4.1.1 Shell doors
including bathing and watersport platforms, are generally to be fitted
with a sill not less than 600 mm above the design waterline. All openings
are to open into a watertight space with access into the yacht by
watertight doors capable of being operated from both sides. The outer
shell doors may be of a single or double leaf type with either hand
or hand and hydraulic operated door clips to ensure watertightness
when at sea. Any locking devices fitted are to `fail safe' in the
event of hydraulic failure. Provision is to be made for doors to be
closed and locked by hand in the event of hydraulic failure, see
Pt 3, Ch 4 Closing Arrangements and Outfit.
4.1.2 Watertight boundaries behind shell openings with a sill height below, or
less than 600 mm above, the design waterline are to have stress and deflection criteria
required for watertight bulkheads by Pt 6 Hull Construction in Steel,
Pt 7 Hull Construction in Aluminium
and Pt 8 Hull Construction in Composite of the rules for steel, aluminium alloy and composite respectively with a
design load according to side shell pressure, Ps as defined in Pt 5, Ch 2, 4.2 Combined hydrostatic and hydrodynamic pressure on the shell plating. Doors from this space providing internal access
are to have a sill height at least 600 mm above the design waterline. The effect of
flooding on stability and operational controls, and limitations on when and where
opening may be used, are to be considered. Provision is to be made for hydraulic doors
to be closed and locked by hand in the event of hydraulic failure, see
Pt 3, Ch 4 Closing Arrangements and Outfit.
4.1.3 Drainage
systems for the above shell openings are to be fitted with non-return
valves.
4.1.4 Transom
platforms are to be integral with the hull or be separate mechanically
secured components.
4.1.5 Integral
components are to have scantlings equivalent to the adjacent structure
with care taken to ensure continuity of strength with no hard spots.
4.1.6 Separate
mechanically secured components are to be of substantial construction
and securely fastened to the main structure ensuring bolting and sealing
arrangements are satisfactory with no hard spots.
4.1.7 Recesses
for passerelles, windlasses, platforms, cockpits etc. are to be watertight
and of equivalent strength to that of the surrounding hull and deck
structure with care being taken to ensure continuity of strength.
Electrical and hydraulic penetrations (where fitted) are to be through
watertight glands. Direct overboard discharges are to be fitted to
prevent any accumulation of water in the recess.