2.7.1 A diving system should be equipped with
a main handling system to ensure safe transportation of the diving
bell between the work location and the surface compression chamber.
2.7.2 The handling system should be designed with
adequate safety factors considering the environmental and operating
conditions, including the dynamic loads which are encountered while
handling the diving bell through the air-water interface.
2.7.3 The handling system should enable smooth
and easily controllable handling of the diving bell.
2.7.4 The lowering of diving bells under normal
conditions should not be controlled by brakes, but by the drive system
of the winches.
2.7.5 If the energy supply to the handling system
fails, brakes should be engaged automatically.
2.7.6 In the event of single component failure
of the main handling system, an alternative means should be provided
whereby the bell can be returned to the surface compression chamber.
In addition, provisions should be made for emergency retrieval of
the bell if the main and alternative means fail. If this involves
buoyant ascent the bell should have sufficient stability to maintain
a substantially upright position and means should be provided to prevent
accidental release of the ballast weights.
2.7.7 Handling systems and mating devices should
enable easy and firm connection or disconnection of a diving bell
to a surface compression chamber, even under conditions where the
support ship or floating structure is rolling, pitching or listing
to predetermined degrees.
2.7.8 Where a power actuating system is used for
mating operations, an auxiliary power actuating system or an appropriate
means should be provided to connect a diving bell to a surface compression
chamber, in the event of failure of the normal power actuating system.