If you use a laser, ours or anyone else's, please go back right now and re-read the safety instructions. Accidents like this should never happen. My heart breaks for those affected by this.
It would be appropriate to put a CO detector in your units before somebody does that with one of yours. That definitely needs to be in the "filtered" units that are supposed to operate with no ventilation.
The other unambiguously suggests the example is the culprit. And as other posts in other threads suggest, the printer, whichever brand, being the source of the CO poisoning isn't even certain.
I don't work for Glowforge, and you may note my other comment in this thread, which could be taken as critical, so I'm not biased or trying to spin "damage control". And yet, I too think the thread's root's language could be more precise.
Personally I hope the cause wasn't a laser cutter, this could really hurt a young and fragile and mostly innocious industry :(
Yes, CO is similar to air's molar mass (it's actually slightly lower), meaning it will diffuse evenly through the vertical space in the room. The concentrations at the ceiling will be the same as the concentrations on the floor.
Stop spreading misinformation.
Diffusion of gasses in the air is an extremely rapid process. In a minute the concentration would be the same throughout the room.
"Should the placement of carbon monoxide (CO) detectors be influenced by CO's weight relative to air?"
http://neilhampson.com/uploads/3/4/0/6/3406995/2011co_weight....
Their conclusion agrees with you completely:
What does this say about the placement of residential CO monitors? It would be reasonable to place them anywhere in the room and expect them to be effective. Every scenario imaginable in a home would only speed the mixing of the gas within a real room, as compared to a sealed chamber — people walking, forced air flowing from vents, CO entrainment with warm air being released into a room at floor level and then rising.
The belief held by many that CO sinks is clearly wrong. Statements such as ‘‘Carbon monoxide is heavier than air, and will pool in lower areas’’ need to be refuted with facts (5). Even if CO were significantly heavier or lighter than air, it would still distribute equally from ceiling to floor.
On the other hand, they did find that the rate of diffusion can be much slower than "in a minute":
The time required for the equilibration of CO concentration was different depending on the level of infusion. It occurred most rapidly when CO was introduced in the middle of the chamber (2 min), at an intermediate rate when introduced at the bottom (40 min), and most slowly when introduced at the top (105 min). Nonetheless, the ultimate concentration was equal throughout the chamber, with no suggestion of any pooling on the floor, layering in the middle, or floating on top.
That said I watched the video for this product and I'm really looking forward to when these are widespread. It's a very exciting industry. I'd definitely buy one of these when it gets to around $1k.
They weren't students. Roger was a game developer while Valerie was a post-doc. They just happened to live in Berkeley.
How about:
Glowforge Pro + Air Filter: $5,995.00
Glowforge Basic + Air Filter: $3,745.00
Glowforge Basic: $2,995.00 Warning: You may die when using Glowforge inside without Air filter (link). You may also die when cuting these materials (link) inside even with air filter.
The results are really bad anyways, it melts and burns. I'm curious though, can you get good cutting of polycarbonate using an inert gas shield? That would be interesting.
[1] http://www.cnczone.com/forums/general-laser-engraving-cuttin...
Berkeley has been unusually cold/rainy this last week and I'm guessing they sealed up their apt and didn't realize how dangerous that was.
There are lots of things you don't want to cut on a laser cutter unless you're cutting under an inert gas, or at least nitrogen. Polycarbonate, any of the chlorinated plastics (PVC, some synthetic leather), styrenes, and polyethylene, for example. ABS melts, and Fiberglas's glass component won't cut. Acrylics cut very well. Delrin cuts OK. Wood and cloth are OK. Techshop is careful to teach people about this.
TechShop's laser cutters have compressed air coming in, a big exhaust hose going out, and a fire extinguisher nearby. TechShop has an ad slogan, "Don't try this at home. Do it at TechShop". There's something to be said for that when you're using industrial-strength tools.
In addition to the two people, their two cats died. Operating these things in a closed room is a really bad idea.