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Petition Docket No. M-2022-028-C


In the matter of    Petition for Modification
Crimson Oak Grove Resources, LLC Oak Grove Mine
I.D. No. 01-00851    Docket No. M-2022-028-C


On October 13, 2022, Crimson Oak Grove Resources, LLC filed a petition seeking modification of the application of 30 C.F.R. § 75.500(d) to its Oak Grove Mine located near Adger, Alabama. A subsequent letter dated October 25, 2022 acknowledged receipt of the referenced petition for modification. The petitioner alleges that 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 standard.

The petitioned standard, 30 Code of Federal Regulations (30 C.F.R.) § 75.500(d) states,

(d) 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.

Petitioner is requesting a modification of the standard to allow the use of unapproved Power Air Purifying Respirators (PAPRs) in or inby the last open crosscut. Specifically, the petitioner is requesting to utilize the CleanSpace EX Powered Respirator.
The petitioner states that:
1.    Oak Grove Mine previously used the 3M Airstream helmet to provide miners respirable dust protection on the longwall faces. 3M has discontinued the Airstream helmet and there are no other MSHA approved PAPRs available.
2.    The CleanSpace EX Power Unit, manufactured by CleanSpace, has been determined to be intrinsically safe under IECEx and other countries’ standards which provides the same level of protection. CleanSpace is not pursuing MSHA approval.
3.    The equipment shall be examined at least weekly by a qualified person according to 30 C.F.R. § 75.512-2 and the examination results will be recorded weekly and may be expunged after one year.
4.    The petitioner will comply with 30 CFR 75.323.
5.    A qualified person as defined in 30 C.F.R. § 75.151 will monitor for methane as is required by the standard in the affected area of the mine.
6.    When not in operation, the batteries for the PAPR will be charged on the surface or underground in or inby the last open crosscut.
7.    The following battery charging products will be used: PAF-0066, PAF-1100.
8.    Qualified miners will receive training regarding how to safely use, care for, inspect the PAPR, and the Decision and Order before using the equipment in the relevant part of the mine. A record of the training will be kept and made available upon request.
MSHA personnel conducted an investigation relevant to the merits of the petition and filed a report of their findings with the Administrator for Mine Safety and Health Enforcement. After a careful review of the entire record, including the petition and MSHA's investigative report, the Administrator issues this Proposed Decision and Order.

Findings of Fact and Conclusions of Law

MSHA investigators conducted an investigation of the Oak Grove Mine on February 14, 2023. The MSHA investigator was accompanied by one Crimson Oak Grove Resources, LLC representative and one representative of the United Mine Workers of America (UMWA).

The Oak Grove Mine is located at 8800 Oak Grove Mine Road, Adger, Jefferson County, Alabama. The Oak Grove Mine is a vertical shaft and slope underground mine extracting coal from the Blue Creek coal seam by means of a longwall mining system and continuous miners. The Oak Grove Mine reported 12-month coal production of 1,835,149 tons for CY 2022. The mine liberates approximately 4,998,215 cubic feet of methane in a 24-hour period.

The Oak Grove Mine employees are represented by the UMWA, and all underground miners are affected by the petition.

Intrinsic Safety

Information regarding the UL listing for the CleanSpace EX PAPR was previously submitted to the MSHA Approval and Certification Center (A&CC). At that time a
review was requested for the use of this unapproved PAPR in areas of mines where permissibility is required. A&CC conducted the reviews and concluded that:

1.    The CleanSpace EX is certified by TestSafe Australia (TSA) according to the IEC 60079-0:2011 (General Requirements) and IEC 60079-11:2011 (Intrinsic Safety) standards. The certificate, issued to PAFtec Australia Pty Ltd ("PAFtec"), allows PAFtec to mark the device as "Ex ib IIB T4 Gb" and "Ex ia I Ma." Due to legal and regulatory constraints, the TSA certificate is not accepted by MSHA as evidence that the PAPR is approved for use in US mines. The IEC certification marking that applies to mining, Ex ia I Ma, is discussed below:

2.    The CleanSpace EX is certified to be used in hazardous locations (“Ex”); meets the most onerous level of intrinsic safety protection (“ia”); the level of protection is acceptable for use in mining locations (“I”), and the Equipment Protection Level appropriate for mining equipment, that has a "very high" level of protection, with sufficient security that it is unlikely to become an ignition source in normal operation, during expected malfunctions or during rare malfunctions, even when left energized in the presence of an outbreak of gas (“Ma”).

