Skip to content
U.S. Department of Labor

Mine Safety and Health Administration
201 12th Street South, Suite 401
Arlington, VA 22202-5450

EFFECTIVE DATE:   May 29, 2013 EXPIRATION DATE: 3/31/2024
LAST VALIDATED: 03/31/2021


                    Administrator for
                    Coal Mine Safety and Health

SUBJECT:    Maintenance of Cutting Bits on Continuous Mining Machines and Longwall
                       Shearers under 30 C.F.R. 75.1725(a)

Underground coal mine operators, miners and miners’ representatives, Mine Safety and Health Administration (MSHA) enforcement personnel, and other interested parties should have this information.

This Program Policy Letter (PPL) clarifies that cutting coal or rock with continuous mining machines or longwall shearers with damaged or missing cutting bits is a violation of 30 C.F.R. § 75.1725(a). This policy is designed to prevent the ignition of methane caused by damaged, worn, or missing cutting bits, and thereby prevent the accidents and injuries that can result.

Section 75.1725(a) provides “Mobile and stationary machinery and equipment shall be maintained in safe operating condition and machinery or equipment in unsafe condition shall be removed from service immediately.”

Using cutting bits with a carbide tip on continuous mining machines, roof bolting drill steels and longwall shearers and replacing damaged or missing bits reduces sparks associated with the cutting bits striking sandstone or other types of rock during mining.

Failure to replace damaged or missing cutting bits and the lugs used to hold the cutting bits in place can result in sparks which are the most common source of methane ignitions.  Operating continuous mining machines or longwall shearers with damaged or missing cutting bits or lugs will be considered unsafe.

Cutting coal or rock with continuous mining machines or longwall shearers that have damaged, worn, or missing cuttings bits have ignited methane resulting in serious injuries and fatalities.  From January, 2002 through March, 2012, there have been approximately 379 reported incidents of ignitions of methane while mining coal or rock with continuous mining machines and longwall cutting shearers.

The Federal Mine Safety and Health Act of 1977, as amended, 30 U.S.C. § 801 et seq., and 30 C.F.R. § 75.1725(a).

Internet Availability
This program policy letter may be viewed on the Internet by accessing MSHA’s homepage at ( then choosing “MSHA's Major Laws, Regulations and Policies” and then “Compliance Information” and select “Program Policy Letters.”

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

Coal Mine Safety and Health, Safety Division
Stephen J. Gigliotti, (202) 693-9479

MSHA Program Policy Manual Holders
Miners’ Representatives
Underground Coal Mine Operators
Special Interest Groups