OSHA Written Silica Exposure Control Plan Requirements

OSHA’s silica standards require a written exposure control plan whenever any employee’s exposure to respirable crystalline silica could reach the action level of 25 micrograms per cubic meter of air, measured as an eight-hour average. The requirement lives in two parallel regulations: 29 CFR 1926.1153 for construction and 29 CFR 1910.1053 for general industry and maritime. The plan is a working document that identifies every silica-generating task, the controls used for each one, the housekeeping methods on site, and, for construction, how access to dusty areas is limited.¹

When the Plan Is Required

The trigger is exposure, not industry or job title. If any covered employee’s exposure could foreseeably reach 25 μg/m³ as an eight-hour time-weighted average, the standard applies and the written plan is mandatory. If exposures will stay below that threshold under all foreseeable conditions without any controls in place, none of the standard’s requirements apply.²

The permissible exposure limit (PEL) sits higher, at 50 μg/m³ over the same eight-hour average, and no employee may be exposed above that level. The 25 μg/m³ action level is the lower threshold that triggers monitoring, medical surveillance, and the rest of the standard’s protective requirements.³ The plan itself is a core requirement of the regulation; there is no separate trigger for it.¹

Construction employers can follow either of two compliance paths, and the written plan is required under both. Table 1 lists common silica-generating tasks paired with specific engineering controls, work practices, and respiratory protection; fully implementing Table 1 for a listed task relieves the employer of separate air-monitoring obligations. The alternative exposure control methods path applies when a task is not on Table 1 or when the employer does not fully implement Table 1’s specified controls, and it requires assessment through air monitoring or objective data.¹

What the Written Plan Must Contain

For construction, the written plan must include four elements:

A description of every task in the workplace that involves exposure to silica.
A description of the engineering controls, work practices, and respiratory protection used for each listed task.
A description of the housekeeping measures used to limit exposure to silica dust.
A description of the procedures used to restrict access to work areas where silica dust is present, including exposure from other employers or sole proprietors on the site.

The general industry standard requires the same first three elements. It does not include access restriction procedures as a mandatory plan component; general industry handles access through a separate “regulated area” requirement described below.³

The plan should be specific enough that someone unfamiliar with the site could read it and understand what controls apply to which task. A phrase like “use dust suppression” does not meet the standard. The plan needs to identify the actual equipment (wet-cutting saws with integrated water feeds, HEPA-filtered vacuum attachments on grinders, enclosed cabs on crushing machines) and connect each item to the task it controls.

Housekeeping Rules the Plan Must Reflect

Improper cleanup is one of the fastest ways to re-expose workers to settled silica dust, which is why housekeeping is its own required element. Both standards prohibit dry sweeping and dry brushing where those activities could contribute to silica exposure, unless wet sweeping or HEPA-filtered vacuuming is not feasible.³

Compressed air is also prohibited for cleaning surfaces or clothing unless it is paired with a ventilation system that effectively captures the dust cloud it creates. Rigging that kind of ventilation around a blow-off operation is rarely practical, so most sites ban compressed-air cleanup for silica dust outright. The written plan should describe the approved cleaning methods the site actually uses and state clearly what is off-limits.

Competent Person (Construction Only)

The construction standard requires the employer to designate a competent person who makes frequent and regular inspections of jobsites, materials, and equipment to carry out the written exposure control plan. The regulation defines this person as someone capable of identifying existing and foreseeable silica hazards and authorized to take prompt corrective action to eliminate or minimize them.¹

The competent person’s name does not have to appear in the written plan itself. OSHA has stated that it expects the identity of the competent person to change frequently on construction sites, so the plan does not need to include a specific name. The employer still must designate someone, and training rules separately require employees to be able to identify the competent person on their jobsite.⁴

The general industry standard has no competent person requirement.⁵

Access Restriction Versus Regulated Areas

How employers limit who enters high-exposure zones is the point where the two standards diverge most sharply.

