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U.S. Department of Labor

Mine Safety and Health Administration
201 12th Street South, Suite 401
Arlington, VA 22202-5450
ISSUE DATE: August 16, 2010
LAST VALIDATED: 03/31/2021


FROM:             KEVIN G. STRICKLIN  
                       Administrator for
                       Coal Mine Safety and Health

SUBJECT:     30 C.F.R. § 75.324, Intentional Changes In The Ventilation System

This Program Information Bulletin (PIB) applies operators of underground coal mines, miners' representatives, Mine Safety and Health Administration (MSHA) enforcement personnel, and other interested parties.

This Program Information Bulletin (PIB) emphasizes an operator's obligation under 30 C.F.R. § 75.324 to take specified steps to assure the health and safety of miners whenever making an intentional change to a ventilation system.

The mandatory coal mine safety standard concerning intentional changes in the ventilation system, 30 C.F.R. § 75.324, provides that a person designated by the operator shall supervise any intentional change in ventilation that:

The following is a list of some examples of what MSHA considers intentional changes that would materially affect the safety or health of miners. These examples are not meant to include all possibilities, but are meant to provide some general guidance:

Under 30 C.F.R. § 75.370(d), "Any intentional change to the ventilation system that alters the main air current or any split of the main air current in a manner that could materially affect the safety and health of the miners, or any change to the information required in § 75.371 shall be submitted to and approved by the district manager before implementation."

Under 30 C.F.R. § 75.324(b), intentional changes in the ventilation system may be made only under the following conditions:

Failure to follow 30 C.F.R. § 75.324 can create serious health and safety hazards. As a result, MSHA has determined that one operator's failure to comply with the provisions of § 75.324 constituted a "flagrant" violation of the Federal Mine Safety and Health Act of 1977, and the Agency will continue to use appropriate enforcement tools to assure compliance with these and other mandatory safety and health standards.

MSHA maintains an anonymous hotline to report hazardous conditions. The phone number is 1-800-746-1553. Persons may also report hazardous conditions to their MSHA District office. MSHA will promptly investigate any report of a hazardous condition at a mine.

On April 21, 2010, MSHA launched inspections at 57 coal mines whose enforcement history indicated a significant number of violations related to methane accumulations, ventilation, rock dusting applications, and mine examinations. These impact inspections followed the April 5, 2010, explosion at the Upper Big Branch Mine in Montcoal, West Virginia, and focused attention on mine ventilation, rock dusting, methane monitoring, and mine examinations.

In addition, on May 24, 2010, the House Education and Labor Committee conducted a hearing on the Upper Big Branch explosion. The Committee heard testimony from deceased miners' families. The testimony addressed issues regarding safety conditions in existence prior to the explosion including inadequate ventilation, intentional changes to ventilation systems, high levels of methane, excessive coal float dust, "bridging out" methane monitors on mining equipment, advance notice of MSHA inspections, and retaliation for miners who raised safety and health issues.

This PIB emphasizes that MSHA intends for mine operators to fully comply with the Mine Act and MSHA's regulatory requirements.

The Federal Mine Safety and Health Act of 1977, as amended, 30 U.S.C. § 801 et seq.; 30 C.F.R. §§ 75.324, 75.370, and 75.371.

Internet Availability
This PIB may be viewed on the Internet by accessing MSHA's home page at (, choosing "Compliance Info" and "Program Information Bulletins."

Issuing Office and Contact Person
Mine Safety and Health Enforcement
Don Vickers, (202) 693-9760

MSHA PPM holders
Underground Coal Mine Operators
Coal Miners' Representatives
Independent Contractors
Special Interest Groups