fandi
Senior Member
- Location
- Los Angeles
Hello All.
The question is for egress lighting (not exit signs) for a small retail space. I don't see NEC 700.15 thru 700.19 talks about the requirement to have two sources for emergency lighting. It only says emergency source is required for emergency lighting.
I'm not sure it's covered in Building Code but I saw this old thread since 2005 but I don't have the latest version of NFPA 101 Life Safety code so I can't tell:
A.7.9.2.2
Where approved by the authority having jurisdiction, this requirement is permitted to be met by means such as the following.
(a) Two separate electric lighting systems with independent wiring, each adequate alone to provide the specified lighting. One such system is permitted to be supplied from an outside source such as a public utility service and the other from an electric generator on the premises driven by an independent source of power. Both sources of illumination should be in regular simultaneous operation whenever the building is occupied during periods of darkness.
(b) An electric circuit or circuits used only for means of egress illumination, with two independent electric sources arranged so that, on the failure of one, the other will automatically and immediately operate. One such source is permitted to be a connection from a public utility or similar outside power source and the other an approved storage battery with suitable provision to keep it automatically charged. Such a battery should be provided with automatic controls that, after operation of the battery due to failure of the primary power source or to turn-off the primary electric source for the lights, the battery will be shut off after its specified period of operation and will be automatically recharged and ready for further service when the primary current source is turned on again.
(c) Electric battery-operated emergency lighting systems complying with the provisions of 7.9.2.2 and operating on a separate circuit and at a voltage different from that of the primary light can be used where permitted. (See NFPA 70, National Electrical Code ?.)
These requirements are not intended to prohibit the connection of a feeder serving exit lighting and similar emergency functions ahead of the service disconnecting means, but such provision does not constitute an acceptable alternate source of power. Such a connection furnishes only supplementary protection for emergency electrical functions, particularly where intended to allow the fire department to open the main disconnect without hampering exit activities. Provision should be made to alert the fire department that certain power and lighting is fed by an emergency generator and will continue operation after the service disconnect is opened.
Where emergency lighting is provided by automatic transfer between normal power service and an emergency generator, it is the intent to prohibit the installation, for any reason, of a single switch that can interrupt both energy sources.
Please let me know if NEC requires two sources of power or if you could confirm that the latest NFPA 101 Life Safety code states the same thing as above A.7.9.2.2.
Thanks,
The question is for egress lighting (not exit signs) for a small retail space. I don't see NEC 700.15 thru 700.19 talks about the requirement to have two sources for emergency lighting. It only says emergency source is required for emergency lighting.
I'm not sure it's covered in Building Code but I saw this old thread since 2005 but I don't have the latest version of NFPA 101 Life Safety code so I can't tell:
Emergency Lighting
When a structure is required by the building code to have emergency lighting and exit signs and there is an emergency generator tied into the normal power system, do the emergency fixtures and exit signs need to have a battery back-up? If so, please provide the code reference and the text...
forums.mikeholt.com
A.7.9.2.2
Where approved by the authority having jurisdiction, this requirement is permitted to be met by means such as the following.
(a) Two separate electric lighting systems with independent wiring, each adequate alone to provide the specified lighting. One such system is permitted to be supplied from an outside source such as a public utility service and the other from an electric generator on the premises driven by an independent source of power. Both sources of illumination should be in regular simultaneous operation whenever the building is occupied during periods of darkness.
(b) An electric circuit or circuits used only for means of egress illumination, with two independent electric sources arranged so that, on the failure of one, the other will automatically and immediately operate. One such source is permitted to be a connection from a public utility or similar outside power source and the other an approved storage battery with suitable provision to keep it automatically charged. Such a battery should be provided with automatic controls that, after operation of the battery due to failure of the primary power source or to turn-off the primary electric source for the lights, the battery will be shut off after its specified period of operation and will be automatically recharged and ready for further service when the primary current source is turned on again.
(c) Electric battery-operated emergency lighting systems complying with the provisions of 7.9.2.2 and operating on a separate circuit and at a voltage different from that of the primary light can be used where permitted. (See NFPA 70, National Electrical Code ?.)
These requirements are not intended to prohibit the connection of a feeder serving exit lighting and similar emergency functions ahead of the service disconnecting means, but such provision does not constitute an acceptable alternate source of power. Such a connection furnishes only supplementary protection for emergency electrical functions, particularly where intended to allow the fire department to open the main disconnect without hampering exit activities. Provision should be made to alert the fire department that certain power and lighting is fed by an emergency generator and will continue operation after the service disconnect is opened.
Where emergency lighting is provided by automatic transfer between normal power service and an emergency generator, it is the intent to prohibit the installation, for any reason, of a single switch that can interrupt both energy sources.
Please let me know if NEC requires two sources of power or if you could confirm that the latest NFPA 101 Life Safety code states the same thing as above A.7.9.2.2.
Thanks,
