There shall be exempted and excluded from the measure of the taxes imposed by this chapter, all fixtures that are categorized as machinery and other mechanical or other allied equipment which are primarily and substantially used in manufacturing or producing tangible personal products.
(Sec. 8-10.16, R.O. 1978 (1983 Ed.)) (1990 Code, Ch. 8, Art. 10, § 8-10.16)