8/20/2025
In the matter of PETITION FOR MODIFICATION
Century Mining, LLC
Longview Mine
Mine I.D. No. 46-09447
Docket Number Regulation Petitioned
Docket No. M-2025-030-C 30 C.F.R. § 75.500(d)
PROPOSED DECISION AND ORDER
On March 3, 2025, Century Mining, LLC filed the above listed petition for modification seeking a modification of the application of the above-referenced standard to its Longview Mine located at 620 Peel Tree Road, Volga, WV 26238, to permit the use of Powered Air Purifying Respirators (PAPRs) inby the last open crosscut that MSHA has not approved as permissible under 30 C.F.R. Part 18. Specifically, the Petitioner is requesting to utilize the Drager X-Plore 8700 EX PAPR, the PureFlo ESM +Pf60 PAPR, and the 3M Versaflo TR-300N PAPR. The Petitioner alleges that the alternative method outlined in the petition will, at all times, guarantee no less than the same measure of protection afforded by the standard.
Title 30 C.F.R. § 75.500(d) Permissible electric equipment states:
All other electric face equipment which is taken into or used inby the last crosscut of any coal mine, except a coal mine referred to in § 75.501, which has not been classified under any provision of law as a gassy mine prior to March 30, 1970, shall be permissible.
The Petitioner states that:
1. It currently uses the MSHA-approved 3M Airstream Headgear-Mounted (Airstream) PAPR System to protect miners working on its longwall and continuous miner sections. The Airstream provides a constant flow of filtered air to protect against potential exposure to respirable coal mine dust during normal mining conditions inby the last open crosscut. The Airstream is being discontinued by the manufacturer, no replacement components will be available, and there are no other MSHA-approved units.
2. The Drager X-Plore 8700 EX PAPR is certified by CSA Group (formerly the Canadian Standards Association) according to ANSI/UL 60079-0:2022 (General Requirements) and ANSI/UL 60079-13 (Intrinsic Safety) standards.
3. The PureFlo ESM +Pf60 PAPR is a NIOSH approved respirator system.
4. The Drager X-Plore 8700 EX PAPR, the PureFlo ESM +Pf60 PAPR, and the 3M Versaflo TR-300N PAPR units are not MSHA approved as permissible and are not pursuing MSHA approval.
5. The alternative method in the petition will at all times guarantee no less than the same measure of protection afforded to the miners by the mandatory standard.
MSHA personnel investigated the merits of the petition with respect to the technical sufficiency of the proposed equipment. After a careful review of the merits of the petition, the Administrator issues this Proposed Decision and Order.
FINDINGS OF FACT AND CONCLUSIONS OF LAW
The term “Intrinsic Safety” is a safety methodology used in hazardous environments, such as underground mines, where gases like methane could ignite and cause an explosion. “Intrinsic Safety” means designing electrical equipment so it will not cause a spark or get hot enough to start a fire or ignite an explosion, even if something goes wrong with the subject device. “One-fault Intrinsic Safety” means an electrical device will not spark or overheat even if one component of the device fails. “Two-fault Intrinsic Safety” means an electrical device will not spark or overheat even if two independent components of the device fail at the same time, thereby offering a greater level of protection and safety.
MSHA’s existing approval standards, under 30 C.F.R. Part 18, require two-fault intrinsic safety for electrical and electronic equipment. As such, MSHA evaluates this equipment to ensure that it provides two-fault Intrinsic Safety as part of its certification process for permissibility. The criteria MSHA uses to evaluate equipment for Intrinsic Safety are published in a document referred to as ACRI2001 (MSHA, 2017).
NIOSH researchers, in a paper titled “An Evaluation of the Relative Safety of U.S. Mining Explosion-Protected Equipment Approval Requirements versus those of International Standards” (NIOSH, 2017), have determined that equipment that meets two-fault Intrinsic Safety as defined in the ANSI/UL 60079-11:13 standard “ia” would provide at least an equivalent level of safety as that provided by equipment approved by the MSHA criteria found in ACRI2001.
MSHA Enforcement submitted information regarding the Drager X-Plore 8700 EX PAPR, the PureFlo ESM +Pf60 PAPR, and the 3M Versaflo TR-300N PAPRs to the Agency’s technical experts at its Approval and Certification Center (A&CC). A&CC conducted a review and determined the following.
The Drager X-Plore 8700 EX model has received certification from CSA Group, which is a Nationally Recognized Test Laboratory, under ANSI/UL 60079-0:2020 and ANSI/UL 60079-11:13.
