(1)
An emergency power supply capable of operating under a full load for not less than 2 h shall be provided by an emergency generator for
(a)
every elevator serving storeys above the first storey in a building that is more than 36 m high measured between grade and the floor level of the top storey and every elevator for firefighters in conformance with Sentence (2),
(b)
except as provided in Sentence (4), equipment that supplies water for fire suppression as required by Articles 3.2.5.7. and 3.2.5.8. and Sentences 3.2.5.12.(1) and (2) and 3.2.5.18.(1), if the supply depends solely on electrical power supplied to the building,
(c)
fans and other electrical equipment that are installed to maintain the air quality specified in Articles 3.2.6.2. and 3.3.3.6.,
(d)
fans required for venting by Article 3.2.6.6., and
(e)
fans required by Clause 3.2.8.4.(1)(c) and Article 3.2.8.7. in buildings within the scope of Subsection 3.2.6. (See Note A-3.2.7.9.(1))
(2)
Except as permitted by Sentence (3), the emergency power supply for elevators required by Clause (1)(a) shall be capable of operating all elevators for firefighters plus one additional elevator simultaneously.
(3)
Sentence (2) does not apply if the time to recall all elevators under emergency power supply is not more than 5 min, each from its most remote storey to
(a)
the storey containing the entrance for firefighter access referred to in Articles 3.2.5.4. and 3.2.5.5., or
(b)
to a transfer lobby.
(4)
The emergency power supply required by Clause (1)(b) for the equipment that supplies water for fire suppression need not be provided for sprinkler systems conforming to NFPA 13D, “Standard for the Installation of Sprinkler Systems in One- and Two-Family Dwellings and Manufactured Homes.”