Ariz. Admin. Code § 11-1-1843
Current through Register Vol. 30, No. 50, December 13, 2024
The main ventilation shall be so arranged by means of air locks, overcasts, or undercasts that the passage of trips or persons does not cause interruptions of air currents. Where air locks are impracticable, single doors may be used if they are attended constantly while the areas of the mine affected by the doors are being worked, unless they are operated mechanically or are self-closing.
Ariz. Admin. Code § R11-1-1843