293.120. Air safety requirements.
Air safety requirements.
293.120. Air in which men work or travel in mines shall beimproved when:
(1) It contains less than nineteen and five-tenths percentoxygen;
(2) It contains more than one-hundredth percent carbonmonoxide;
(3) It contains more than five-tenths percent carbondioxide;
(4) It contains more than one percent methane; or
(5) Is contaminated with dust or with noxious or poisonousgases in excess of accepted limits as established by the directorof the division of mine inspection.
(L. 1959 S.B. 188 § 13)