It goes without saying, but we’ll say it again anyway. Wear the appropriate eyewear protection. Looking directly at a Class 4 laser beam from as far away as 500 meters is still too close to avoid temporary, or in some circumstances, permanent eye damage. Even the reflection and scattering of the beam hitting the material you are engraving can pose a hazard.

Consider buying a pair of comfortable and verified goggles instead of relying on the often no-name pair of specs provided with budget laser engravers. And for the safety of others when using a portable laser engraver, lock the room down (or cover the engraver up.)

We see plenty of slick marketing vids for portable laser engravers showing off the devices’ portability by engraving objects about the house, at the skate park, and behind the bar at a coffee shop.

It looks handy, but really, these environments should be closed off to bystanders and animals. Anyone in the eye line of the laser should be wearing goggles.

Laser engraving is a process by which you burn, even vaporize, thin layers of material from the surface of an object. And just as with materials burning conventionally, this process produces smoke, gases, other potentially nasty airborne emissions that you’re better off not breathing in.

As with any desktop laser engraver, you should be operating a portable laser engraver in a well-ventilated space. Open windows, create a draught; anything you can do to exchange the air is good for you and any living, breathing pet, friend, accomplice, colleague, enemy, or just garden variety strangers in the vicinity.

Laser engraving is a process by which the high energy of the beam precisely burns the material’s surface, vaporizing material away into the air. A thin layer of material scatters, leaving your design behind. Simple enough, but materials such as wood take to engraving much better than others, like glass.

Since you’ll be engraving in a well-ventilated space, the typical smoke that wood (and hopefully not much else, if it’s untreated) gives off is a comparatively minor irritant compared to the downright dangerous emissions from synthetic materials. Some artificial compounds emit toxic chemicals and dust at the point of engraving. That, and they simply don’t engrave well, undesirably melting or bursting into flames.

Notable among these no-go materials are:

• Polyvinyl chloride (PVC), commonly seen as synthetic “leather” or simply as vinyl. Releases chlorine gas when burned, which is deeply toxic. (Generally, any halogenated compound will react in a similarly unpleasant way.)
• Polystyrene & polypropylene foams will both flame and melt easily under a laser.
• Acrylonitrile butadiene (ABS) tends to melt rather than the desired vaporization when engraving and can give off cyanide gas, which is lethal.
• Epoxies are known to release harmful gases when broken down by powerful lasers (perhaps less relevant to portable laser engravers, but still good to know).

There are great materials lists out there giving the expected result upon contact with a laser – don’t laser anything and everything expecting it to be fine; do brush up on material chemistry and composition, and laser engrave safely.