Life Safety 101- Section 7.9.2.3

alixenos

Member
Location
Florida
Occupation
Electrical Design Engineer
Hello,

In section 9.1.2 of the life safety code (Electrical Systems) there is a mention to section 7.9.2.3 for emergency lighting. Anyone one familiar with this section? I don't quite understand 7.9.2.3(2) and how to incorporate it into the design.

Here is the section
7.9.2.3 The emergency lighting system shall be arranged to provide
the required illumination automatically in the event of any interruption
of normal lighting due to any of the following:
(1) Failure of a public utility or other outside electrical power
supply
(2) Opening of a circuit breaker or fuse
(3) Manual act(s), including accidental opening of a switch controlling
normal lighting facilities.

If I'm providing one circuit to a space coming from an emergency panel, is that not enough?

Thanks.
 
101 is not typically an adopted code. Egress and exit lighting / signage requirements are found in the adopted building code. If it were the IBC, 1008 covers egress and 1013 covers exit signage.
 
Understand that the purpose emergency lighting is to illuminate an area for a period of time (30 minutes?) to allow personnel to safely evacuate the area. It is not meant to be a backup lighting system. Adding multiple supply circuits does nothing if all electrical power is lost. A second power source - ie a generator - might be your best option. Of course, this means proper ignition of the generator and switching into existing circuitry.
 
Understand that the purpose emergency lighting is to illuminate an area for a period of time (30 minutes?) to allow personnel to safely evacuate the area. It is not meant to be a backup lighting system. Adding multiple supply circuits does nothing if all electrical power is lost. A second power source - ie a generator - might be your best option. Of course, this means proper ignition of the generator and switching into existing circuitry.
I am supplying the lighting circuits from an emergency panel. The above code I think discusses the possibility of opening of a circuit breaker that will cause the lighting to lose power ( normal source and/or generator still exit).
If Im understanding it correctly, I need to supply the lighting from two different emergency panels, if one breaker trips the other wont.
 
I am supplying the lighting circuits from an emergency panel. The above code I think discusses the possibility of opening of a circuit breaker that will cause the lighting to lose power ( normal source and/or generator still exit).
If Im understanding it correctly, I need to supply the lighting from two different emergency panels, if one breaker trips the other wont.
Depends on what the emergency Panel is fed from. If it is from a valid NEC Article 700 source, then one circuit is ok, and must be kept physically separated from non-emergency circuits.
 
Yes its fed from a panel compliant with NEC 700.
If that panel MCB or branch circuit breaker trips, then the illumination will lose both sources of energy ( Normal and Generator)
How can such possibility be addressed if we provide one circuit only?
 
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