5-9.1 General.
5-9.1.1 Emergency lighting facilities for means of egress shall be provided in accordance with this section for every building or structure where required in Chapters 8 through 30. For the purposes of this requirement, exit access shall include only designated stairs, aisles, corridors, ramps, escalators, and passageways leading to an exit.

5-9.1.2 Where maintenance of illumination depends upon changing from one energy source to another, there shall be no appreciable interruption of illumination during the changeover.

5-9.2 Performance of System.
5-9.2.1* Emergency illumination shall be provided for a period of 1-1/2 hours in the event of failure of normal lighting. Emergency lighting facilities shall be arranged to provide initial illumination that is no less than an average of 1 footcandle (10 lx) and a minimum at any point of .1 footcandle (1 lx) measured along the path of egress at floor level. Illumination levels may decline to .6 footcandle (6 lx) average and a minimum at any point of .06 footcandle (.6 lx) at the end of the emergency illumination lighting time duration. A maximum to minimum illumination uniformity ratio of 40 to 1 shall not be exceeded.

5-9.2.2* The emergency lighting system shall be so arranged as to provide the required illumination automatically in the event of any interruption of normal lighting, such as any failure of public utility or other outside electrical power supply, opening of a circuit breaker or fuse, or any manual act(s), including accidental opening of a switch controlling normal lighting facilities.

5-9.2.4 Battery operated emergency lights shall use only reliable types of rechargeable batteries provided with suitable facilities for maintaining them in properly charged condition. Batteries used in such lights or units shall be approved for their intended use and shall comply with NFPA 70, National Electrical Code.®

5-9.2.5 The emergency lighting system shall be either continuously in operation or capable of repeated automatic operation without manual intervention.

5-9.3 Testing and Maintenance (See Section 31-1) 31-1.3.1 Whenever or wherever any device, equipment, [or] system...is required for compliance with the provisions of this Code, such device, equipment, [or] system...shall thereafter be permanently maintained unless the Code exempts such maintenance.

31-1.3.4 Any equipment requiring test or periodic operation to assure its maintenance shall be tested or operated as specified elsewhere in this Code or as directed by the authority having jurisdiction.

31-1.3.5 Systems shall be under the supervision of a responsible person who shall ensure that proper tests are made at specified intervals and have general charge of all alterations and additions.

31-1.3.7 Periodic Testing of Emergency Lighting Equipment.
A functional test shall be conducted on every required emergency lighting system at 30-day intervals for a minimum of 30 seconds. An annual test shall be conducted for the 1-1/2 hour duration. Equipment shall be fully operational for the duration of the test. Written records of testing shall be kept by the owner for inspection by the authority having jurisdiction.

5-10.1 General
5-10.1.2* Exits shall be marked by an approved sign readily visible from any direction of exit access.

Exception: Main exterior exit doors that obviously and clearly are identifiable as exits.

5-10.1.4 Access to exits shall be marked by approved readily visible signs in all cases where the exit or way to reach it is not readily apparent to the occupants. Sign placement shall be such that no point in the exit access is more than 100 ft from the nearest visible sign.

Exception: Signs in existing buildings need not meet the 100-ft distance requirement.

5-10.1.5* Where floor proximity exit signs are specifically required in Chapters 8 through 30, exit signs shall be placed near the floor level in addition to those signs required for doors or corridors by 5-10.1.2 and 5-10.1.3. These signs shall be sized and illuminated in accordance with he requirements of 5-10.2 and 5-10.3. The bottom of the sign shall be not less than 6 in. nor more than 8 in. above the floor. For exit doors, the sign shall be mounted on the door or adjacent to the door with the closest edge of the sign within 4 in. of the door frame.

5-10.2* Size of Signs. Every sign required by Section 5-10 shall have the word "EXIT" or other appropriate wording in plainly legible letters not less than 6 in. (15.2 cm) high with the principal strokes of letters not less than 3/4 in. (1.9 cm) wide. The word "EXIT" shall have letters of a width not less than 2 in. (5 cm) except the letter "I" and the minimum spacing between letters shall be not less than 3/8 in. (1 cm). Signs larger than the minimum established in this paragraph shall have letter widths, strokes, and spacing in proportion to their height.

5-10.3 Illumination of Signs.
5-10.3.1* Every sign required by 5-10.1.2 or 5-10.3 shall be suitably illuminated by a reliable light source. Externally and internally illuminated signs shall be visible in both the normal and emergency lighting mode.

5-10.3.2* Externally illuminated signs shall be illuminated by not less than 5 footcandles (54lx) and shall employ a contrast ratio of not less than 0.5.

5-10.3.3* The visibility of an internally illuminated sign shall be the equivalent of an externally illuminated sign that complies with 5-10.3.2.

Exception No. 1: Approved Existing Signs

Exception No. 2*: Approved self-luminous or electroluminescent signs that provide evenly illuminated letters shall have a minimum luminance of 0.06 footlamberts as measured by a color-corrected photometer.

5-10.3.4 Every sign required by 5-10.1.4 shall provide evenly illuminated letters having a minimum luminance of 0.06 footlamberts

Exception: Signs complying with the requirements of 5-10.3.3 are acceptable.