(1) An ancillary space in a rapid transit station shall be separated from the remainder of the floor area by a fire separation having a fire-resistance rating not less than 1 h.
                                
                                
                                (2) Except as provided in Sentence (3), a door opening from a service room onto a means of egress in a rapid transit station shall be located not less than 5 m from an escalator balustrade and from the top and bottom riser of a flight used as a means of egress from the rapid transit station.
                                
                                
                                (3) The requirements in Sentence (2) do not apply where,
                                
                                
                                (a) the service room is sprinklered, or
                                
                                
                                (b) there is a vestibule between the service room and the means of egress.
                                
                                
                                (4) Where a door from a service room opens onto a means of egress less than 5 m wide,
                                
                                
                                (a) the service room shall be sprinklered, or
                                
                                
                                (b) there shall be a vestibule between the service room and the means of egress.