Section 1(4)(i) in The Tamil Nadu Building and Construction Workers (Conditions of Employment and Miscellaneous Provisions) Act, 1984
(i)engaged in the work of building construction or work of engineering construction which is not of a hazardous work wherein fifty or more workers are working or were working on any day of the proceeding twelve months and in any part of which any such building operation which is not of a hazardous work is being carried on or is ordinarily so carried on;