8.(1) A certificate authorising the use of a boiler shall cease to be in force- (a) on the expiry of the period for which it was granted; or (b) when any accident occurs to the boiler; or (c) when the bolier is moved, the boiler not being a vertical boiler the heating surface of which is less than ¹[18.58 square miters], or a portable or vehicular boiler; or (d) when any structural alteration, addition or renewal is made in or to the boiler; or (e) if the Chief Inspector in any particular case so directs, when any structural alteration, addition or renewal is made in or to any steam-pipe attached to the boiler; (f) on the communication to the owner of the boiler of an order of the Chief Inspector or Inspector prohibiting its use on the ground that it or any steam-pipe attached thereto is in a dangerous condition. (2) Where an order is made under clause (f) of sub-section (1), the grounds on which the order is made shall be communicated to the owner with the order. (3) When a certificate ceases to be in force, the owner of the boiler may apply may apply to the Inspector a renewal thereof for such period not exceeding twelve months as he may specify in the application: Provided that where the certificate relates to an economiser, the application for its renewal may be for a period not exceeding twenty-four months. (4) An application under sub-section (3) shall be accompanied by the prescribed fee and, on receipt thereof, the Inspector shall fix a date, within thirty days or such shorter period as may be prescribed from the date of the receipt, for the examination of the boiler and shall give the owner thereof not less than ten day's notice of the date so fixed: Provided that, where the certificate has ceased to be in force owing to the making of any structural alteration, addition or renewal to the Chief Inspector may dispense with the payment of any fee. Provided further in the case of an economiser, the owner shall be given not less than thirty day's notice of the date fixed for its examination. (5) On the said date the Inspector shall examine the boiler in the prescribed manner, and if he is satisfied that the boiler and the steam-pipe or steam-pipes attached thereto are in good condition shall issue a renewed certificate authorising the use of the boiler for such period not exceeding twelve months and at a pressure not exceeding such maximum pressure as he thinks fit and as is in accordance with the regulations made under this Act: Provided that a renewed certificate issued under this sub-section in respect of an economiser may authorise its use for a period not exceeding twenty-four months: Provided further that if the Inspector-(a) proposes to issue any certificate - (i) having validity for a less period than the period entered in the application, or (ii) increasing or reducing the maximum pressure at which the boiler may be used, or (b) proposes to order any structural alteration, addition or renewal to be made in or to the boiler or any steam-pipe attached thereto, or (c) is of opinion that the boiler is not fit for use, the Inspector shall, within forty-eight hours of making the examination, inform the owner of the boiler in writing of his opinion and the reasons therefor, and shall forthwith report the case for orders to the Chief Inspector. (6) The Chief Inspector, on receipt of a report under sub-section (5), may, subject to the provisions of this Act and of the regulations made hereunder, order the renewal of the certificate in such terms and on such conditions, if any, as he thinks fit, or may refuse to renew it: Provided that where the Chief Inspector refuses to renew a certificate, he shall forthwith communicate his refusal to the owner of the boiler, together with the reasons therefor. (7) Nothing in this section shall be deemed to prevent an owner of a boiler from applying for a renewed certificate therefor at any time during the currency of a certificate.