What Safety Glasses Do I Need for a CO₂ Laser?

If you are working with a CO₂ laser, your laser safety eyewear must provide protection at the actual wavelength produced by your laser.

Many industrial CO₂ lasers operate at or near 10,600 nm (10.6 µm) in the infrared portion of the electromagnetic spectrum. However, not all CO₂ lasers operate at exactly 10,600 nm.

Before selecting eyewear, always verify the operating wavelength or wavelength range specified by the laser manufacturer.

The protection range of the eyewear must include that wavelength.

Laser safety eyewear is wavelength-specific.

A pair of glasses that provides excellent protection for a 1064 nm fiber laser, for example, should not be assumed to provide protection for a CO₂ laser operating around 10 µm.

Similarly, you should not select eyewear simply because it is marketed as "CO₂ laser safety glasses."

Instead, compare the wavelength listed for your laser with the wavelength protection marked on the eyewear.

For example, if your laser operates at 10,600 nm, the eyewear's specified protection range must include 10,600 nm. If the laser operates at a different CO₂ wavelength, that wavelength must also fall within the eyewear's rated protection range.

The laser wavelength and the eyewear protection range must match.

Optical density describes how strongly a filter attenuates laser radiation at a particular wavelength.

See this video on how to read Optical Density Notation as well as this article:

Because OD is logarithmic:

Importantly, an OD value has meaning only when associated with a wavelength or wavelength range.

For example, eyewear labeled OD 6+ @ 10,600 nm is providing that level of attenuation at 10,600 nm. An OD 6 rating at an unrelated wavelength does not establish protection against that laser.

A common question is:

"I have a 100 W CO₂ laser. What OD do I need?"

Or:

"I have a 1,000 W CO₂ laser. What glasses should I use?"

Laser power is important, but wattage alone is not enough to determine the required optical density.

The potential exposure depends on factors beyond the laser's rated output power, including:

The required OD is ultimately based on reducing the potential exposure at the eye to an acceptable level.

Two CO₂ laser systems with the same rated wattage can therefore have different exposure conditions and potentially different eyewear requirements.

OSHA specifically addresses wavelength and optical density when discussing laser protective eyewear.

Under 29 CFR 1926.102(c)(2)(i), OSHA requires suitable laser safety goggles that protect for the specific wavelength of the laser and have an optical density adequate for the energy involved.

OSHA also requires protective goggles to identify:

The important takeaway is that laser eyewear selection is not simply:

Laser wattage → eyewear

Instead, the eyewear must provide appropriate protection for both the actual laser wavelength and the potential exposure.

The required optical density should be determined as part of the laser hazard evaluation. For more information on a hazard evaluation (and the difference between classification) see the video below.

For Class 3B and Class 4 laser systems, this is typically performed or approved by the organization's Laser Safety Officer (LSO) or another qualified laser safety professional.

The evaluation considers the laser parameters and reasonably foreseeable exposure conditions to determine the protection required.

The Laser Institute of America (LIA) provides an online Optical Density Calculator that can be used as a resource when evaluating laser eyewear requirements:

LIA Optical Density Calculator:
​https://evaluator.lia.org/od.php

The calculator allows users to enter laser parameters and calculate an OD based on the applicable exposure conditions.

The calculator should be used as part of a proper laser hazard evaluation—not as a substitute for the judgment of an LSO or qualified laser safety professional.

Start by confirming that the eyewear:

Do not assume that all CO₂ lasers operate at exactly 10,600 nm, and do not assume that eyewear marketed for CO₂ lasers automatically covers your particular system.

Check the laser specification and compare it directly with the eyewear's rated wavelength range.

Many CO₂ lasers operate at approximately 10,600 nm, but the first step should always be to verify the actual wavelength of your laser.

Once the wavelength is known, the eyewear must provide:

Correct wavelength protection + adequate optical density

The laser's wattage is an important input into the hazard evaluation, but wattage alone cannot determine the appropriate laser safety eyewear.

Always verify the laser wavelength and consult your Laser Safety Officer or another qualified laser safety professional to determine the required OD and PPE for your specific laser system and application.

Laser Safety Industries offers CO₂ laser safety eyewear with:

OD 6+ @ 10,000–11,000 nm. See here.

This protection range includes 10,600 nm and may be appropriate for many common CO₂ laser applications when OD 6+ provides sufficient protection for the specific exposure conditions.

Before selecting this eyewear, verify that your laser's actual operating wavelength falls within the 10,000–11,000 nm protection range and that OD 6+ meets or exceeds the optical density required by your laser hazard evaluation.