Okla. Stat. tit. 45, § 45-516: Ventilation

The operator of every coal or other mine, whether shaft, slope

or drift shall provide and hereafter maintain ample means of

ventilation affording not less than one hundred fifty (150) cubic

feet of air per minute, for each and every person employed therein,

and seven hundred fifty (750) cubic feet of air per minute for every

animal employed therein; but, in a mine where fire damp has been

detected, the minimum shall be two hundred (200) cubic feet per

minute for each person employed therein, and as much more in either

case as one or more of the mine inspectors may deem requisite, and

the ventilation shall be conducted through the main cross entries

and all other working places, so as to dilute and render harmless

and expel therefrom the noxious and poisonous gases, and all working

places shall be kept clear of standing gases.