NFPA# 101 Life Safety Code
National Fire Protection Association # 101 Life Safety Code requires all emergency and exit lights to be clearly illuminating at all times. In the event of a power outage it is required for all emergency and exit lighting units be powered off a battery backup for a minimum of 90 minutes.
NFPA # 101 mandates exit routes including stairs, aisles, corridors, and ramps all have emergency lighting.
Emergency lighting must emit at least 1 foot candle of light at any point in the building and 0.1 foot candle of light along the emergency path of exit at floor level.
NFPA 101 Statutes
7.9.1.2 For the purposes of 7.9.1.1, exit access shall include only designated stairs, aisles, corridors, ramps, escalators, and passageways leading to an exit. For the purposes of 7.9.1.1, exit discharge shall include only designated stairs, ramps, aisles, walkways, and escalators leading to a public way
7.9.2.1* Emergency illumination shall be provided for not less than 1 1/2 hours in the event of failure of normal lighting. Emergency lighting facilities shall be arranged to provide initial illumination that is not less than an average of 1 ftcandle (10.8 lux) and, at any point, not less than 0.1 ft-candle (1.1 lux), measured along the path of egress at floor level. Illumination levels shall be permitted to decline to not less than an average of 0.6 ft candle (6.5 lux) and, at any point, not less than 0.06 ft-candle (.65 lux) at the end of the 1 1/2 hours. A maximum-to minimum illumination uniformity ratio of 40 to 1 shall not be exceeded
7.9.3.1.1 Testing of required emergency lighting systems shall be permitted to be conducted as follows: (1) Functional testing shall be conducted monthly with a minimum of three weeks and a maximum of 5 weeks between tests, for not less than 30 seconds, except as otherwise permitted by 7.9.3.1.1 (2). (2)* The test interval shall be permitted to be extended beyond 30 days with the approval of the authority having jurisdiction. (3) Functional testing shall be conducted annually for a minimum of 1½ hours if the emergency lighting system is battery powered. (4) The emergency lighting equipment shall be fully operational for the duration of the tests required by 7.9.3.1.1 (1) and (3). (5) Written records of visual inspections and tests shall be kept by the owner for inspection by the authority having jurisdiction.