EFFECTIVE DATE: 3/7/2011 EXPIRATION DATE: 3/31/2013

(Reissue of P09-V-05)

PROGRAM POLICY LETTER NO. P11-V-02 

FROM: KEVIN G. STRICKLIN

 Administrator for 

 Coal Mine Safety and Health 

SUBJECT: Application of Title 30, Code of Federal Regulations (C.F.R.) 

 § 75.523-2 to Mobile Bridge Carriers Connected to Continuous

 Miners That Form Component Part of Self-Propelled Electric 

 Face Equipment

Scope

This Program Policy Letter (PPL) is intended for Coal Mine Safety and Health 

enforcement personnel, equipment manufacturers, underground coal mine operators, 

and independent contractors working at underground coal mines. 

Purpose

This PPL is issued to clarify 30 C.F.R. § 75.523-2, De-energization of self-propelled 

electric face equipment; performance requirements. The de-energization performance 

requirements of this section apply to all mobile bridge carriers (MBCs) that are 

mechanically or electrically connected to continuous miners (CMs) when they are 

component parts of a continuous mining and haulage system. 

Background

In 1999, as a result of an accident involving an MBC and a CM, the Mine Safety and 

Health Administration (MSHA) issued a citation pursuant to 30 C.F.R. § 75.523-2(c). 

Subsequently, a Federal Mine Safety and Health Review Commission administrative 

law judge (ALJ) issued a decision in the case of Secretary of Labor v. Rosebud Mining 

Company, 22 E.M.S.H.R.C.525(2000). The ALJ found that MSHA's enforcement policy 

regarding 30 C.F.R. § 75.523-2 was unclear. He reasoned that because the standard does 

not explicitly require that the panic bar on the MBC be able to de-energize the 

continuous miner, or define both pieces of equipment as different components of a 

single system of "self-propelled electric face equipment," and because MSHA's previous 

policy did not clarify the issue, "a reasonable operator familiar with the [mining] 

industry and the protective purposes of the standard" would not recognize that 30 

C.F.R. § 75.523-2 was applicable in the manner interpreted by MSHA Id. at 534.
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Furthermore, the ALJ noted that MSHA's most recent statement on de-energization 

devices appeared to "take a position counter to that advocated in this case" because it 

seemed to state that a continuous miner was not included in an "entire system." Id. at 

533. This policy letter clarifies the Agency's application of 30 C.F.R. § 75.523-2 to MBCs 

that are mechanically or electrically connected to CMs; MSHA considers the MBCs and 

the CMs to be part of a single system of electric face equipment. 

Policy

When MBCs and CMs are mechanically or electrically connected to each other, they are 

components forming a continuous haulage system of self-propelled electric face 

equipment. Even though the components may be trammed independently, an 

emergency stop switch must be installed on each machine and wired to simultaneously 

de-energize the tramming motors of all components (MBC and CM) when any 

emergency stop switch in either machine is activated. A hazardous condition can occur 

when the machines are mechanically or electrically connected to each other, but 

trammed independently, and the emergency stop switch of any machine fails to deenergize the tramming motors of all components in the event of an emergency. 

MBCs and CMs that do not have an emergency stop switch on all components that meet 

all the requirements of 30 C.F.R. § 75.523-2 are not in compliance with 30 C.F.R. § 

75.523-2. 

Section 75.523-2(a) provides that de-energization of the tramming motors of selfpropelled electric face equipment shall be provided by: 

(1) Mechanical actuation of an existing pushbutton emergency stopswitch; 

(2) Mechanical actuation of an existing lever emergency stopswitch; or 

(3) The addition of a separate electromechanical switch assembly.

Section 75.523-2(b) states that "[t]he existing emergency stopswitch or additional switch 

assembly shall be actuated by a bar or lever which shall extend a sufficient distance in 

each direction to permit quick deenergization of the tramming motors of self-propelled 

electric face equipment from all locations from which the equipment can be operated." 

Section 75.523-2(c) states that "[m]ovement of not more than 2 inches of the actuating 

bar or lever resulting from the application of not more than 15 pounds of force upon 

contact with any portion of the equipment operator's body at any point along the length 

of the actuating bar or lever shall cause de-energization of the tramming motors of the 

self-propelled electric face equipment." 

A violation of 30 C.F.R. § 75.523-2 exists and a citation shall be issued whenever an 

emergency panic bar installed on an MBC connected to a CM does not meet the 
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performance requirements of 30 C.F.R. § 75.523-2 (a), (b), and (c). 

The interpretation set forth above is consistent with the language of 30 C.F.R. §§ 75.523-

2 (a), (b), and (c) in that the MBCs and CMs that are connected form two or more 

components of one unit of self-propelled electric face equipment. Emergency deenergization of the tramming motors of all components is necessary to further the safety 

objectives of 30 C.F.R. §§ 75.523-2 (a), (b), and (c). The purpose of this standard is to 

prevent miners from being endangered by the unexpected movement and/or 

electrification of any component of the system of self-propelled electric face equipment. 

The standard is intended to provide that electric face equipment be de-energized 

quickly in the event of an emergency, thereby preventing equipment operators from 

being pinned, squeezed, or crushed against the roof, ribs or other mining equipment 

which could possibly result in a serious or fatal injury. 

In setting an abatement time for any violation described above, an inspector or other 

authorized agency representative should, at a minimum, consider the hazard(s) to 

miners and the reasonable time required to correct the condition. 

Authority

Federal Mine Safety and Health Act of 1977, as amended, 30 U.S.C. § 801 et seq,; 30 

C.F.R. § 75.523-2. 

Filing Instructions

This policy letter should be filed behind the tab marked "Program Policy Letters" at the 

back of Volume V of the Program Policy Manual. 

Internet Availability

This program policy letter may be viewed on the World Wide Web by accessing the 

MSHA home page (http://www.msha.gov) and choosing "Compliance Info" and 

"Program Policy Letters." 

Issuing Office and Contact Person

Coal Mine Safety and Health, Safety Division

John Arrington, (202) 693-9549

E-mail: arrington.john@dol.gov

Distribution

Program Policy Holders

Equipment Manufacturers

Underground Coal Mine Operators

Underground Independent Contractors

Special Interest Groups