansion, see Figure 2.10.1 Gap width between flange and window, bonded from outside of the ship. Recommended gap widths for bonded windows are to be taken as:

Figure 2.10.1 Gap width between flange and window, bonded from outside of the ship

10.6.9 The minimum adhesive width and thickness are to be in accordance with the adhesive manufacturer’s published guidelines.