(7)Interlocking arrangements. - (a) In each oven or drier efficient inter-locking arrangements shall be provided and maintained to ensure that -(i)all ventilating fans and circulating fans whose failure would adversely effect the ventilation rate or flow pattern are in operations before any mechanical conveyor that may be provided for feeding the articles to be processed in the oven or drier is put into operation :(ii)failure of any of the ventilating or circulating fans will automatically stop any conveyor as referred to in clause (i) as may be provided, as well as stop the fuel supply by closing the shut off valve and shut off the ignition in the case of gas or oil fired oven and in the case of electrically heated ovens switch off the electrical supply to the heaters;(iii)the above said mechanical conveyor is not in operation before the above said shut-off valve can be energized; and(iv)the failure of the above said conveyor will automatically close and above said shut off value in the case of ovens and driers heated by gas, oil or steam and reactivate the ignition system, or cut off the electrical heaters in the case of electrically heated ovens or furnaces.
