Section 390(2)(c) in The Calcutta Municipal Corporation Act, 1980
(c)institutional buildings, that is to say, any buildings or part thereof ordinarily providing sleeping accommodation for occupants and used for the purposes of medical or other treatment or care of persons suffering from physical or mental illness, disease or infirmity, care of infants, convalescents or aged persons and for penal or correctional detention in which the liberty of the inmates is restricted; such buildings shall include hospitals, clinics, dispensaries, sanatoria, custodial institutions and penal institutions like jails, prisons, mental hospitals and reformatories;