MSHA opens comments for proposed silica dust rule, removes five outdated rules

The Mine Safety and Health Administration (MSHA) today announced six regulatory changes, issuing a revised silica dust rule proposal and updating five outdated rules.

All six changes will be published in the Nov. 12 edition of the Federal Register.

Silica dust proposal aligns compliance with OSHA standards

The proposed silica dust rule amends the 2024 final rule to better protect the nation’s miners from health hazards associated with exposure to respirable crystalline silica, also known as silica dust or quartz dust.

MSHA said the proposal adds practical, commonsense, risk-based improvements based on OSHA standards to:

• Compliance requirements
• Exposure monitoring
• Medical surveillance
• Recordkeeping
• Respiratory protection

The proposal retains the permissible exposure limit (PEL) for respirable crystalline silica at or below 50 micrograms per cubic meter of air and action level at 25 micrograms.

Several developments after publication of the 2024 final rule led to MSHA’s decision to develop a new proposed rule related to silica dust. These included the U.S. Court of Appeals for the 8th Circuit’s stay of the compliance deadlines in the final rule.

MSHA announced in an April 2026 program information bulletin that it would delay enforcement of the requirements in the 2024 final rule because of the stay, while continuing to enforce existing standards.

Silica dust rule comments open until Jan. 11

After publication of the proposed silica dust rule in the Federal Register, MSHA will welcome public comments and announce the date for an upcoming public hearing. The hearing will be open for online participation.

Comments are due Jan. 11, 2027, or 60 days after the rule’s publication in the Federal Register.

Outdated effective dates and technologies to be removed Dec. 12

MSHA said it is furthering President Trump’s executive order aimed at eliminating unnecessary, outdated, and burdensome regulations by issuing five final rules related to mine safety and health.

The DOL said today’s final rules do not reduce protections for miners because they remove requirements that are no longer applicable to the underground mining industry.

These changes include removing outdated effective dates, requirements for outdated technology that is no longer used, and duplicative requirements.

MSHA issued final rules in the following areas:

1. Permissible lamps - Removes duplicative requirements for electric cap lamps and other electric lamps in underground coal mines.
2. Diesel particulate matter - Eliminates outdated requirements for diesel particulate matter personal exposure limits for underground metal and nonmetal mines.
3. Installation of foam generator systems in underground coal mines - Removes requirements that are no longer applicable to underground coal mines.
4. Electrical face equipment in coal seams above the water table - Eliminates regulatory requirements because all underground coal mines are treated similarly, regardless of location relative to the water table.
5. Final mining of pillars - Removes regulatory requirements on the subject as the practice of final mining of pillars with one mine opening is no longer used.

All five final rules will be effective on Dec. 12, or 30 days after their publication in the Federal Register.

Four outdated rules updated in June

Earlier this year, MSHA published four final deregulatory rules:

1. Approved conveyor belts in underground coal mines - Removed outdated effective dates regarding flame-resistance approval requirements for conveyor belts which have not been applicable since 2018.
2. Diesel particulate matter in underground coal mines - Removed outdated effective dates that are no longer applicable from diesel particulate matter emission limits.
3. Blacksmith Shops - Eliminated outdated requirements for blacksmith shops located at surface areas of underground metal and nonmetal mines because the outdated technology is no longer used.
4. Flame safety lamps in underground coal mines - Removed flame safety lamps from the list of permissible electric face equipment that can be operated in underground coal mines because the outdated technology is no longer used.