The properties, use, and testing of drilling fluids and the conduct of related drilling procedures shall be such as are necessary to prevent the blowout of any well. Sufficient drilling fluid materials to insure well control shall be maintained in the field area readily accessible for use at all times.

(1) Drilling fluid control. Before pulling drill pipe, the drilling fluid shall be properly conditioned or displaced. The hole shall be kept reasonably full at all times. Proper techniques shall be utilized when necessary to maintain mud characteristics for well control and hole conditioning. The conditions herein shall not apply when drilling with air or aerated fluids.

(2) Drilling fluid testing. Mud testing and treatment consistent with good operating practice shall be performed daily or more frequently as conditions warrant. The following drilling fluid system monitoring or recording devices shall be installed and operated continuously during drilling operations, with mud, occurring below the shoe of the conductor casing:

(a) High-low level mud pit indicator including a visual and audio-warning device, if applicable.

(b) A hydrogen sulfide indicator and alarm shall be installed in areas suspected or known by the supervisor to contain hydrogen sulfide gas which may reach levels considered to be dangerous to the health and safety of personnel in the area.

(c) Degassers shall be required if applicable, and below 7,500 feet (2286 meters) or in areas of known high pressure desilters and desanders if required for solids control.