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”, have determined that equipment which meets two-fault intrinsic safety as defined in the ANSI/UL 60079 standard would provide at least an equivalent level of safety as that provided by equipment approved to MSHA criteria.

The UL certification, TSA certification and PAFtec listing material (drawings, certificate and text report) were found to support the conclusion that the CleanSpace EX meet the applicable “two fault” intrinsic safety requirements for mining equipment as found in the ANSI/UL standard.

The CleanSpace EX carries an ingress protection rating of IP66. This rating exceeds the minimum rating of IP54 required by the ANSI/UL and IEC standards for intrinsically safe mining equipment.

Electromagnetic Interference Investigation

Investigators performed tests to determine if there were any electromagnetic interferences between the CleanSpace EX Powered Respirator and any other electrical equipment or other electrical components worn by the miners at this mine. MSHA investigators traveled underground to the 3 South longwall section and 5 North continuous mining section of the Oak Grove Mine.
The CleanSpace EX electrical components such as the pump motor or battery can create a potential for electromagnetic interference when in close proximity to other electrical equipment. Mining conditions on the sections were as follows: six to nine feet mining height, wet, with metal roof and rib bolts. Mine personnel provided electrical equipment typically used in conjunction with the PAPR for testing.


The CleanSpace EX PAPR design features a facemask connected by hoses to a pack that contains the pump motor, filter, and battery, which rests on the back of the neck. The investigator first performed baseline functionality tests for all electrical equipment involved in the testing, including the PAPR, by operating them individually away from one another. Then concluded testing by positioning the running PAPR in various orientations and distances from miner-worn or carried battery powered electrical equipment as well as other electrical equipment as identified below in Table 1. The potential for electromagnetic interference rises as electrical equipment and PAPR operate close together, so distances tested ranged from twelve inches to zero inches.

Table 1: Electrical Equipment Tested for Electromagnetic Interference

Equipment Type




Multi-Gas Detector


Model # M-sam2500

S/N DRLM 0377



Thermo Scientific

Model # 3700-A1 S/N 80431


Cap Lamp

Wisdom Wise Lite 2

Model # USAID 0372

S/N 12887970


Big Face Methane Spotter


Model # 102LD S/N 16612




Model # Nx203

S/N CIC10046


Shearer Remote

Joy Mining Machinery

Model # 101130600 S/N 415710BE016


Tracking Puck


Model # MDGt1000 APP# 19-a040001-0


Cap Lamp

Wheat Kholer

Corded permissible

Model # L1 S/N 80431


CM Remote

Joy Mining Machinery

Model # MTX3 S/N 172202BB014A


Proximity Detector

Joy Proximity

Model # ECM1432297


Multi-Gas Detector

Industrial Scientific

Model # Ventis MX4 S/N 2105298-004


Text Pager


Model # 2 WC-T S/N 01309209257


Conclusion: The investigator did not observe any apparent electromagnetic interference or performance issues between the proposed PAPR and the electrical equipment typically worn, carried or used on the Longwall and Continuous Miner Sections. MSHA determined that the CleanSpace EX PAPR can be safely used where permissible equipment is required in or inby the last open crosscut if the operator follows all manufacturer’s recommendations and adheres to the Terms and Conditions of the Proposed Decision and Order.

On the basis of the petition and the findings of MSHA’s investigation, Crimson Oak Grove Resources, LLC is granted a modification of the application of 30 C.F.R. § 75.500(d) to its Oak Grove Mine.

