law: Indian Boilers Act, 1923 
  11. Revocation certificate or Provisional order 
  The Chief Inspector may at any time withdraw or revoke any
  
  certificate or provisional order on the report of an Inspector or otherwise- 
  (a) if there is reason to believe that the certificate or provisional
  
  order has been fraudulently obtained or has been granted erroneously or without
  
  sufficient examination; or
  (b) if the boiler in respect of which it has been granted has
  
  sustained injury or has ceased to be in good condition; or
  (c) where the State Government has made rules requiring that
  
  boilers shall be in charge of persons holding 34[certificates of
  
  proficiency or competency], if the boiler is in charge of a person not holding
  
  the certificate required by such rules; or
  (d) where no such rules have been made, if the boiler is in
  
  charge of a, person who is not, having regard to the condition of the boiler in
  
  tile opinion of the Chief Inspector competent to have charge thereof
  Provided  that where the Chief Inspector withdraws or
  
  revokes a certificate or provisional order on the ground specified in clause
  
  (d), he shall communicate to the owner of the boiler his reasons in writing for
  
  the withdrawal or revocation, and the order shall not take effect until the
  
  expiry of thirty days from the receipt of such communication.