Fans

Structure-Borne Vibration

Problem: Suspended fans can transmit vibration through the rod hangers into the structure that can create serious noise problems.

Solution: Spring hangers. If space will allow, SHRB with neoprene element under spring and separating structural attachment is ideal.

Seismic Requirements

Problem: Horizontal and vertical forces applied at the center-of-gravity of the unit require proper design of the attachment of the unit and/or vibration isolators to the structure.

Solution: Properly designed cable or solid restraint system to be installed. Cable system required when unit is isolated.

Problem: Net uplift forces on units with spring hangers can cause damage and lead to failure of spring hangers.

Solution: Spring hangers with up stop limit washers to be used.

Problem: Forces are determined by a number of factors including: project location, site class, risk category, component importance factor and equipment location equipment relative to the overall height of the building.

Solution: Certified anchorage calculations must be submitted to verify loading conditions are met for each piece of equipment.

Problem: Structural attachment may have limited capacity or be difficult to attach.

Solution: Custom designed restraints to be used for various structural types, including BulletClamp. Other difficult structures to be noted: trusses, pan deck, thin concrete deck.