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 Crimson Oak Grove Resources, LLC ’s Petition for Modification of the application of 30
C.F.R. § 75.500(d) in the Oak Grove Mine is hereby:
GRANTED, for the operator who may use the CleanSpace EX PAPR in or inby the last open crosscut, subject to the conditions of this Order:

1.    Affected mine employees must be trained in the proper use and maintenance of the CleanSpace EX PAPR in accordance with established manufacturer guidelines. This training shall alert the affected employee that the CleanSpace EX PAPR is not approved under 30 CFR Part 18 and therefore must be de-energized when 1.0 or more percent methane is detected. The training shall also include the proper method to de-energize this PAPR. In addition to manufacturer guidelines, MSHA will require that mine employees be trained to inspect the units before use to identify any damage to the units that would negatively impact intrinsic safety as well as all stipulations in this petition.

2.    The CleanSpace EX PAPR, including the power unit assembly and all associated wiring and connections must be inspected before use to identify any damage to the units that would negatively impact intrinsic safety. If any defects are found, the PAPR must be removed from service.

3.    The operator will maintain a separate logbook for the CleanSpace EX PAPRs that shall be kept with the equipment, or in a location with other mine record books and shall be made available to MSHA upon request. The equipment shall be examined at least weekly by a qualified person as defined in 30 CFR § 75.512-1 and the examination results recorded in the logbook. Since float coal dust is removed by the air filter prior to reaching the motor, the PAPR user shall conduct regular
examinations of the filter and perform periodic testing for proper operation of the “blocked filter” alarm on the CleanSpace EX PAPR. Examination entries may be expunged after one year.

4.    All CleanSpace EX PAPRs to be used in or inby the last open crosscut, shall be physically examined prior to initial use and each unit will be assigned a unique identification number. Each unit shall be examined by the person to operate the equipment prior to taking the equipment underground to ensure the equipment is used according to the original equipment manufacturer’s recommendations and maintained in a safe operating condition. The CleanSpace EX PAPR does not have an accessible/removable battery. The internal battery and motor/blower assembly are both contained within the “power unit” assembly and the battery cannot be removed, reinserted or fastened. Therefore, examination of the CleanSpace EX PAPR should include any indications of physical damage.

5.    The operator is to ensure that all CleanSpace EX PAPR units are serviced according to the manufacturer's recommendations. Dates of service shall be recorded in the equipment's logbook and shall include a description of the work performed.

6.    The CleanSpace EX PAPR units, that will be used in or inby the last open crosscut, shall not be put into service until MSHA has initially inspected the equipment and determined that it complies with all the terms and conditions of this Order.

7.    Prior to energizing the CleanSpace EX PAPR to be used in or inby the last open crosscut, methane tests must be made in accordance with 30 C.F.R. § 75.323(a).

8.    All hand-held methane detectors shall be MSHA-approved and maintained in permissible and proper operating condition as defined by 30 C.F.R. § 75.320. All methane detectors must provide visual and audible warnings when methane is detected at or above 1.0 percent.

9.    A qualified person as defined in existing 30 C.F.R. § 75.151 shall continuously monitor for methane immediately before and during the use of the CleanSpace EX PAPR in or inby the last open crosscut.

10.    The CleanSpace EX PAPR shall not be used if methane is detected in concentrations at or above 1.0 percent methane. When 1.0 percent or more of methane is detected while the CleanSpace EX PAPR is being used, the equipment shall be de-energized immediately and the equipment withdrawn outby the last open crosscut.

11.    Use only the CleanSpace EX Power Unit, which meets lithium battery safety standard UL 1642 or IEC 62133.
12.    Before each shift when the CleanSpace EX PAPR is to be used, all internal batteries within the power unit assembly must be charged sufficiently so that they are not expected to be replaced on that shift.

13.    The following maintenance and use conditions shall apply to equipment containing lithium-type batteries:

i.    The CleanSpace EX Power Unit may not be disassembled or modified by anyone other than permitted by the manufacturer of the equipment.

ii.    The CleanSpace EX internal battery, contained within the power unit assembly, shall only be charged in areas located outby the last open crosscut in intake air per 30 CFR 75.340 or in an area free of combustible material, readily monitored and located on the surface of the mine and only the manufacturer’s recommended battery chargers may be used such as the CleanSpace EX Battery Charger, Product Code PAF-0066.

iii.    The CleanSpace EX power unit, which contains the internal battery, shall not be exposed to water, allowed to get wet or immersed in liquid. This does not preclude incidental exposure of the power unit assembly.

