Ceiling Hangers shall be fail safe and include a steel frame containing an AASHTO Bridge Bearing Quality LDS Rubber Element at the top and a nominal 1” deflection steel spring at the bottom. Springs shall be seated in an LDS 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 Cup and Element 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 30NCC for 11/2 x 1/2 channel, W30N for wire, or W30NCC for wire and channel. Submittals shall confirm AASHTO Quality and Dynamic Stiffness in addition to deflection.