Elevator shafts with Dry Agent Supression and Shut Trips.

[Dp_saint]

Question with regards to if a shut trip is required on a 2 floor elevator in an unoccupied storage facility that is protected by a dry agent suppression system. I?ve always understood a shut-trip is to shut power down prior to the wet type sprinkler head going off in the shaft or machine room. This makes sense because of the fear of electrocution and the erratic or nonoperation of the elevator when circuit get wet. However, with the dry agent system these issues are eliminated. If fact I would think that under no circumstance would you want the elevator to shut-down and allow even the slightest possibility of someone being trapped inside the car during a dry agent release event.

Electrician has put the bug in the ear of the local code official that a shunt trip is required. Does anyone know if there is a section of the code that applies to dry agent systems in elevator shafts.

Thanks,

 

[steve66]

As far as I know, a shunt trip is only required for a wet fire suppression system, so power can be tripped before the application of water.

Does the dry system really cover the elevator shaft too? If so, I think you have it right - don't want to leave someone stuck in the car while the space is filled with a chemical (even though the elevator cars always have a vent fan). Elevator recall may still be needed.

I've been using a new exception in NFPA 13 to eliminate sprinklers in elevator shafts and machine rooms for traction elevators. No fire suppression definitely eliminates the need for a shunt trip.