law: Indian Boilers Act, 1923 
  8. Renewal of certificate 
  (1) A certificate authorizing 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 boiler is moved, the boiler not
  
  being a vertical boiler the heating surface of which is less than 29[18.58
  
  square meters], 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; or
  (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 (1) 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 to the Inspector for a renewal thereof for such period not
  
  exceeding twelve months as he may specify in the application:
   30  [Provided that where the certificate relates to an
  
  economiser 31[or an unfired boiler which forms an integral part of a
  
  processing plant in which steam is generated solely by the use of oil, asphalt
  
  or bitumen as a heating medium], 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 days notice of the date so fixed
  Bthat, where the certificate has ceased to be in force owing to
  
  the making of any structural alteration, addition or renewal, the Chief
  
  Inspector may dispense with the payment of any fee:
   32  [Provided further that in the case of an economiser
  
  or of an unfired boiler which forms an integral part of a processing plant in
  
  which steam is generated solely by the use of oil, asphalt or bitumen as a
  
  heating medium, the date fixed for its examination shall be within sixty days
  
  from the date of receipt of the application and the owner shall be given not
  
  less than thirty days’ notice of the date so fixed.]
  (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 authorizing 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:
   33  [Provided that renewed certificate issued under
  
  this sub-section in respect of an economiser 31[or of an unfired
  
  boiler which forms an integral part of a processing plant in which steam is
  
  generated solely by the use of oil, asphalt or bitumen as a heating medium] may
  
  authorize its use for a period not exceeding twenty-four months :]
  Provided  33[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.