Okla. Admin. Code § 165:10-12-5
The following words or terms, when used in this Chapter, shall have the following meaning unless the context clearly indicates otherwise:
"Hazardous gas concentration" means a concentration that presents or causes a risk of accident or fire.
"Natural gas" means a highly compressible, highly expansible mixture of hydrocarbons having a low specific gravity and occurring naturally in gaseous form. Besides hydrocarbon gases, natural gas may contain appreciable quantities of nitrogen, helium, carbon dioxide, hydrogen sulfide, and water vapor.
"Person" means any individual, business association or corporation, partnership, governmental or political subdivision, public corporation, body politic and corporate public authority, trust or any other legal entity.
"Responsible party" means any person or persons responsible for a facility which is found to be causing a seeping natural gas occurrence.
"Seeping natural gas" means natural gas which has migrated into, under or around a structure at hazardous concentrations.
Okla. Admin. Code § 165:10-12-5