MSHA’s 18 Proposals: Aggregate Impacts
On July 1, 2025, MSHA proposed 18 rule changes spanning training, plans, diesel controls, and electronic equipment, with comments due July 31. The key question for operators: what actually touches aggregate quarries versus coal-only changes?
Q: Which of the 18 proposals specifically affect aggregate operations vs. coal mines?
Sort the set into three buckets: coal-only items; rules that apply to all mines; and underground metal/nonmetal (MNM) proposals. Aggregates are largely surface MNM with silica risks, not methane or permissible equipment issues.
Bottom line: Most of the 18 target coal (e.g., conveyor belt approvals, diesel limits for coal, permissible equipment and lamps, pillar mining). Aggregate operations should focus on the all-mine proposals (electronic hazard communication access, electronic surveying in high-hazard areas, aerial tramways), training-governance changes that apply to surface and underground mines, and—if applicable—underground MNM items on diesel particulate and limited PAPR use.
Our position: Based on MSHA’s summaries and trade analyses, we recommend prioritizing silica program execution for all sites, monitoring the three all-mine proposals, and—only if you have underground MNM—preparing for the reaffirmed diesel particulate limit (160 TC µg/m³) and potential PAPR allowances. Here’s why: these are the proposals most likely to change day-to-day aggregate operations and budgets; most coal-focused items will not. What remains unknown: the final scope/effective dates of all-mine proposals, MSHA’s silica enforcement posture after fall 2025, and how broadly training-governance changes will be applied to MNM.
Three questions to assess your exposure:
1. Do any of your 40 sites operate underground MNM?
→ If YES: Plan for the 160 TC µg/m³ diesel particulate limit and evaluate nonpermissible PAPR allowances.
→ If NO: Deprioritize underground diesel and PAPR rulemaking for now.
→ DON’T KNOW: Check each site’s mine plan and MSHA listing to confirm underground status.
→ Framework: Underground MNM triggers diesel particulate and equipment rules irrelevant to surface quarries.
2. Do you use electronic hazard communication (safety data sheets), electronic surveying in potentially hazardous atmospheres, or run aerial tramways?
→ If YES: Assign an owner to track these all-mine proposals and budget for system/equipment updates.
→ If NO: Maintain a light monitor posture and document why no changes are expected.
→ DON’T KNOW: Ask site managers and vendors for current systems and equipment lists.
→ Framework: These proposals are cross-commodity and could drive IT and capital adjustments.
3. Are any roles at or above the silica action level (25 µg/m³) or near the 50 µg/m³ legal limit?
→ If YES: Accelerate controls, exposure monitoring, and respiratory program readiness despite enforcement pauses.
→ If NO: Maintain baseline sampling and housekeeping and focus resources on the all-mine proposals.
→ Framework: Silica is already a final rule for all mines and will drive inspections and costs.
What remains unknown: Which proposals ultimately finalize as all-mine versus coal-only; exact effective dates and transition periods; MSHA’s silica enforcement timeline and any 2026 milestones for MNM.
Priority level: PREPARE NOW - While many items are coal-only, silica and the all-mine proposals require planning before 2026.
Recommended actions:
☐ Within 60 days, map each site: surface vs underground, electronic HazCom use, electronic surveying, aerial tramways.
☐ By year-end, lock a silica plan: exposure baseline, engineering controls, and procurement for sampling/respirators.
☐ Within 60 days, assign an owner to track all-mine proposals and hold budget placeholders.
☐ Brief leadership that coal-only items are low priority for aggregates unless operations change.
Next check-in: Fall 2025 or upon MSHA issuance of final rule texts affecting all mines.
