What not to laser cut

Six rules before you cut anything

1. Know exactly what it is. If you cannot identify the material, do not cut it. Check the safety data sheet (SDS) for what it releases when heated.
2. No halogens. Avoid anything containing chlorine, fluorine, bromine or iodine. Materials labelled “flame-retardant” often contain bromine.
3. The laser type does not make a bad material safe. We found no source saying a diode laser releases different gases. xTool’s diode-laser safety guide bans PVC just as CO2 shops do.
4. Do not rely on a material library alone. Stanford’s safety office notes that maker material libraries may not leave out flammable materials or give thickness limits.
5. Ventilate. Never run a laser without its exhaust or filtration working. Safety offices prefer a dedicated exhaust to the outside, with filtration as a supplement.
6. Stay with the machine. Keep a fire extinguisher nearby and never leave a running laser unattended. Paper, foam and resinous woods catch fire easily.

Why PVC is the worst offender

PVC and vinyl turn up in places you might not expect: faux leather, vinyl stickers, some “acrylic-looking” sheets and Kydex. When lasered they release chlorine-based gases such as hydrogen chloride. Epilog warns that this can do irreversible damage to the machine, and the NSF-funded MatEdU guide notes that the acid can corrode the optics and metal parts even with ventilation running. Because the danger comes from the material, the ban applies to every type of laser.

FAQ

Can you laser cut PVC?

No. PVC and vinyl release chlorine-based gases such as hydrogen chloride (HCl) when lasered. The gas is harmful to breathe and corrodes the laser’s optics and metal parts. PVC is on essentially every university and laser-maker do-not-cut list.

Is it safe to cut PVC with a diode laser?

No. The problem is the gas the material releases, not the type of laser. xTool’s own safety guide for its D1 diode laser bans PVC and vinyl, and makerspace rules for diode machines do the same.

Can you laser cut MDF and plywood safely?

They are widely cut, with care. The glues in MDF and plywood can release formaldehyde, and some glues are not suited to lasers at all. Use laser-grade sheet, run proper ventilation, and check your workshop’s rules — some universities ban formaldehyde-based MDF.

How do I know if a material is safe to laser?

Find out exactly what it is made of. If you cannot, do not cut it. Check the material’s safety data sheet (SDS) for what it gives off when heated, avoid anything containing chlorine, fluorine, bromine or iodine, and be wary of materials labelled flame-retardant.

Sources

Several of these lists borrow from each other, so the number of sources is not the number of independent tests.

• Stanford EH&S, Laser Cutters Safety Guidance (Rev. 9/26/24, archived copy)
• Carnegie Mellon EHS, Laser Cutter Safety Guideline (Rev. 11)
• University of Florida EH&S, Laser Cutter Materials
• MIT EHS, Laser Cutter Safety
• University of Washington EH&S, Laser Cutter Safety
• Penn EHRS, Laser Cutting Fact Sheet
• MatEdU (NSF-funded), Materials for Laser Cutter Machines
• Emory TechLab, Prohibited Laser Cutter Materials
• UT Austin School of Architecture, Prohibited Laser Cutter Materials
• University of Maryland Terrapin Works, Material Safety
• ATX Hackerspace, Laser Cutter Materials (archived copy)
• Dallas Makerspace, Laser Cutter Materials (archived copy)
• Bristol Hackspace, xTool S1 rules (diode laser)
• Epilog Laser FAQ, unsafe materials
• Trotec FAQ, unsuitable materials for laser processing
• Glowforge Support, Non-Proofgrade Materials FAQ
• xTool, Safety Guide for xTool D1 (diode laser)

This page is a summary for hobby and small-shop users, not a complete hazard assessment. Follow your laser maker’s instructions and your workshop’s rules, and check the SDS of any material you are unsure about.

Last checked 2026-10-27 · See also the laser power & speed converter