Ceiling Hangers shall be fail safe and include a steel frame containing a nominal 1” deflection steel spring seated in an AASHTO Bridge Bearing Quality Low Dynamic Stiffness Rubber Cup with a rubber bushing extending through the box to prevent metal to metal contact between the steel suspension rod and the frame. Dynamic Stiffness of the cup shall not exceed 1.4.

The ID of the bushing must allow a 30° swing from side to side before rod contact. Springs shall be factory precompressed to 70% of the assigned deflection. Hangers shall be Mason Industries 30CC for 11/2 x 1/2 channel, W30 for wire, W30CC for wire and 11/2 x 1/2 channel. Submittals shall confirm AASHTO Quality and Dynamic Stiffness in addition to deflection.