1926.303(c): Abrasive Wheel Guards and Work Rests
Bench and floor grinders need safety guards strong enough to withstand a bursting wheel, with wheel exposure limited to 90 degrees, or 125 degrees when work is below the spindle, starting not more than 65 degrees above the spindle. Work rests must be rigid, adjustable and kept no more than 1/8 inch from the wheel. Portable wheels need guards or safety flanges as the rule specifies.
Key takeaways
- 1926.303(c) is part of OSHA's construction standards (29 CFR Part 1926, Subpart I).
- OSHA cited it 20 times in the last 3 years, in 19 inspections, with $26,894 in current penalties.
- Most citations: IN (7), VA (2), IA (2).
- Related part: 1926.303(c)(3) (16 citations).
- Free 5-minute toolbox talk for your crew below.
In this article
What this rule covers
29 CFR 1926.303(c) ("Use of abrasive wheels") is one requirement inside 1926.303 Abrasive wheels and tools, an OSHA construction standard (Part 1926, Subpart I). It includes 13 sub-paragraphs. The official text below is copied word for word from the Electronic Code of Federal Regulations (eCFR). The numbers, injury cases and training on this page show how OSHA enforces it on real job sites.
Official text
(c) Use of abrasive wheels. 20 citations
(1) Floor stand and bench mounted abrasive wheels, used for external grinding, shall be provided with safety guards (protection hoods). The maximum angular exposure of the grinding wheel periphery and sides shall be not more than 90°, except that when work requires contact with the wheel below the horizontal plane of the spindle, the angular exposure shall not exceed 125°. In either case, the exposure shall begin not more than 65° above the horizontal plane of the spindle. Safety guards shall be strong enough to withstand the effect of a bursting wheel.
(2) Floor and bench-mounted grinders shall be provided with work rests which are rigidly supported and readily adjustable. Such work rests shall be kept at a distance not to exceed one-eighth inch from the surface of the wheel.
(3) Cup type wheels used for external grinding shall be protected by either a revolving cup guard or a band type guard in accordance with the provisions of the American National Standards Institute, B7.1-1970 Safety Code for the Use, Care, and Protection of Abrasive Wheels. All other portable abrasive wheels used for external grinding, shall be provided with safety guards (protection hoods) meeting the requirements of paragraph (c)(5) of this section, except as follows: Open (c)(3) 16 citations
(i) When the work location makes it impossible, a wheel equipped with safety flanges, as described in paragraph (c)(6) of this section, shall be used;
(ii) When wheels 2 inches or less in diameter which are securely mounted on the end of a steel mandrel are used.
(4) Portable abrasive wheels used for internal grinding shall be provided with safety flanges (protection flanges) meeting the requirements of paragraph (c)(6) of this section, except as follows: 1 citations
(i) When wheels 2 inches or less in diameter which are securely mounted on the end of a steel mandrel are used;
(ii) If the wheel is entirely within the work being ground while in use.
(5) When safety guards are required, they shall be so mounted as to maintain proper alignment with the wheel, and the guard and its fastenings shall be of sufficient strength to retain fragments of the wheel in case of accidental breakage. The maximum angular exposure of the grinding wheel periphery and sides shall not exceed 180°. 1 citations
(6) When safety flanges are required, they shall be used only with wheels designed to fit the flanges. Only safety flanges, of a type and design and properly assembled so as to ensure that the pieces of the wheel will be retained in case of accidental breakage, shall be used.
(7) All abrasive wheels shall be closely inspected and ring-tested before mounting to ensure that they are free from cracks or defects. 1 citations
(8) Grinding wheels shall fit freely on the spindle and shall not be forced on. The spindle nut shall be tightened only enough to hold the wheel in place.
(9) All employees using abrasive wheels shall be protected by eye protection equipment in accordance with the requirements of subpart E of this part, except when adequate eye protection is afforded by eye shields which are permanently attached to the bench or floor stand. 1 citations
Source: eCFR, text current as of 2026-10-15. Read all of 1926.303.
Where and how often it was cited
| Year | Citations |
|---|---|
| 2023 | 2 |
| 2024 | 8 |
| 2025 | 9 |
| 2026 | 1 |
Top states: IN (7), VA (2), IA (2), MD (1), MN (1)
Largest penalties
| Employer | Location | Penalty for this rule |
|---|---|---|
| BZI CONSTRUCTION LLC | SPARKS, NV | $7,235 |
| GCS ROMAN STEEL WORK LLC | LAFAYETTE, IN | $4,200 |
| RFX2024XEG419X0029 - 3D EPOXY REZ, LLC | PHOENIX, AZ | $3,349 |
| HALEAKALA INVESTMENT CO LTD | HONOLULU, HI | $2,879 |
| MILO MILLER | TITUSVILLE, PA | $2,412 |
Free toolbox talk
A 5-minute crew talk on 1926.303(c), plus alerts when this rule changes. Free.
OSHA interpretation letters
None exist. OSHA has not published a letter of interpretation for 1926.303(c).
Related parts of this rule
- 1926.303(c)(3) 16 citations
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Frequently asked questions
How close must the grinder work rest be to the wheel?
At a distance not to exceed one-eighth inch from the surface of the wheel.
How much of the wheel can be exposed?
Not more than 90 degrees, or not more than 125 degrees when work requires contact below the spindle's horizontal plane, starting not more than 65 degrees above it.
Do portable grinders need guards?
Yes. Portable wheels for external grinding need safety guards, with limited exceptions such as wheels 2 inches or less securely mounted on a steel mandrel.
About this page
Sources
- 29 CFR 1926.303 (eCFR), text current as of 2026-10-15
- U.S. Department of Labor enforcement data: OSHA inspections, citations and accident records, copied nightly; data as of 2026-10-19
3-year window. Federal OSHA only; state-plan rules are not counted. Plain-language text is a summary, not legal advice; the official text controls. Black Belt Safety is not part of OSHA or the Department of Labor.