EFFECTIVE DATE: 07/26/2012 EXPIRATION DATE: 03/31/2014

PROCEDURE INSTRUCTION LETTER NO. I12-V-19

FROM: KEVIN G. STRICKLIN 

 Administrator for

Coal Mine Safety and Health 

GEORGE TRIEBSCH

Acting Director of Technical Support

SUBJECT: District Field Change Requests for Adding Proximity Detection Systems

Scope

This Procedure Instruction Letter (PIL) is intended for Coal Mine Safety and Health 

personnel. 

Purpose

The purpose of this PIL is to guide Mine Safety and Health Administration (MSHA)

inspection personnel who receive mine operator requests to add proximity detection 

systems to MSHA-approved mining machines. 

Procedure Instructions

Proximity detection is a technology that uses electronic sensors to detect motion or the 

location of one object relative to another. Proximity detection systems can provide a 

warning and stop mobile machines before a pinning, crushing, or striking accident 

occurs that could result in injury or death to miners. 

Underground mining machines equipped with proximity detection systems must be 

approved by MSHA as permissible equipment under Title 30 Code of Federal 

Regulations (30 C.F.R.) Part 18 for electrical machines or Part 36 for diesel machines

before they can be used in gassy areas of underground coal mines. 
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There are several avenues in the approval and installation process of a proximity 

detection system:

1. MSHA offers an optional program allowing proximity detection 

manufacturers to obtain acceptance of their proximity detection system. This program

is referred to as the Proximity Detection Acceptance (PDA) program and results in the 

issuance of a PDA number to a proximity detection system that has met the applicable 

requirements of Part 18.

2. Machine manufacturers with MSHA approvals may submit an application to 

MSHA’s Approval and Certification Center (A&CC) to add a proximity detection 

system to their approval. The machine manufacturer can submit a new approval 

request, an extension of approval request, or a RAMP (Revised Approval Modification 

Program) request to the A&CC to add the proximity detection system to the machine.

3. The mine operator can submit a field modification request to the A&CC to add 

a proximity detection system to the machine(s) they own.

4. For electrical machines, the mine operator can also submit a district field 

change request to the Coal Mine Safety and Health District Office to add a proximity 

detection system accepted under MSHA’s PDA program to a MSHA-approved machine 

it owns. 

The Coal Mine Safety and Health Electrical Inspection Procedures Handbook addresses 

district field changes. It provides a list of changes that can be made without sending an 

application letter to the A&CC, without processing a written field change report and 

acceptance letter, and without a visual inspection at the time of installation. This 

handbook will be revised to include the addition of proximity detection systems to 

approved mining machines as an acceptable district field change.

When requesting a district field change, coal mine operators are required to notify the 

district office in writing that the changes will be made in accordance with 30 C.F.R. Part 

18. A copy of all notifications shall be maintained in the appropriate mine file. 

Inspection of such changes shall be made as soon as practicable, but not later than one 

month after receipt of the notification. A record of such inspection shall be maintained 

in the mine file.

When processing a district field change, CMSH enforcement personnel should evaluate 

the request to determine whether the field change is adequately described or whether 

additional assistance from the A&CC is necessary. If A&CC assistance is required, the 

district should contact Kenneth Porter at 304-547-2030, porter.kenneth@dol.gov or 

Kevin Dolinar at 304-547-2014, dolinar.kevin@dol.gov. 
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Background

The Mine Safety and Health Administration anticipates that it will receive requests 

from manufacturers and mine operators to add proximity detection systems to MSHA 

approved machines. 

Authority

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

C.F.R. § 75.500(c) Permissible Electric Equipment and § 18.81 Field Modification of 

Approved (Permissible) Equipment

Internet Availability

This PIL may be viewed by accessing the MSHA home page (http://www.msha.gov) 

and choosing "Compliance Info" and "Procedure Instruction Letters." 

Issuing Offices and Contact Persons

Office of Technical Support

David Chirdon, (304) 547-2026

E-mail: chirdon.david@dol.gov

Coal Mine Safety and Health, Safety Division

John Arrington, (202) 693-9549

E-mail: arrington.john@dol.gov

Distribution

MSHA Program Policy Manual Holders

Manufacturers of Mining Equipment and Mine Equipment Repair Facilities 

Miners’ Representatives

Underground Coal Mine Operators

Underground Independent Contractors

Special Interest Groups