Each power ventilation system must have:
(a) A control to stop the ventilation that is:
(1) Outside the space ventilated; and
(2) Grouped with the controls for every power ventilation system to which this section is applicable; and
(b) In addition to the control required by paragraph (a), a stop control that is:
(1) As far as practicable from the control required by paragraph (a) and grouped with the controls for every power ventilation system to which this section is applicable; or
(2) The circuit breakers for ventilation grouped on the main switchboard and marked, ``In Case of Fire Trip to Stop Ventilation.''
Note: The requirements of this section do not apply to closed ventilation systems for motors or generators, diffuser fans for refrigerated spaces, room circulating fans, or exhaust fans for private toilets of an electrical rating comparable to that of a room circulating fan.