Sprinklers and Shunt Trip Circuit Breakers
From: Elevator Safety Review Board
Robert A. Patterson, Deputy Director, Board Chair
Date: October 24, 2011
At the October 10, 2011 Board meeting, the topic of shunt trip breakers was discussed relative to elevator operation and safety. The board found no convincing evidence that shunt trip provides improved public safety, but did receive significant testimony to the contrary:
In some situations occupants can be trapped inside the elevator car, should the shunt trip breaker activate when the elevator car is between floors. When the shunt trip is activated fire departments are no longer able to utilize the elevator for rescue or fire operations. Elimination of shunt trip breakers will provide financial benefit to building owners by eliminating the continuing costs of maintaining/repairing the shunt trip feature in an operational state.
The Board determined to eliminate shunt trip circuit breakers subject to the following provisions:
When the elevator machine room is not constructed of non-combustible or limited combustible materials, (steel studs/joist and gypsum) it will be acceptable to provide an additional layer of 5/8” gypsum within the machine room in lieu of a non-combustible enclosure.
Where elevator shaft and machine room is constructed of non-combustible or limited combustible materials, the sprinkler head at the top of shaft must be removed and plugged, the heat detector disconnected from shunt trip breaker, and smoke detector removed. Where buildings have sprinkler protection, a sprinkler head shall be located no more than 24” above the pit floor.
Elevators having shunt trip in place shall have breakers removed or disconnected prior to January 1, 2015. This will allow both fire alarm and sprinkler vendors to complete work during annual inspection.
This action is similar to the State of Massachusetts elevator requirements approved in 2003.