iv.    The CleanSpace EX PAPR unit, including the internal battery, shall not be used, charged or stored in locations where the manufacturer’s recommended temperature limits are exceeded. The CleanSpace EX PAPR shall not be placed in direct sunlight or used or stored near a source of heat.

v.    The CleanSpace EX PAPR, including the internal battery, shall not be used at the end of its life cycle (i.e., when there is a performance decrease of greater than 20% in battery operated equipment). The power unit containing the internal battery must be disposed of properly.

a.    Follow the manufacturer’s recommendations and instructions. Check and monitor each unit’s run time. Observe and note the run time that a new fully charged battery provides for powering the unit. Record and use this new battery run time as a baseline for determining its service life. Note: The battery run time will vary depending on the product’s configuration and the applications running.
b.    Routinely check the battery’s charge status.
c.    Routinely monitor batteries that are approaching the end of their estimated service life.
d.    Remove battery from service with the following conditions:
1.    The battery run time drops below about 80% of the new battery run time.
2.    The battery charge time increases significantly.
e.    Follow the storage instructions as recommended by the manufacturer. If the instructions were not followed for a battery stored or otherwise unused for an extended period or the battery has no charge remaining, consider it to be damaged. Do not attempt to recharge it or use it. Remove it from service and replace it with a new battery.

14.    Personnel engaged in the use of the CleanSpace EX PAPRs shall be properly trained to recognize the hazards and limitations associated with the use of the equipment in areas where methane could be present. Additionally, personnel shall be trained regarding proper procedures for donning Self-Contained Self Rescuers (SCSRs) during a mine emergency while wearing the CleanSpace EX PAPR. The mine operator shall submit proposed revisions to update the Mine Emergency Evacuation and Firefighting Program of Instruction under 30 CFR § 75.1502.

15.    Within 60 days after this Order becomes final, the operator shall submit proposed revisions for its approved 30 C.F.R. Part 48 training plans to the Mine Safety and Health Enforcement District Manager. These proposed revisions shall specify initial and refresher training regarding the terms and conditions stated in this Decision and Order. When training is conducted on the terms and conditions in this Order, an MSHA Certificate of Training (Form 5000-23) shall be completed. Comments shall be included on the Certificate of Training indicating that the training received was for use of the CleanSpace EX PAPR.

16.    All personnel who will be involved with or affected using the CleanSpace EX PAPRs shall receive training in accordance with 30 C.F.R. § 48.7 on the requirements of this Order within 60 days of the date this Order becomes final. Such training must be completed before any CleanSpace EX PAPR can be used in or inby the last open crosscut. The operator shall keep a record of such training and provide such record to MSHA upon request.

17.    The operator shall provide annual retraining to all personnel who will be involved with or affected using the CleanSpace EX PAPRs in accordance with 30 C.F.R. § 48.8. The operator shall train new miners on the requirements of this Order in accordance with 30 C.F.R. § 48.5 and shall train experienced miners on the requirements of this Order in accordance with 30 C.F.R. § 48.6. The operator shall keep a record of such training and provide such record to MSHA upon request.

18.    The operator shall post this Order in unobstructed locations on the bulletin boards and/or in other conspicuous places where notices to miners are ordinarily posted, for a period of not less than 60 consecutive days.
Unless specifically mentioned herein, nothing in this Order changes or supersedes the requirements otherwise imposed by the Mine Act, other mandatory standards or regulations, or approved plans.

The petitioner shall include the above terms and conditions in the initial and annual refresher training as required in its approved Part 48 training plans to ensure that miners are aware of the stipulations contained in this petition.
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, 201 12th Street South, Arlington, Virginia 22202.
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.

Brian Goepfert 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 20 day of
    March    ,2023, to:

Mr. Josh Robinett    Mr. Eddie Pinegar
Safety Director    Miner’s Representative Crimson Oak Grove Resources, LLC 8800 Oak Grove Mine Road
Adger, Alabama 35023

Robert S. Roark
Mine Safety and Health Specialist

cc:        Mr. James R. West, Mine Safety and Inspection Chief, Alabama Department of Labor, 11 West Oxmoor Road, Ste. 201, Birmingham, AL 35309