Underground mining operations pose a number of hazards to miners even when mine operators implement and exercise the utmost of safety precautions. Some of the more common and serious hazards in an underground mine are the dangers of being pinned, crushed, or struck by mobile equipment which could lead to serious injuries or death. These dangers are especially prevalent in underground coal mines where miners work around mobile equipment in tight quarters and with limited visibility. MSHA believes that many of these accidents could be prevented by the installation of proximity detection systems (“PDS”) on mobile machinery.

According to data released by MSHA, PDS devices could have prevented 42 fatalities and 179 injuries resulting from pinning, crushing, and striking accidents involving scoops and coal haulage equipment in underground coal mines from 1984 to 2014. Between 2010 and 2014 alone, 41 such accidents, including 9 fatalities, could have been avoided by PDS devices. The years 2013 and 2014 alone saw four fatalities caused by accidents involving scoops and coal haulage equipment in underground coal mines, despite an MSHA initiative started in 2010 to encourage mine operators to train underground coal miners to exercise caution when working around mobile machines.

It was against this backdrop that MSHA issued a proposed rule on September 2, 2015 that would require underground coal mine operators to install and maintain PDS devices on scoops and coal haulage equipment on working sections of underground coal mines. Although not currently applicable to the metal/not-metal sector, MSHA is looking at the potential application of the rule to underground metal/non-metal mines. MSHA’s proposed rule follows a similar rule finalized and published by MSHA on January 15, 2015 requiring the installation and maintenance of PDS devices on continuous mining machines in underground coal mines.

The proposed rule for scoops and coal haulage equipment would be phased in over a period of eight to 36 months depending upon certain factors. The rule, when fully phased in, would require that certain MSHA-approved PDS devices be installed on all scoops and coal haulage equipment used on working sections. The PDS devices must be monitored and maintained to ensure they function properly at all times. Operators will be required to provide training to equipment operators, employees who install and maintain the devices, and all miners who work around the machines that are subject to the proposed rule. An analysis of the most significant provisions of the proposed rule is set forth below.

Applicability of the Rule

The proposed rule would eventually require that PDS devices be installed on all scoops and coal haulage machines on working sections of all underground coal mines. Both diesel and electric-powered scoops would fall within the scope of the rule. Coal haulage machines would include shuttle cars, diesel and battery-powered ram cars, and continuous haulage systems. The rule would apply to production and maintenance shifts. Long wall sections would be excepted from the rule because scoops and coal haulage equipment are not routinely used on long wall sections.

Although not currently included within the scope of the rule as proposed, MSHA is seeking information and data addressing whether the subject equipment does, in fact, pose hazards to miners on long wall sections such that proximity detection should be required there as well. MSHA is also seeking comments on whether the proposed rule should be extended to require PDS devices on scoops and coal haulage machines operated off the working section. Additionally, MSHA is seeking comment on whether PDS devices should be required for other types of underground mobile equipment, including loading machines, roof bolting machines, and feeder breakers.

Requirements for Proximity Detection Systems

PDS devices installed pursuant to the rule would have to be approved by MSHA. There are currently four PDS devices that have been approved for use in underground coal mines in relation to the existing requirement for continuous miners. All currently approved devices consist of a machine-mounted component and a component worn by the miner ("miner-wearable component"). The proposed rule would require that operators provide a miner-wearable component to all miners on all working sections of a mine where such devices are used, with the exception of those working on a long wall section. The operator of the machine would also be excepted because the machine would not function if the PDS device prevents the machine from moving when the operator is on the machine. 

The proposed rule would require that PDS devices installed pursuant to the rule cause a machine to stop before contacting a miner. The PDS device must stop all movement of the machine, including tramming, conveyer chain movement, raising and lowering of the bucket of the scoop, etc. The rule takes a performance-based approach focused on stopping the machine before contacting a miner, rather than prescribing how the result must be achieved such as a requirement that the machine be stopped within a certain distance of the miner. Under the rule as currently proposed, the mine operator would be responsible for programming the PDS device to activate in time to stop the machine before contacting the miner.

PDS devices would also have to provide visual and audible warnings to miners before the machine is close enough to be stopped by the PDS so that miners in the path of the machine can make an effort to get out of the way. A visual and audible warning would be required on the miner-wearable component of the PDS to alter the miner in the path of the machine and a visual signal on the machine-mounted component to alert the operator that someone is in his path. The signals must be distinguishable from other signals.

