Respirable crystalline silica — the fine dust from cutting, grinding, drilling, or crushing stone, concrete, and sand — causes silicosis, lung cancer, and kidney disease. The exposures are invisible and the disease is irreversible, which is why the standards are strict about measurement and controls. Here's what OSHA requires, and an honest note on the mining side.

The OSHA exposure limits

OSHA's silica standards — 29 CFR 1910.1053 (general industry and maritime) and 29 CFR 1926.1153 (construction) — set:

  • A permissible exposure limit (PEL) of 50 µg/m³ of respirable crystalline silica, averaged over an 8-hour day, and
  • An action level of 25 µg/m³, the threshold that triggers monitoring and other obligations.

What the standard asks of you

Beyond the number, the rule is a program:

  • Exposure assessment — determine each worker's exposure, by monitoring or objective data.
  • A written exposure control plan — describe the tasks that create silica exposure and the engineering controls, work practices, and respiratory protection used for each.
  • Engineering controls first — water/wet methods and local exhaust ventilation to keep dust down at the source, before relying on respirators.
  • Medical surveillance — offered to employees exposed at or above the action level for the required number of days per year.
  • Housekeeping, training, and recordkeeping — no dry sweeping or compressed-air cleanup where it disperses dust, plus hazard training and exposure/medical records.

Table 1: the construction shortcut

Construction has a helpful option. Table 1 in 1926.1153 lists common tasks (using a handheld saw, a jackhammer, a core drill, and so on) paired with specified control methods. Follow the Table 1 control fully for a task and you're relieved of separate exposure assessment for it. It's the most practical path for many contractors — but only if you actually run the specified control (the water, the dust collector) as written.

The mining side: watch the effective dates

Historically, mining operated under older, higher silica limits than OSHA's. MSHA has moved to close that gap with a rule aligning miner exposure to the 50 µg/m³ limit. In practice, its implementation has faced compliance-date adjustments and legal challenge, so the honest guidance for operators is: the direction is clear — parity with OSHA at 50 µg/m³ — but confirm the current effective compliance dates for your mine type before you rely on them, because they have moved. Building your dust-control and sampling program now, rather than waiting, is the low-regret move.

Where a program lives or dies

Silica compliance is fundamentally about exposure data and medical follow-through over time — sampling results tied to tasks and people, control plans kept current, and medical surveillance that doesn't lapse. That's a longitudinal records problem, exactly the kind that decays in spreadsheets.

SE Worldwide tracks industrial-hygiene sampling against tasks and workers, keeps the written exposure-control plan and its controls in one place, and drives medical-surveillance scheduling so eligible workers don't fall through. See the health and exposure toolkit — IH, silica, respirators, and 30-year medical-record retention on one spine.

This article is general information about health, safety, and environmental regulations, not legal or compliance advice. Rules change and apply differently by site — verify against the current regulation and your own obligations. See our Terms of Use.