Section 63K(1)(b) in The West Bengal Factories Rules, 1958
(b)For factories employing 51 to 250 workers :-(i)there shall be an Occupational Health Centre having room with a minimum floor area of 15 sq.m. with floors and walls upto a height of 1.5 metres made a smooth and impervious surface. The Occupational Health Centre shall be provided with adequate illumination and ventilation as well as equipment as per the Schedule annexed to this rule;(ii)there shall be a Factory Medical Officer in overall charge of the centre who shall attend the center at least thrice in a week and whose services shall be readily available during emergencies;(iii)there shall be one qualified and trained dresser-cum-compounder on duty in each shift;(iv)adequate number of fully equipped first-aid boxes shall be provided in the factory.