(a) In this chapter:
(1) "Commission" means the Railroad Commission of Texas.
(2) "Pool," "common pool," "field," or "common source of supply" means a common reservoir.
(3) "Pool" means an underground reservoir containing a connected accumulation of crude petroleum oil, or natural gas, or both.
(4) "Product" and "product of oil or gas" mean a commodity or thing made or manufactured from oil or gas and derivatives or by-products of oil or gas, including refined crude oil, crude tops, topped crude, processed crude petroleum, residue from crude petroleum, cracking stock, uncracked fuel oil, treated crude oil, fuel oil, residuum, gas oil, naphtha, distillate, gasoline, kerosene, benzine, wash oil, waste oil, lubricating oil, casinghead gas, casinghead gasoline, blended gasoline, and blends or mixtures of oil, or gas, or any derivatives or by-products of them.
(b) "Oil" means crude petroleum oil, crude petroleum, and crude oil, and "gas" means natural gas. These terms shall not be construed as referring to substances different from those referred to in this chapter and other laws as "oil and gas" and these terms mean the same whether used in this chapter or in other laws relating to the conservation of oil and gas.