Section 31(2)(i) in The Iron Ore Mines, Manganese Ore Mines And Chrome Ore Mines Labour Welfare Fund Rules, 1978
(i)the common main maternity centre shall maintain the prescribed standard for the aggregate number of workers of all Iron Ore or Manganese Ore Mines [and Chrome Ore Mines] [Inserted by G.S.R. 535(E), dated 28.6.1983 (w.e.f. 1.7.1983). ] served by it or the standard maintained by it during the year 1975, whichever is higher;