ISSUE DATE: 03/14/08 

PROGRAM INFORMATION BULLETIN NO. P08-06 

FROM: KEVIN G. STRICKLIN

 Administrator for 

 Coal Mine Safety and Health 

 FELIX A. QUINTANA

 Administrator for 

 Metal and Nonmetal Mine Safety and Health 

 MARK E. SKILES

 Director of Technical Support

SUBJECT: MSHA Approval of Electric Cap Lamps 

Scope

This program information bulletin (PIB) is intended for Mine Safety and Health 

Administration (MSHA) personnel, equipment manufacturers, repair facilities, 

underground coal mine operators, gassy underground metal and nonmetal mine 

operators, underground independent contractors, miners’ representatives, and other 

interested parties. 

Purpose

This PIB is issued to inform the mining industry how MSHA applies Title 30 Code of 

Federal Regulations (30 C.F.R.) § 19.1(b), “Electric Cap Lamps” to evaluate cap lamps 

with associated electronic circuitry. 

Information

In an effort to address advancements in technology and designs of electric cap lamps, 

MSHA intends to evaluate cap lamps for compliance using MSHA’s “Criteria for the 

Evaluation and Test of Intrinsically Safe Apparatus and Associated Apparatus” 
2

(http://www.msha.gov/techsupp/acc/application/acri2001.pdf), where applicable, in 

addition to the existing 30 C.F.R. § 19.1(b) requirements. 

Background

The regulations for the approval of Electric Cap Lamps are specified in 30 C.F.R. Part 

19. This regulation was originally promulgated in 1939 and has not been substantially 

updated since. At the time Part 19 was promulgated, the authors did not address more 

recent developments in the design of electric cap lamps. The requirements for 

protection against explosion hazard are found in 30 C.F.R. § 19.7. This section is 

prefaced with the following statement: 

“Unless properly designed, electric cap lamps may present two sources of 

probable explosion hazards: Ignition of an explosive atmosphere by the heated 

filament of the bulb in case the bulb glass is accidentally broken, and ignition by 

sparks or flashes from the battery....” 

Section 19.7 also lists several requirements that are intended to address these hazards. 

These requirements were developed to address the technology in use at the time. For 

many years, the only designs developed and submitted for MSHA approval consisted 

of lead acid batteries directly powering an electric filament in a cap lamp headpiece. 

Recent electric cap lamp designs include newer battery chemistries such as nickel metal 

hydride and lithium ion. These new battery assemblies typically include electronic 

control circuitry. Additionally, electric cap lamps are now routinely designed to deliver 

power to accessories such as radio frequency identification (RFID) tags, and personal 

messaging devices or an accessory receptacle (power take-off or ‘PTO’) to power remote 

control transmitters. These accessories introduce additional electronic circuitry into the 

electric cap lamp design. 

Also, alternate lighting technologies are being incorporated into cap lamp headpieces. 

MSHA has processed applications that included fluorescent lamps or light emitting 

diodes (LEDs). These types of light sources require additional electronic circuitry. 

Section 19.7(e) requires cap lamp battery current to be restricted to a value that will not 

produce sparks that could ignite an explosive mixture of methane and air. In order to 

ensure that an adequate degree of safety is provided on new cap lamp designs, the 

A&CC is applying the “Criteria for the Evaluation and Test of Intrinsically Safe 

Apparatus and Associated Apparatus” to the evaluation of MSHA approval requests 

for electric cap lamps. These criteria have been used during the evaluation of all recent 

applications that include, but are not limited to, accessories, alternate light sources, or 

alternate battery chemistries. 

Authority

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

C.F.R. § 19.1. 
3

Internet Availability

This PIB may be viewed on the World Wide Web by accessing the MSHA home page 

(www.msha.gov) and choosing "Compliance Info" and "Program Information 

Bulletins." 

Issuing Office and Contact Person

MSHA, Approval and Certification Center 

Chad Huntley, (304) 547-2076 

E-mail: huntley.chad@dol.gov

Coal Mine Safety and Health 

Salwa El-Bassioni, (202) 693-9525 

E-mail: el-bassioni.salwa@dol.gov 

Metal and Nonmetal Mine Safety and Health 

William W. Wilson, (202) 693-9643 

E-mail: wilson.william@dol.gov 

Distribution

MSHA Program Policy Manual Holders 

Manufacturers of Mining Equipment and Mine Equipment Rebuild Facilities 

Miners’ Representatives 

Underground Mine Operators 

Underground Independent Contractors 

Special Interest Groups