April 15, 2025 - A federal appeals court just gave mine operators a reprieve from its strict new silica rule after temporarily blocking it from going into effect. The Mine Safety and Health Administration (MSHA) had announced on April 9 that it would temporarily delay enforcement of key provisions of its final respirable crystalline silica rule, with a key new deadline set for August 18. But it’s uncertain whether this deadline will have any teeth given the April 11 court order that stays the rule from being enforced on a temporary basis. This delay offers a window for mine operators to regroup and get systems in place in the event enforcement kicks in this summer. Here’s what you need to know – and what steps you should be taking now.

What Just Happened?

MSHA had temporarily paused enforcement of the new silica standards for coal operators on April 9. In its official announcement, the agency cited the need to coordinate with other federal partners – namely OSHA and NIOSH – and to address implementation questions raised by stakeholders, including employers and unions. This announcement, however, left next year’s compliance deadline for metal/non-metal operators in place.

Later last week, however, a federal court blocked enforcement of the silica rule on a temporary basis while it hears a challenge to the rule. In response to a challenge by the National Mining Association (NMA) and other industry groups, the 8th Circuit Court of Appeals issued an order on April 11 that “stays” the rule and prevents it from taking effect until it can consider the issues more fully. It asked MSHA to respond to arguments that the silica rule:

• overreaches the agency’s statutory authority;
• is overly strict;
• is legally flawed;
• would be too costly for employers; and
• would impose technical burdens without adequate justification.

MSHA’s decision to delay enforcement just days later has fueled speculation that the agency may be seeking time to shore up its legal and technical rationale. In fact, the agency took “no position” to the challengers’ request for a stay of the rule.

What’s the New Timeline?

The original enforcement date for coal operators was set for April 14. That’s now changed. Assuming the court order blocking the rule is eventually lifted – and that’s a big if – the agency has set the following revised timetable for the rule:
 

But again, the court order in place now blocks the rule from taking effect on a temporary basis. Because court proceedings are notoriously unpredictable, there is a chance that the rule could be given the green light by the court – meaning mine operators might want to start moving toward full compliance by these new effective dates.

What’s Next in the Litigation?

The next step in the underlying litigation is for the parties to file status reports on June 10. That will provide us all more information about where we can expect the litigation to head. Briefing on the case will continue in September, while MSHA and the Department of Labor reconsider this rule. The court will then evaluate the rulemaking challenge that could address the rule’s substantive requirements at that time.  

What Does the Rule Require?

As covered in our previous Insight, the rule brings MSHA in line with OSHA’s silica standard and reflects a significant expansion in obligations for mine operators. Specifically, the rule:

• Lowers the permissible exposure limit (PEL) for respirable crystalline silica in half, from 100 to 50 micrograms per cubic meter, with an action level at 25 µg/m³.
• Requires air monitoring, employee notification, and exposure tracking.
• Mandates engineering and administrative controls before PPE.
• Requires medical surveillance for miners exposed above the action level for 30+ days/year.
• Imposes new recordkeeping obligations and program audits.

What Should Employers Do Now?

If you have a low risk tolerance level and want to be prepare under the assumption that the rule will go into effect in August, here’s your compliance game plan:

• Audit your silica exposure levels.
  Conduct representative sampling and classify exposure groups now.
• Plan and budget for engineering controls.
  Don’t wait until 2026 to identify feasible dust suppression, ventilation, or process redesign strategies.
• Launch PPE programs where controls are not feasible.
  Ensure respirators meet standards and workers are properly trained and fit-tested.
• Prepare medical surveillance infrastructure.
  Coal operators will need to arrange chest X-rays and spirometry; connect with NIOSH-approved providers now.
• Update documentation.
  Written exposure control plans, sampling records, employee notifications, and training materials should be ready.
• Track MSHA developments.
  Watch for FAQs, guidance, and any updates on litigation outcomes or further enforcement shifts.