The rule would also require that PDS devices be installed in a manner that prevents interference that would adversely affect the performance of any of the mine’s electrical systems.

Required Training

Existing Part 48 would require the operator to provide new task training for miners working around the equipment covered by the rule as PDS devices are phased in. Operators would need to provide training on safety issues that could arise during the phase in, including the fact that PDS devices may have been installed on some machines but not others. Once the PDS devices are installed, miners working around mobile equipment would also need to be trained on new and unfamiliar tasks such as new work positions, new machine movements, and new visual and auditory signals. Machine operators would also have to be trained on new operating procedures and other changes in the operation of the machines resulting from installation of the PDS devices.

Those charged with installing and maintaining the PDS devices would have to be trained to do so, in addition to any new task training required for them by existing Part 48. MSHA has stated that appropriate training topics may include adjusting detection zones, trouble-shooting electrical connections, and replacing and adjusting machine-mounted and miner-wearable components. It is anticipated that operators would send one or more of its employees charged with installation and maintenance of the PDS devices to receive “train the trainer” training from PDS manufacturers. Those employees would then train others in the company.

Inspections and Maintenance

The new rule would require that PDS devices be installed and maintained in proper operating condition by a person trained in the installation and maintenance of the system. The mine operator must be able to demonstrate that the PDS device has, in fact, been installed and maintained in proper operating condition. To ensure that the system is operating properly, the mine operator must designate someone to perform checks of the PDS devices before entering the working section to ensure that the machine-mounted components are in place and the system is functioning properly. The miner-wearable components must also be checked before miners enter the working section. Checks similar to the check that a miner performs on his cap light will likely be sufficient. Other existing regulations would also require that the PDS devices be subject to weekly inspections.

The rule would also require that the machine mounted components include a visual signal on the machine to indicate whether the machine-mounted components are functioning properly. A PDS would also be required to prevent movement of the machine when the system is malfunctioning. If the machine needs to be relocated to a safer area for repairs, however, the proposed rule would allow this safety feature to be overridden, provided that a visual or audio signal, distinguishable from other signals, is provided during such movement.

Phase-in Schedule

The proposed phase in schedule is the same as the phase-in schedule included in the final rule for continuous miners. Coal hauling machines and scoops manufactured after the effective date of a final rule would be required to meet the rule's requirements no later than 8 months after the effective date of the final rule. Such machines would have to meet the requirements in this section when placed into an underground coal mine.

Coal hauling machines or scoops manufactured and already equipped with a proximity detection system on or before the effective date of a final rule would be required to meet the rule's requirements no later than 8 months after the effective date of the final rule if necessary modifications can be made underground. Such machines would have 36 months after the effective date of the final rule to meet the new requirements when the existing proximity detection system cannot be modified underground or needs replaced.

A PDS meeting the proposed requirements would have to be installed on coal hauling machines or scoops not already equipped with a PDS within 36 month of the effective date of a final rule.

Metal/Nonmetal Application

Although the proposed rule would not apply to underground metal/nonmetal mines, MSHA is considering application of the rule to such mines and seeking public comment on the same. The comment period is set to close on December 15, 2015. Comments have been sparse. At least two industry representatives have commented in opposition to metal/nonmetal application. They have argued that a proximity detection rule is unnecessary in the metal/nonmetal sectors due to differences between the environments encountered in underground metal/nonmetal mines as opposed to underground coal mines. For instance, miners in underground metal/nonmetal mines work in workspaces that are more wide open with better visibility. The industry representatives also commented that more research and development needs to occur to develop PDS devices that meet the specific needs of metal/nonmetal mines and the equipment used therein.

Even if this proposed rule is not made applicable to underground metal/nonmetal mines, MSHA may eventually promulgate a proximity detection rule that applies to such mines given its recent emphasis on proximity detection and its recently heightened focus on safety in the metal/nonmetal sector.

Coal operators should monitor this proposed rulemaking closely and be prepared to meet its requirements in the near future. Experience with the similar existing requirements for continuous miners should be helpful in that regard. Operators of underground metal/nonmetal mines should also keep a close eye on developments in MSHA’s efforts regarding proximity detection and be prepared for similar requirements applicable to their operations at some point in the future.