The CSA Group certification issued to Drager allows the Drager X-Plore 8700 EX to be marked as “Ex ib IIB T4 Gb” and “Ex ib IIIB T135°C Db”. These markings indicate the following:
1. The unit is certified to be used in hazardous locations, “Ex”
2. The unit has met the second-most onerous level of Intrinsic Safety protection, “ib”
3. The level of protection is acceptable for use in non-mining locations (“IIB” for gases and “IIIB” for dusts), and
4. The unit is not certified for use in mining applications.
In other words, the Drager X-Plore 8700 EX is certified as “ib” which means it only provides one-fault Intrinsic Safety. It is not certified as “ia” which means it does not provide two-fault Intrinsic Safety. Because one-fault Intrinsic Safety provides less protection from ignition and explosion hazards than MSHA’s standards that require two-fault Intrinsic Safety for electrical and electronic equipment, MSHA cannot approve the use of this PAPR.
The PureFlo ESM +Pf60 model has received certification from FM Approval, which is a Nationally Recognized Test Laboratory, for Class I, II, and III, Division 2, Groups A, B, C, D, E, F, and G. The National Electrical Code defines Class I Division 2 as locations with flammable gases, vapors, or liquids that exist only under abnormal conditions. Class II Division 2 locations are those with combustible dust that exist only under abnormal conditions. Class III Division 2 are locations with ignitable fibers and flyings that exist only under abnormal conditions. The PureFlo ESM +Pf60 model has not received any intrinsic safety certification. Because the device is not certified for use in mining conditions and because the device has no Intrinsic Safety, which provides less protection from ignition and explosion hazards that MSHA’s standards that require two-fault Intrinsic Safety for electrical and electronic equipment, MSHA cannot approve the use of this PAPR.
The 3M Versaflo TR-300N has not received any intrinsic safety certification. The technical data sheet provided by the petitioner for the 3M Versaflo TR-300N states that the “TR-300N assemblies and chargers are not intrinsically safe”. Because the device has no Intrinsic Safety, which provides less protection from ignition and explosion hazards that MSHA’s standards that require two-fault Intrinsic Safety for electrical and electronic equipment, MSHA cannot approve the use of this PAPR.
MSHA has determined that the requested PAPR models cannot be used as safely in areas where permissibility is required. The level of protection for which these PAPRs are certified does not provide the same level of protection as MSHA’s requirement or the standards noted by NIOSH. MSHA’s requirements include the use of two faults of Intrinsic Safety be applied to the circuitry, which the Drager X-Plore 8700 EX, PureFlo ESM +Pf60, and 3M Versaflo TR-300N do not meet.
MSHA notes that Petitioner does still have a viable, alternative PAPR option, namely the use of the CleanSpace EX PAPR, which was a modification previously granted to the subject operator and mine.
ORDER
Wherefore, pursuant to the authority delegated by the Secretary of Labor to the Administrator for Mine Safety and Health Enforcement and pursuant to Section 101(c) of the Federal Mine Safety and Health Act of 1977, 30 U.S.C. § 811(c), it is ordered that Century Mining LLC’s Petition for Modification of the application of 30 C.F.R. § 75.500(d) in the Longview Mine is hereby:
DENIED
Any party to this action desiring a hearing on this matter must file in accordance with 30 C.F.R. § 44.14 within 30 days. The request for hearing must be filed with the Administrator for Mine Safety and Health Enforcement, 200 Constitution Avenue NW, Washington, DC 20210.
If a hearing is requested, the request shall contain a concise summary of position on the issues of fact or law desired to be raised by the party requesting the hearing, including specific objections to the proposed decision. A party other than the Petitioner who has requested a hearing may also comment upon all issues of fact or law presented in the petition and any party to this action requesting a hearing may indicate a desired hearing site. If no request for a hearing is filed within 30 days after service thereof, the Decision and Order will become final and must be posted by the operator on the bulletin board at the mine.
Timothy R. Watkins
Acting Administrator for
Mine Safety and Health Enforcement
Certificate of Service
I hereby certify that a copy of this proposed decision was served personally or
mailed, postage paid, or provided by other electronic means this 20th day of
August, 2025, to:
Daniel E. Curry
Safety Manager
Century Mining
7004 Buckhannon Road
Volga, WV
dcurry@alleghenymet.com
Alexander Bullinger
General Engineer