Cable trays and busways at floor level or at slab penetrations shall have a waterstop no less than 50 mm in height. Sealing shall be tight and reliable, without visible cracks or. Where cables pass through shafts, walls, slabs, or enter electrical panels or cabinets, openings shall be tightly sealed with firestopping materials in accordance with design requirements. Process flow: reserved openings → busway installation → distribution box positioning and installation →. It is a little known fact that there are no proactive cable tray penetrations for trays to go through a fire barrier. In other words, the cable tray manufacturer did not go to UL or ETL and say “test this tray penetration for 2 hours, make the hole this size, and use these pillows, compressed this. Service penetration seals are passive fire protection systems designed to maintain the fire resistance of building element or section - wall or floor - where services such as cables, cable trays, pipes or ventilation ducts pass through them.
[PDF Version]