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Short answer
Under OSHA’s eye and face protection rule, 29 CFR 1910.133(a)(2), an employer must ensure that employees use eye protection that provides side protection when there is a hazard from flying objects. Detachable side protectors, such as clip-on or slide-on side shields, are acceptable if they meet the requirements of the section. The duty is tied to a flying-object hazard, not to every task where glasses are worn.
Definition and scope
Side shields are the protective panels at the temples of safety glasses that extend protection to the sides of the eye area. They come either built into the frame or as detachable clip-on or slide-on parts. This page covers what the federal workplace rule says about them and what that means for a laboratory or clinic’s written safety documents. It does not cover splash or chemical-vapor protection, which is a different hazard (see what safety goggles are), or prescription lenses, covered in prescription safety glasses and ANSI Z87.1.
This is general regulatory information for lab and clinic staff, not a hazard assessment for any particular workplace.
What 29 CFR 1910.133(a)(2) says
Paragraph (a)(2) of 1910.133 has two sentences that matter here. The first requires that each affected employee use “eye protection that provides side protection when there is a hazard from flying objects.” The second accepts detachable side protectors, such as clip-on or slide-on side shields, that meet the pertinent requirements of the section.
Three neighbouring paragraphs bear on the same glasses:
- (a)(1) is the general duty to use appropriate eye or face protection against hazards from flying particles, molten metal, liquid chemicals, acids or caustic liquids, chemical gases or vapors, and potentially injurious light radiation.
- (a)(4) requires eye and face PPE to be distinctly marked to facilitate identification of the manufacturer.
- (b)(1) says protective eye and face devices must comply with one of three consensus standards: ANSI/ISEA Z87.1-2010, ANSI Z87.1-2003, or ANSI Z87.1-1989 (R-1998). Paragraph (b)(2) also accepts devices the employer demonstrates are at least as effective.
Detachable versus permanent side shields
OSHA answered this question directly in a standard interpretation letter dated January 29, 2007, titled “Detachable vs. permanent side shields for safety glasses; modifications to safety glasses.” Its points, in OSHA’s words where quoted:
- The standard allows “Detachable side protectors (e.g., clip-on or slide-on side shields)” when they meet the requirements, and the letter confirms that reading.
- “Employers can require their employees to have protection above and beyond the OSHA standard(s).” Requiring permanent, built-in side shields is therefore an employer policy choice, not something the OSHA rule demands in itself.
- “Any modification made to the glasses would need to meet the specifications in the aforementioned ANSI standard” to comply with OSHA.
The letter is an older interpretation: it predates the ANSI/ISEA Z87.1-2010 edition now listed first in (b)(1), so treat it as OSHA’s reading of the principle rather than of the current edition list.
Where it matters for labs and clinics
The rule text supports a short checklist that a lab manager, safety officer or clinic supervisor can run against their own written hazard assessment. Each line below traces to the paragraph shown.
| Question to ask | Rule it traces to |
|---|---|
| Does the task have a flying-object hazard (the condition that triggers side protection)? | 1910.133(a)(2) |
| If yes, does the eyewear provide side protection, either built in or as a detachable clip-on or slide-on shield that meets the section’s requirements? | 1910.133(a)(2) |
| Is the eyewear marked so the manufacturer can be identified? | 1910.133(a)(4) |
| Does the device comply with one of the listed Z87.1 editions, or has the employer demonstrated equal effectiveness? | 1910.133(b)(1), (b)(2) |
| Has anyone altered the side shields or frames (for example, painting them)? | OSHA letter, 2007-01-29 |
| Is a stricter local policy (for example, permanent side shields everywhere) written down as employer policy rather than described as an OSHA rule? | OSHA letter, 2007-01-29 |
The hazard determination itself belongs in the written assessment described in PPE hazard assessment and written certification; the broader rule is summarised in the OSHA PPE standard guide. For how eyewear fits alongside other protective items, see what lab PPE is.
Common misunderstandings
“Side shields protect against splashes”
Paragraph (a)(2) states the side-protection duty in terms of flying objects. Liquid chemicals and chemical vapors are listed separately in (a)(1) as hazards that need appropriate protection. Glasses with side shields leave gaps that goggles do not; the site’s comparison of face shields and safety goggles and the guide to PPE for chemical handling cover that boundary.
“OSHA requires permanent side shields”
It does not. The rule expressly accepts detachable clip-on or slide-on side protectors. Permanent shields can be an employer requirement under the 2007 letter’s reading, but that is policy, not the regulation.
“Any glasses with shields are fine”
The rule still requires manufacturer identification marking and compliance with a listed consensus standard or demonstrated equal effectiveness. OSHA’s 2007 letter adds that any modification made to the glasses would need to meet the specifications in the ANSI standard.
FAQ
Are clip-on side shields allowed under OSHA?
Yes. 1910.133(a)(2) says detachable side protectors, such as clip-on or slide-on side shields, meeting the pertinent requirements of the section are acceptable.
When does OSHA require side protection on safety glasses?
When there is a hazard from flying objects. The employer must ensure affected employees use eye protection that provides side protection in that situation.
Can an employer require permanent side shields?
Yes. According to OSHA’s 2007 interpretation letter, employers can require protection above and beyond the OSHA standards.
Are prescription glasses with side shields covered by a different rule?
Prescription wearers are addressed separately in 1910.133(a)(3). See the guide on prescription safety glasses and ANSI Z87.1.
Sources
- OSHA, 29 CFR 1910.133, Eye and face protection, paragraphs (a)(1)-(a)(4) and (b)(1)-(b)(2): https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.133 (checked 2026-10-30).
- OSHA standard interpretation, January 29, 2007, “Detachable vs. permanent side shields for safety glasses; modifications to safety glasses”: https://www.osha.gov/laws-regs/standardinterpretations/2007-01-29 (checked 2026-10-30).
