5.5 Windows

  5.5.1 Windows should be of strength appropriate to their location in the vessel and meet the requirements of BSMA 25 or equivalent 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 windows should meet the requirements of 14A and 14B.

  5.5.2 For all vessels 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. Additionally, as a minimum, calculated thicknesses should meet Classification Society requirements for pleasure vessels or yachts. For Short Range Yachts, test pressures may be reduced to 2.5 times the derived design pressure.

  5.5.3 When using BSMA 25 or equivalent, the following minimum design heads may be assumed when determining design head pressure.

  5.5.4 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.

  5.5.5 Where chemically toughened safety glass is used, windows are to be of the laminated type, the minimum depth of chemical toughening to be 30 microns on exposed faces. Regular inspections of the windows, with particular reference to the surface condition, should form part of the operational procedures and annual survey by a Classification Society.

  5.5.6 Windows should not be fitted in the main hull below the level of the freeboard deck.

  5.5.7 For all vessels, other than Short Range Yachts, storm shutters (strong protective covers with fittings) 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.

  5.5.7.1 Where windows are of laminated construction and their equivalent toughened safety glass thickness exceeds the requirements of the applied standard specified in 5.5.1 by a minimum of 30%, storm shutters need not be carried, but a blanking plate(s) is to be provided (a plate capable of being fixed over a broken window) so that any window opening may be sealed in the event of glass failure. For windows subject to test in accordance with 5.5.2 only blanking plates are required.

When storm shutters are interchangeable port and starboard, a minimum of 50% of each size should be provided.

  5.5.8 Side and front windows to the navigating position should not be constructed of polarised or tinted glass. (See Section 18.2.3)