law: Indian Boilers Act, 1923 
  7. Registration 
  (1) The owner of any boiler which is not registered under the
  
  provisions of this Act may apply to the Inspector to have the boiler
  
  registered. Every such application shall be accompanied by prescribed fee.
  (2) On receipt of an application under sub-section (1), the
  
  Inspector shall fix a date, within thirty days or such shorter period as may be
  
  prescribed from the (late 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.
  (3) On the said date the Inspector shall proceed to measure and
  
  examine the boiler and to determine in the prescribed manner the maximum
  
  pressure, if any, at which such boiler may be used, and shall report the result
  
  of the examination to the Chief Inspector in the prescribed form.
  (4) The Chief Inspector, on receipt of the report, may- 
  (a) register the boiler and assign a register
  
  number thereto either forthwith or after satisfying himself that any structural
  
  alteration., addition or renewal which he may deem necessary has been made in
  
  or to the boiler or any steam-pipe attached thereto, or
  (b) refuse to register the boiler:
  Provided  that where the Chief Inspector refuses to register
  
  a boiler, he shall forthwith communicate his refusal to the owner of the boiler
  
  together with the reasons therefore.
  (5) The Chief Inspector shall, on registering the boiler, order
  
  the issue to the owner of a certificate in the prescribed form authorizing the
  
  use of the boiler for a period not exceeding twelve months at a pressure not
  
  exceeding such maximum pressure as he thinks fit and as is in accordance with
  
  the regulations made under this Act:
   27  [Provided that a certificate issued under this sub-section
  
  in respect of an economiser 28[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.]
  (6) The Inspector shall forthwith convey to the owner of the
  
  boiler the orders of the Chief Inspector and shall in accordance therewith
  
  issue to the owner any certificate of which the issue has been ordered, and,
  
  where the boiler has been registered, the owner shall within the prescribed
  
  period cause the register number to be permanently marked thereon in the
  
  prescribed manner.