law: Factories Act, 1948 
  33. Pits, sumps, opening in floors, etc. 
  (1) In every factory every fixed vessel, sump, tank, pit or
  
  opening in the ground or in a floor which by reason of its depth, situation, construction
  
  or contents, is or may be a source of danger, shall be either securely covered
  
  or securely fenced.
  (2) The State Government may, by order in writing, exempt,
  
  subject to such conditions as may be prescribed, any factory or class or
  
  description of factories in respect of any vessel, sump, tank, pit or opening
  
  from compliance with the provisions of this section.