OSHA Silica Table 1 Task Lookup
Table 1 of the OSHA silica standard names eighteen construction tasks and, for each one, the engineering control, the work practice and the respirator required. Pick your task, where it is done and how long the crew spends on Table 1 tasks in total, and this page returns the specified method in OSHA's own words along with the required assigned protection factor. It also tells you when Table 1 stops covering you and paragraph (d) takes over.
Results are estimates for planning purposes and do not replace a competent person's evaluation or an engineer's design. Follow the OSHA standards that apply to your work and your employer's written program.
How Table 1 works
29 CFR 1926.1153 gives construction employers two routes to compliance. Table 1, in paragraph (c), names eighteen equipment/task entries and, for each, the engineering control, the work practice and the respirator to use. Paragraph (c)(1) is the bargain: “For each employee engaged in a task identified on Table 1, the employer shall fully and properly implement the engineering controls, work practices, and respiratory protection specified for the task on Table 1, unless the employer assesses and limits the exposure of the employee to respirable crystalline silica in accordance with paragraph (d) of this section.”
Do that, and you skip the exposure assessment for those tasks. Paragraph (e)(3) adds that you are then treated as complying with the respirator selection requirements of 29 CFR 1910.134(d)(1)(iii) and (d)(3) for silica. Fall short of any element of the specified method and Table 1 stops applying: paragraph (d) takes over, with the 50 µg/m³ permissible exposure limit as an 8-hour TWA and an exposure assessment through the performance option or the scheduled monitoring option.
What rides along with every Table 1 method
Paragraph (c)(2) attaches conditions to the whole table:
- Indoors or in an enclosed area — provide a means of exhaust as needed to minimize the accumulation of visible airborne dust.
- Wet methods — apply water at flow rates sufficient to minimize the release of visible dust. A trickle at the blade is not a wet method.
- Enclosed cab or booth — kept as free as practicable from settled dust; door seals and closing mechanisms working properly; gaskets and seals in good condition; under positive pressure through continuous delivery of fresh air; intake air filtered at 95% efficiency in the 0.3–10.0 µm range (MERV-16 or better); and heating and cooling capabilities.
And outside the table entirely: the written exposure control plan of paragraph (g), the housekeeping prohibitions of (f), hazard communication and training under (i), medical surveillance under (h) for anyone required to wear a respirator 30 or more days a year, and recordkeeping under (j).
The numbers that matter
| Figure | Value | Paragraph |
|---|---|---|
| Scope threshold — below this under any foreseeable conditions, the standard does not apply | 25 µg/m³, 8-hour TWA | (a) |
| Action level | 25 µg/m³, 8-hour TWA | (b) |
| Permissible exposure limit (PEL) | 50 µg/m³, 8-hour TWA | (d)(1) |
| Table 1 respirator column switch | 4 hours, all Table 1 tasks combined | (c)(3) |
| Medical surveillance trigger | Respirator required 30 or more days per year | (h)(1)(i) |
| HEPA filter | At least 99.97% efficient on 0.3 µm mono-dispersed particles | (b) |
| Dust collector filter, most entries | 99% or greater efficiency | Table 1 |
| Grinder dust collector airflow | 25 cfm or greater per inch of wheel diameter | Table 1 (xi), (xii) |
Assigned protection factors come from Table 1 of 29 CFR 1910.134: an APF 10 is a half-mask air-purifying respirator, and an APF 25 is a powered air-purifying respirator with a loose-fitting facepiece or hood, or a supplied-air respirator in that class. In Table 1 of the silica standard, only tuckpointing for more than four hours per shift calls for APF 25. Whenever a respirator is required, 1926.1153(e)(2) requires a full respiratory protection program under 1910.134 — written program, fit testing, medical evaluation and training.
Table 1 is a construction rule. General industry and maritime work under 29 CFR 1910.1053, which shares the 50 and 25 µg/m³ figures but has no table of specified methods.
How it's calculated
- Respirator required
Table 1 entry + location + total Table 1 hours this shift → specified controls and minimum APFThe table is a lookup, not a calculation: the values returned are the ones printed in 29 CFR 1926.1153 Table 1.- The four-hour rule
total duration of all Table 1 tasks combined > 4 h → the '>4 hours/shift' column applies to every task29 CFR 1926.1153(c)(3), word for word. Two hours of sawing plus three hours of chipping is five hours for this purpose.
Frequently asked questions
Sources & references
- 29 CFR 1926.1153 — Respirable crystalline silica (construction): Table 1 at paragraph (c), the PEL at (d)(1), the written plan at (g)
- OSHA — Crystalline Silica Rulemaking: construction compliance materials
- 29 CFR 1910.134 — Respiratory protection, including the assigned protection factors of Table 1 of that section
Content checked against these sources — last reviewed August 28, 2026.