PVC is the one material on this list with a definitive answer: you do not engrave it, you do not cut it, at any power on any machine. This is not a settings question but a chemical one.
What actually happens
PVC contains chlorine. Heated by the beam, it releases hydrogen chloride, which becomes hydrochloric acid on contact with moisture — in the air, in your lungs, and in whatever remains inside your machine after it stops.
The consequences are twofold. For you: immediate irritation of the airways and eyes, with effects that do not stop when exposure does. For the machine: corrosion of rails, screws, electronics and optics, continuing long after the cut. Many ruined machines were ruined in a single session.
No domestic extraction makes this acceptable: a carbon filter does not capture gaseous hydrogen chloride.
How to recognise it
PVC hides behind many trade names: vinyl, faux leather, leatherette, tarpaulin, coated tablecloth, PVC foam (Forex, Komacel), some cutting adhesives and many decorative films.
The simplest check is a density test: PVC sinks in water, polypropylene and polyethylene float. A piece that sinks should be rejected by default.
When in doubt about an unlabelled sheet, the rule is simple: do not run it. Uncertainty is not something you test on a machine worth hundreds.
What to use instead
For adhesive film: PVC-free vinyls (polypropylene or polyester) exist and laser-cut safely — look for the manufacturer's "PVC-free" statement.
For faux leather: veg-tan leather, or a PVC-free coated textile.
For a rigid white sheet: cast acrylic or polypropylene, both laser-compatible. The result is better, and your machine will not age several years in one cut.
Every figure on LaserSettings comes with the machine, the laser source, the material and the thickness it was tested on. A setting published for a 10 W diode says nothing about a 40 W CO2, and a setting for 3 mm says nothing about 6 mm: check those four things before you copy any number.
Settings are confirmed or disputed by the members who reproduce them, so reliability comes from cross-checking rather than popularity. Photos of the result — cut edges, engraving shades, scorching — tell you more than a single number found on a forum.
Whatever the material, treat a published setting as a starting point: run a small power/speed test grid on an offcut, clean the lens, redo the focus, work with fume extraction and air assist, wear glasses rated for your wavelength and never leave the machine unattended.