Section 10(1)(d) in Bihar Entertainments Tax Act, 1948
(d)that the entertainment is provided by an institution not conducted for profit and established solely for the purpose of promoting the public health or the interests of agriculture or of a manufacturing industry and consists solely of an exhibition of articles which are of material interest in connection with question relating to public health or agriculture, or of the products of the industry for promoting the interests of which the institution exists or of the materials, machinery, appliances or foodstuffs used in the production of those products.