Construction Access Restriction

The construction standard requires the written plan to describe the procedures used to restrict access to work areas where silica dust is present, including exposure generated by other employers or sole proprietors on the same site. The regulation does not dictate specific methods. Physical barriers around cutting and grinding areas, scheduling heavy dust work during off-hours, and posted warnings are common approaches. What matters is that the plan documents whatever procedures are actually used and that those procedures effectively minimize the number of people exposed.¹

General Industry Regulated Areas

The general industry standard is more prescriptive. Employers must establish a formal “regulated area” wherever any employee’s exposure is or could reasonably be expected to exceed the PEL of 50 μg/m³. The regulated area must be visibly demarcated, and signs must be posted at every entrance bearing this specific language:

DANGER
RESPIRABLE CRYSTALLINE SILICA
MAY CAUSE CANCER
CAUSES DAMAGE TO LUNGS
WEAR RESPIRATORY PROTECTION IN THIS AREA
AUTHORIZED PERSONNEL ONLY⁶

Access is limited to people whose work duties require them to be there, employee representatives observing monitoring, and OSHA personnel. Everyone entering must wear appropriate respiratory protection.³

Multi-Employer Construction Sites

Silica dust does not respect the boundary between one subcontractor’s scope and another’s. Each construction employer must factor in silica exposure generated by other contractors when determining whether its own employees’ exposures could reach the action level.² If a concrete cutter is generating dust fifty feet from your crew, that exposure counts, and the plan’s access restriction procedures must address it. An employer can avoid accounting for another contractor’s dust only when it can demonstrate, through the nature or timing of the work, that its employees will not be exposed to that dust at all.

Annual Review and Where the Plan Must Live

The written plan must be reviewed and evaluated for effectiveness at least once a year and updated as necessary. The annual review should account for new equipment, different materials, changes in work methods, and any shifts in personnel that could affect exposure levels. If a change happens mid-year that could create new exposures at or above the action level, the plan needs to be updated at that point rather than waiting for the yearly review.⁷

The plan must be readily available for examination and copying by any covered employee, their designated representatives, and OSHA or NIOSH officials, upon request. “Readily available” means an OSHA compliance officer who walks onto your site should be able to see it promptly. A plan that exists only on a corporate server three states away does not satisfy this. Keep a current copy wherever the silica-generating work is being performed.³

Related Obligations the Plan Sits Alongside

The written plan is one requirement inside a larger standard. A compliant silica program also has to include training, medical surveillance for employees exposed at or above the action level for 30 or more days per year, and recordkeeping for air monitoring, objective data, and medical exams.

Employee training must cover the health hazards of silica exposure, the specific tasks on site that could create exposure, the controls and respiratory protection in use, the contents of the standard, and the medical surveillance program. Construction training must also identify the competent person on the jobsite.⁴ The silica standard does not explicitly require training records, but the recordkeeping and exposure records that are required must be maintained under 29 CFR 1910.1020, with exposure records kept for 30 years and medical records for the duration of employment plus 30 years.⁸

Medical exams under the standard produce two separate documents: a full written medical report to the employee, and a much narrower written medical opinion to the employer containing only the exam date, confirmation that the exam met the standard’s requirements, and any respirator-use limitations. The employer does not see the employee’s full medical details unless the employee provides written authorization.³

Penalties for a Missing or Deficient Plan

Failing to maintain a required written exposure control plan can result in OSHA citations. Following the most recent inflation adjustment effective January 2025, the maximum penalties per violation are:

Serious violation: up to $16,550
Other-than-serious violation: up to $16,550
Willful or repeated violation: up to $165,514
Failure to abate: up to $16,550 per day beyond the abatement deadline

⁹

These figures are adjusted annually for inflation. A missing or incomplete plan is rarely the only violation OSHA finds on a silica-focused inspection; citations for inadequate engineering controls, missing medical surveillance, or lack of training typically travel with it, and the combined penalty can climb well into six figures.

1
eCFR. 29 CFR 1926.1153 – Respirable Crystalline Silica
2
Occupational Safety and Health Administration. Frequently Asked Questions for the Construction Industry
3
Occupational Safety and Health Administration. 29 CFR 1910.1053 – Respirable Crystalline Silica
4
Occupational Safety and Health Administration. 29 CFR 1926.1153 – Respirable Crystalline Silica
5
eCFR. 29 CFR 1910.1053 – Respirable Crystalline Silica
6
Occupational Safety and Health Administration. Small Entity Compliance Guide for the Respirable Crystalline Silica Standard for General Industry and Maritime
7
Occupational Safety and Health Administration. Small Entity Compliance Guide for the Respirable Crystalline Silica Standard for Construction
8
Occupational Safety and Health Administration. 29 CFR 1910.1020 – Access to Employee Exposure and Medical Records
9
Occupational Safety and Health Administration. OSHA Penalties