Tex. Tax Code § 152.087
The taxes imposed by this chapter do not apply to the purchase, rental, or use of a fire truck, emergency medical services vehicle as defined by Section 773.003, Health and Safety Code, or other motor vehicle used exclusively for fire-fighting purposes or for emergency medical services when purchased by:
Acts 1981, 67th Leg., p. 1594, ch. 389, Sec. 1, eff. Jan. 1, 1982.
Amended by Acts 1989, 71st Leg., ch. 606, Sec. 3, eff. Jan. 1, 1990;
Acts 1993, 73rd Leg., ch. 169, Sec. 2, eff. Aug. 30, 1993;
Acts 1997, 75th Leg., ch. 165, Sec. 30.259, eff. Sept. 1, 1997.
Acts 2013, 83rd Leg., R.S., Ch. 161 (S.B. 1093), Sec. 19.011, eff. September 1, 2013.