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U.S. Department of Labor


Mine Safety and Health Administration
1100 Wilson Boulevard
Arlington, Virginia 22209-3939
EFFECTIVE DATE:   May 11, 2012 EXPIRATION DATE: 03/31/2014
(Reissue of P08-V-7)              

PROGRAM POLICY LETTER NO. P12-V-06

FROM:          GEORGE H. GARDNER GEORGE H. GARDNER
                    Acting Director of Technical Support

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

SUBJECT:     Longwall Lighting Cables

Scope
This Program Policy Letter (PPL) applies to underground coal mine operators, manufacturers of longwall systems, facilities that rebuild longwall systems, and Mine Safety and Health Administration (MSHA) enforcement and technical support personnel.

Purpose
The purpose of this PPL is to clarify that longwall lighting system cables should be treated as trailing cables for splicing purposes under Title 30 Code of Federal Regulations (30 C.F.R.) Parts 18 and 75.

Policy
Cables between a starter/controller of an MSHA-approved longwall system and power supply enclosure(s) for light fixtures installed on roof support equipment of the longwall are considered to be trailing cables, although these cables also have characteristics of intra-machine cables. For splicing and other purposes, these longwall lighting cables should be treated in a similar fashion as longwall motor and shearer cables as specified in Volume II § 18.20 of MSHA's Policy and Procedures Manual (PPM).

Background
Title 30 C.F.R. § 75.1719-2(e) states in part that "[c]ables conducting power to stationary lighting fixtures from both alternating and direct power current sources, other than intrinsically safe devices, shall be considered trailing cables, and shall meet the requirements of Subpart G of this part." MSHA's PPM under § 75.1719-2 clarifies that "[l]ight fixtures installed on roof support equipment of longwall or shortwall mining systems shall be considered stationary light fixtures." Under these authorities, lighting fixtures installed on roof support equipment of longwall or shortwall mining systems are stationary lighting fixtures and the cables supplying power to these fixtures are trailing cables subject to 30 C.F.R. pt. 75, subpart G, which allows for splicing in certain circumstances.

However, longwall lighting cables also are located directly on the longwall equipment. MSHA policy at PPM Vol. V § 75.503 states that "[s]plices shall not be made in external wiring of permissible [electric face] equipment except in connection boxes as originally approved." Under the same policy, splices may not be made in cables of intrinsically safe circuits unless the splices are in splice boxes or the cables are joined by proper connecting plugs. Longwall lighting cables arguably could be considered "external wiring of permissible [electric face] equipment" subject to the § 75.503 splicing policy. For this reason, inconsistencies have arisen among the districts as to whether longwall lighting cables are trailing cables or intra-machine cables. Districts have allowed or prohibited splicing depending upon whether they considered these cables to be trailing cables or intra-machine cables. MSHA is clarifying that longwall lighting cables are trailing cables for splicing purposes and that the PPM guidelines for motor and shearer cables as specified in Volume II § 18.20 also should be applied to longwall lighting cables.

Longwall motor and shearer cables, like trailing cables, are not contained within the common frame of a machine and can be exposed to damage from contact with surfaces of the mine terrain and mining equipment. Also, these cables vary in length that can exceed 1000 feet. The length of cable between a starter/controller of an MSHA-approved longwall system and the power supply enclosure(s) for light fixtures installed on the longwall roof support equipment fits into the same category for splicing purposes as longwall motor and shearer cables. These lighting system cables are constructed with flame-resistant heavy duty jackets having outer dimensions meeting the requirements of 30 C.F.R. § 18.35(a)(6) and can vary from 100 feet to more than 1000 feet. Also, like trailing cables, they can be exposed to damage from contact with surfaces of the mine terrain and mining equipment.

Authority
The Federal Mine Safety and Health Act of 1977, as amended, 30 U.S.C. § 801 et seq.; 30 C.F.R. §§ 18.20(b), 75.503, 75.603, 75.604, and 75.1719-2.

Internet Availability
This PPL may be viewed on the Internet by accessing MSHA home page (http://www.msha.gov) and then choosing Compliance Assistance Information.

Issuing Office and Contact Persons
Coal Mine Safety and Health, Safety Division
John Arrington, (202) 693-9549
E-mail: arrington.john@dol.gov

Technical Support, Approval and Certification Center
Kenneth J. Porter, (304) 547-2030
E-mail: porter.kenneth@dol.go

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Distribution
MSHA Program Policy Manual Holders
MSHA Special Interest Groups
Underground Mine Operators
Repair Shops
Manufacturers of Longwall Systems