In most facilities, the largest part of emergency illumination lights the pathways and exits that lead out of the building—the egress paths. Its intent is to facilitate evacuation of the facility, particularly in the event of a fire, and to reduce the tendency of occupants to panic under stress, and in the dark.
Because the performance of emergency lighting is directly related to life safety, code officials are notoriously demanding of strict compliance in its design and installation.
Differing interpretations about emergency lighting requirements easily can lead to a costly delay of occupancy. For the purposes of this article, emergency lighting refers to lighting equipment that is specifically identified as such in one of the codes, with limited exception. Certain lighting that must illuminate under emergency conditions in health care facilities, but is not technically defined as emergency lighting, is addressed separately.
Code-enforcement agencies may adopt these codes, or other codes, and may enforce other editions. Provisions of the various codes sometimes differ regarding similar sets of requirements. Designers should verify the codes and editions in force, and consult authorities having jurisdiction AHJ regarding their interpretations of ambiguous or conflicting requirements, before design commences.
It calls for egress lighting for nearly all occupancies, with limited exceptions for agricultural and livestock buildings, dwelling units in institutional occupancies and most residential occupancies, and aisles in assembly occupancies. Egress lighting must remain active whenever the building is occupied IBC When that supply fails, an emergency power supply must illuminate specific areas, particularly pathways that lead to exits, the exits themselves, and exit discharges.
The IBC allows for a number of options for the form of the emergency power system. It may be an onsite generator, a battery-powered system, or a distributed set of batteries attached to individual luminaires.
NFPA provides a similar set of requirements. Emergency lighting is required for egress in all occupancies addressed by the code, with the exception of one- and two-family dwellings and rooming houses. The IBC generally applies to new construction and renovation projects. Its provisions are not normally enforced retroactively on existing buildings, except where the AHJ determines that public safety is compromised by existing conditions IBC NFPA is enforceable on existing buildings and includes separate requirements for existing and new facilities for each type of occupancy that it addresses.
For emergency lighting, NFPA requirements for new and existing facilities are substantially identical, with a few exceptions. Certain existing worship venues, for example, are permitted to operate without emergency lighting under NFPA , while similar new facilities are required to provide it NFPA NFPA requires emergency egress lighting in exit accesses, at exits, and at exit discharges.
In a typical design project, these building components are designated by the architect and indicated in the life safety plans. When those plans are not available early in the design process, the designer can get very close to compliant egress lighting by providing emergency lighting in corridors, stairways, at exits, and immediately outside exits.
The IBC specifically requires emergency lighting in certain spaces not used for egress: electrical rooms, fire command centers, fire pump rooms, and generator rooms. No special performance characteristics are specified for these areas. A minimal interpretation would be that these areas require egress illumination.
That solution might be suitable for utility spaces, where emergency light would provide wayfinding and be supplemented by portable battery-powered lamps. However, egress-level lighting would certainly be inadequate for a fire command center. Exit signs are required along the egress path, at doorways leading to an egress path, and at exits, placed to ensure that an exit sign is visible from no more than ft or the listed viewing distance of the exit sign IBC This requirement is echoed in NFPA 7.
NFPA 7. This requirement also is in NFPA NFPA 99 calls for battery-powered lighting in locations where deep sedation or general anesthesia is used, with lighting levels sufficient to terminate procedures in the room.
These battery lighting units are required to operate for at least 30 minutes NFPA 99 6. The purpose of these battery-powered lights is to ensure that a surgeon wielding a scalpel will not be left in total darkness should normal power fail during a procedure, and to provide minimal lighting for terminating a procedure should the standby lighting also fail.
Technically, these lights are not emergency lights, as there is no emergency electrical system defined for health care facilities. The NEC allows these lighting units to be connected to the critical branch rather than the life safety branch. General performance requirements for emergency egress illumination are shown in IBC Illumination requirements are identical in these two codes.
The egress path must be illuminated at an average level of 1 fc, with a minimum level of 0. Emergency lighting must remain illuminated for at least 90 minutes. Illumination levels are allowed to decline to an average of 0.
That requirement translates to restoration of power to emergency lighting within 10 seconds after loss of normal power, for a duration of 1.
Emergency illumination requirements for stairways are subject to interpretation under NFPA Section 7. For example, 7. A reasonable interpretation, then, is that Section 7. However, some AHJs have enforced the fc rule on emergency lighting in stairways. Class C structures, which is defined as a store not more than 3, square feet and one story only, are not required to have emergency lighting according to the requirements found in chapters According to chapter Chapter All storage occupancies need emergency lighting except for spaces occupied only during daylight hours with windows arranged to provide the required level of illumination on all portions of the means of egress during such hours, if approved by the Authority Having Jurisdiction , according to chapter Again, it is important that you always discuss all code interpretation with your Authority Having Jurisdiction.
With a free hazard analysis of your building, Koorsen can provide the right services to keep your emergency and exit lights operating properly and according to code. Disclaimer: The information in this article is for informational purposes only. It does not constitute professional advice.
The user of this article or the product s is responsible for verifying the information's accuracy from all available sources, including the product manufacturer. The authority having jurisdiction should be contacted for code interpretations. Daycare Occupancies Chapters However, there are three exempt structures where emergency lighting is not needed, including:.
If your buildings do not fall into these exemptions, you must provide a safe way for people to leave using emergency lighting. Some common places emergency or exit lighting should be installed include:. Since people rely on emergency and exit lights to safely guide them out of dangerous situations, it is important to ensure the system is functioning properly by testing it periodically. In fact, without following necessary testing guidelines, you are not only risking building occupants but also violating life safety codes intended to prevent emergency lighting failure.
The NFPA permits three options for conducting emergency light testing, including:. Regardless of the option used for testing your emergency lighting system, it must include a second test every month and a minute test every year. Besides knowing where to install emergency and exit lights, proper installation requirements must also be adhered to. This includes ensuring the lights are appropriately aimed to light the walkway and correctly spaced to avoid overly bright or dark spots.
Emergency lighting and exit signs must light up in the event of a power outage, which often requires the need for a reliable battery backup.
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