OSHA Respirable Crystalline Silica in Construction — 29 CFR 1926.1153

Federal construction safety · Field reference for concrete, masonry, and stone-work contractors

Silica dust causes silicosis, lung cancer, COPD, and kidney disease. The evidence has been solid for a century. What changed in 2016 was OSHA's willingness to regulate a construction-specific standard — 29 CFR 1926.1153 — that set a lower exposure limit, mandated engineering controls for the highest-hazard tasks, and imposed a written-plan and Competent Person structure that treats silica like the health hazard it is. If your crew cuts concrete, drills masonry, cuts engineered stone, sacks dry mortar, demolishes concrete, or breaks up pavement, you are a covered employer. Table 1 is the path most contractors take — if you use it correctly.

The construction standard is 29 CFR 1926.1153, fully effective June 23, 2017 for construction (with delayed full enforcement for certain provisions). The general-industry silica standard at 29 CFR 1910.1053 is similar in structure but works differently on the specified-exposure-control option.

The PEL and the Action Level

The exposure numbers for respirable crystalline silica in construction:

• Permissible Exposure Limit (PEL): 50 micrograms per cubic meter of air (50 μg/m³) averaged over an 8-hour time-weighted average. Cut in half from the previous 100 μg/m³.
• Action Level: 25 μg/m³ — triggers additional obligations including exposure assessment and medical surveillance (under certain conditions).

Two compliance paths

§ 1926.1153 gives the employer two mutually-exclusive compliance approaches for each task.

Option 1: Specified Exposure Control Methods ("Table 1")

Table 1 to § 1926.1153 lists 18 common construction tasks (stationary masonry saws, handheld power saws, handheld and stand-mounted drills, dowel drilling rigs, vehicle-mounted drilling rigs, jackhammers and handheld powered chipping tools, handheld grinders for mortar removal, handheld grinders for uses other than mortar removal, walk-behind saws, drivable saws, rig-mounted core saws, handheld masonry chipping tools, walk-behind milling machines, crushing machines, and heavy equipment and utility vehicles used to abrade or fracture silica-containing materials, among others). For each task, Table 1 specifies:

• The engineering control that must be used (water delivery, enclosed cab, ventilated shrouded tool with HEPA vacuum, etc.).
• The operating procedure requirements (manufacturer's instructions, dust-collection system operation).
• The respiratory protection requirements, with duration triggers (no respirator required for short durations; APF 10 or APF 25 respirator required for longer durations; some tasks require respirators regardless of duration).

An employer that fully and properly implements Table 1 for a task is deemed in compliance with the PEL for that task. No exposure assessment is required. This is the path most construction contractors use.

"Fully and properly" is strict: every element of the Table 1 entry must be followed. Using a saw with water delivery but turning the water off defeats the Table 1 defense. Using a shroud without connecting it to a HEPA-filtered vacuum of adequate CFM defeats the Table 1 defense. Partial Table 1 compliance is not compliance.

Option 2: Alternative Exposure Control Methods

If the employer does not use Table 1 — or for tasks not on Table 1 — the employer must:

• Perform exposure assessment — either through objective data (historic task-specific exposure data from similar operations) or through air monitoring of actual employees performing the task.
• Limit exposure to at or below the PEL — through engineering and work-practice controls, with respiratory protection only where engineering and work practices cannot reduce exposures at or below the PEL.
• Reassess exposures when changes in production, process, or control equipment may result in new or additional exposure at or above the Action Level.

The alternative-method path is the legally available route for atypical tasks but carries substantial documentation and monitoring burdens. Most contractors prefer Table 1.

The written Exposure Control Plan

Every employer covered by § 1926.1153 must prepare and implement a written Exposure Control Plan. The plan must describe:

• The tasks involving exposure to respirable crystalline silica.
• The engineering controls, work practices, and respiratory protection used.
• Procedures used to restrict access to work areas to minimize the number of employees exposed.
• Procedures used to minimize exposures during cleanup, equipment maintenance, and similar activities.

A Competent Person — defined in the standard as an individual capable of identifying existing and predictable silica hazards and with authority to take prompt corrective action — must make frequent and regular inspections of job sites, materials, and equipment to implement the written plan.

Like OSHA Subpart P (excavation) and Subpart L (scaffolding), the silica Competent Person is not certified by OSHA. The employer must be able to demonstrate competence through experience and knowledge of the rule.

