“RGS Single or Multiple Cable Rectangular Transits”, for use in approved A Class steel and aluminium bulkheads and/or decks and in Non-load bearing A-60 Sandwich Panel Bulkheads, as described in the attached DAD. (MCT Brattberg “RGS Single or Multiple Cable Rectangular Transits”)

Common issues

• Incorrect insert/module selection for the actual cable diameter, leaving gaps in the fire seal
• Cables added or removed after installation without re-validating against the transit's approved cable schedule (DAD)
• Deteriorated or missing frame gasket compromising fire/gas-tight integrity
• Under- or over-compression of insert modules from incorrect wedge/bolt torque
• Corrosion of the steel/aluminium frame at the bulkhead or deck penetration
• Unsealed spare/blank modules left in an otherwise sealed frame

Inspection checklist

• Visually check insert modules for cracking, displacement, or missing pieces
• Confirm the installed cable count/diameters match the transit's approved Design Appraisal Document (DAD)
• Check frame gasket condition and compression at the bulkhead/deck interface
• Verify wedge/tensioning bolts are torqued per maker's instruction
• Check for corrosion at the frame-to-structure weld or bolted connection
• Confirm blank modules are fitted and sealed where no cable is present
• Check for any unauthorised cable additions since the last survey

Service intervals

Typical intervals for this design class, not the manufacturer’s figures for your model. The manufacturer’s manual is binding.

Critical spares

• Blank/spare insert modules matching the frame's module size
• Frame gasket
• Wedge/tensioning bolt set

Safety

• An incorrectly filled or damaged transit compromises the fire (and sometimes watertight/gastight) integrity of the A-class division it penetrates
• Unauthorised cable additions without re-sealing are a recognised source of fire integrity failures found at survey
• Work on the transit should be coordinated with a hot-work/fire watch procedure if adjacent to flammable spaces

Class survey

Cable transits through A-class divisions are checked against their type-approval certificate and the vessel's Design Appraisal Document (DAD) at fire safety surveys; any cable added after the original installation must be verified against the approved schedule or the transit's fire rating cannot be assumed valid.

Estimated lifetime: Not measured in running hours - the transit frame typically lasts the life of the structure it is fitted to, with the gasket and insert modules renewed on a condition basis, particularly after cable modifications.