2 Hour Rated EM Feeders Per 700.10(D)

[ASG]

It's still not clear to me what is acceptable in high rise buildings per 700.10(D)

(2) Feeder-Circuit Wiring​

Feeder-circuit wiring shall meet one of the following conditions:

1. The cable or raceway is installed in spaces or areas that are fully protected by an approved automatic fire protection system.
2. The cable or raceway is protected by a listed electrical circuit protective system with a minimum 2-hour fire rating.
   Informational Note No. 1: See UL 1724, Fire Tests for Electrical Circuit Protection Systems, for one method of defining an electrical circuit protective system. The UL Guide Information for Electrical Circuit Integrity Systems (FHIT) contains information to identify the system and its installation limitations to maintain a minimum 2-hour fire-resistive rating and is available from the certification body.
3. The cable or raceway is a listed fire-resistive cable system with a minimum 2-hour fire rating.
   Informational Note No. 2: See UL 2196-2017, Standard for Fire Test for Circuit Integrity of Fire-Resistive Power, Instrumentation, Control and Data Cables, for one method of defining a fire-resistive cable system.
4. The cable or raceway is protected by a listed fire-rated assembly that has a minimum fire rating of 2 hours and contains only emergency circuits.
5. The cable or raceway is encased in a minimum of 50 mm (2 in.) of concrete.

The question is regarding item 1. If you are running horizontally in a hung ceiling or vertically in a shaft, is your cable or raceway in a space or area that is fully protected by an approved automatic fire protection system?

 

[Boingo1972]

The easy answer is......it depends. The sprinkler rule does not apply to fire pump circuits (or COPS), but does for other emergency circuits. If you're above a false ceiling, and the sprinkler heads are below that ceiling, you're not protected. Essentially the sprinkler head must be above the wires. Generally in high rises, you may end up using several methods to achieve the fire resistive rating. Typically those are sprinkled areas or 2 hour rated rooms/fire rated rooms the circuit serves. If using item 3 above, the fundamental rule is called the "fire zone". If you're in the fire zone (unprotected area) special wire and rules apply, but if outside the fire zone (protected area) you don't need the special wire and standard rules apply. Just remember, under 700.10(D) you only need to achieve one of those methods, so if part of the run is sprinkled and another section is within 2 hour rated rooms, those areas are protected.