Prohibited practices

§ 1926.1153 prohibits certain practices regardless of exposure level:

• Dry sweeping or dry brushing where it could contribute to employee exposure to respirable crystalline silica, unless wet methods and HEPA-filtered vacuuming are not feasible.
• Compressed air to clean clothing or surfaces where it could contribute to employee exposure, unless the compressed air is used in conjunction with a ventilation system that captures the dust cloud, or no alternative method is feasible.

These prohibitions are strict: "saw-dust brush-off" with compressed air is a citation regardless of measured exposure level.

Medical surveillance

When an employee is required to use a respirator for 30 or more days per year due to silica exposure, the employer must offer medical surveillance:

• Initial examination within 30 days of the assignment, including medical and work history, physical examination, chest X-ray, pulmonary function test, TB testing (as indicated), and a questionnaire.
• Periodic examinations every three years (every two years in specific cases).
• Written medical opinion from the Physician or Licensed Health Care Professional (PLHCP).
• Confidential medical records retained for the duration of employment plus 30 years.

The medical surveillance is at no cost to the employee, at a reasonable time and place, and without loss of pay. The PLHCP reports to the employer only recommendations limiting silica exposure — specific diagnostic findings remain confidential.

Training and information

Employers must train each employee covered by § 1926.1153 so that the employee can demonstrate knowledge and understanding of:

• The health hazards of respirable crystalline silica.
• Specific tasks in the workplace that could result in exposure.
• Specific measures the employer has implemented to protect employees.
• The contents of the written Exposure Control Plan.
• The identity of the Competent Person.
• The purpose and description of the medical surveillance program.

Training must be understandable to employees (language and literacy-appropriate) and documented.

Common Table 1 entries and practical controls

Handheld power saws (Table 1 #2)

Engineering control: tool with integrated water delivery that continuously feeds water to the blade, or tool used in a workstation with local exhaust ventilation (dust collection). Operator's respirator is APF 10 indoors or enclosed for > 4 hours/shift.

Handheld and stand-mounted drills (Table 1 #3)

Engineering control: tool with commercially available shroud or cowling with dust collection that has 25 CFM per inch of drill bit, and a HEPA-filtered vacuum. No respirator required if properly used.

Jackhammers and handheld powered chipping tools (Table 1 #6)

Engineering control: water delivery to the tool, or tool equipped with commercially available shroud or cowling with dust collection. Respirator APF 10 for outdoor use < 4 hours/shift, higher durations require escalated respiratory protection.

Walk-behind saws (Table 1 #9)

Engineering control: water delivery that continuously feeds water to the blade. No respirator required for most operational configurations if properly used.

The pattern is clear: water or dust collection, done right, done every time. Missing either defeats the Table 1 defense and throws the employer onto the PEL-compliance path with no assessment in hand.

Enforcement

Silica is one of OSHA's top enforcement priorities in construction. Common citations:

• No written Exposure Control Plan.
• Water system not operating during cutting.
• HEPA vacuum not connected or undersized.
• No Competent Person identified.
• Dry sweeping observed on site.
• Compressed air blow-down of workstations.
• No training records.
• Respiratory protection program absent where respirators are required under Table 1 durations.

Penalties follow OSHA's standard penalty framework (serious, willful, repeat) and can scale quickly on multi-employer sites where multiple trades cut concrete daily.

What this means on site

Silica compliance is a daily operational discipline. Three rules:

• Pick Table 1 for every task you can — and follow every element of the row.
• Write and implement the Exposure Control Plan — not a generic copy-paste, but a plan tied to the actual tasks, equipment, and Competent Person on the site.
• Never dry-sweep silica-containing dust; never blow it off with compressed air — these are per-se violations.

If you are a general contractor relying on subs' compliance, remember the Multi-Employer Worksite policy: the Controlling Employer is responsible for subcontractor violations under certain conditions. Flowdown silica obligations in the subcontract, verify them during pre-shift walks, and document. This is one of the areas OSHA looks at first.

Primary sources for this essay: 29 CFR 1926.1153 (Construction Silica Standard) and Table 1; 81 Fed. Reg. 16286 (March 25, 2016, final rule); OSHA Construction Silica Standard Interim Enforcement Guidance; 29 CFR 1910.1053 (General Industry) for cross-reference. OSHA's Small Entity Compliance Guide for the Silica Standard is the practitioner-facing companion.