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Carbon monoxide poisoning from 3D laser printer may have killed Berkeley couple

sanfrancisco.cbslocal.com

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Re: Carbon monoxide poisoning from 3D laser printer may have killed Berkeley couple

#211

Post by a_g »

towngas or coalgas that is piped in for cooking is hydrogen and carbon monoxide, has all the other possible sources of carbon monoxide been ruled out before nailing it on the laser cutter or 3d printer? https://en.wikipedia.org/wiki/Coal_gas

i'd prefer it that the 'authorities' do a thorough and scientific investigation and release the results in public on the internet, this needs to be proven beyond all doubts that it is caused by the laser cutter or 3d printer

if this is not done, it would stir worldwide unnecessary panic about laser cutters and/or 3d printers by saying that laser cutters and/or 3d printers produces carbon monoxide and is dangerous and hence cannot be used

i'm not sure about laser cutters but normally 3d printers is more a fire hazard than do anything else, i.e. 3d printers main hazard is fire, but carbon monoxide is likely 'fake and invalid/assumptions/speculations'

Re: Carbon monoxide poisoning from 3D laser printer may have killed Berkeley couple

#212

Post by jrickert »

allenrabinovich wrote: post #101

Hi folks. Val and Roger were dear friends, and I am on the ground here, and I'd like to respectfully ask that you refrain from speculation. The press is rushing to print sensational items, and they don't know the actual facts. I've been talking to the police directly, and nothing is conclusive yet. Nothing has actually been ruled out, nor determined to be the cause. They don't even have full toxicology reports yet, t…

I knew Roger through a meetup group and a mutual friend. I'm sad that our community has lost such a bright and talented person. He was a big inspiration and will continue to be. I'm glad to hear that people are mobilizing to keep Shard going.

Re: Carbon monoxide poisoning from 3D laser printer may have killed Berkeley couple

#213

Post by jostmey »

allenrabinovich wrote: post #101

Hi folks. Val and Roger were dear friends, and I am on the ground here, and I'd like to respectfully ask that you refrain from speculation. The press is rushing to print sensational items, and they don't know the actual facts. I've been talking to the police directly, and nothing is conclusive yet. Nothing has actually been ruled out, nor determined to be the cause. They don't even have full toxicology reports yet, t…

Could CO be produced by a clogged clothing dryer?

Re: Carbon monoxide poisoning from 3D laser printer may have killed Berkeley couple

#214

Post by nkurz »

pixelbill wrote: post #203
agumonkey wrote: post #200

Earlier quoted context omitted.

But if sources are at human head level, by the time it reaches the ceiling, you already inhaled a fair amount of CO ? what did I get wrong ?

Nope. Diffusion of gasses in the air is an extremely rapid process. In a minute the concentration would be the same throughout the room.

I found this paper that directly tested different positions of detectors:

"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.

Re: Carbon monoxide poisoning from 3D laser printer may have killed Berkeley couple

#215

Post by kneel »

Iv wrote: post #184
stcredzero wrote: post #18

CO poisoning is cumulative. It takes a long time for CO to get unstuck from hemoglobin. (About 2 weeks, IIRC.) It could have snuck up on them slowly, then one evening with the cats "napping" they felt particularly tired and thought to themselves, "We must be in hibernation mode from the chilly weather," then they went to sleep then never woke up. CO is odorless. You might get a headache, or you might only feel tired.…

If it was a progressive build up I really doubt the cats would have died the same day as the two humans. It feels like a sudden occurrence. And like the top comment said: even the CO poisoning is not confirmed yet. That smells of an easy sensationalist headline there.

Berkeley has been having it's coldest/rainiest weather of the year during the last week. Really heavy rain last weekend. Unlike most of the year where everyone can leave their windows open because the weather is almost always sunny and 70.

They may have had a deadly amount of CO/particulates from their laser cutter in their apt but their ventilation kept them alive. Closing their windows during last week's rain/cold spells could have been deadly. Also there is a possibility of particulate buildup in vents that could have been released if they turned on their heat in an enclosed apartment.

CO leaves you with diminished capability to bind o2, breathing in a small enclosed apt leads to a buildup of CO2. This tragedy could be a combination of CO and CO2 inhalation.

Re: Carbon monoxide poisoning from 3D laser printer may have killed Berkeley couple

#216

Post by sctb »

robinhouston wrote: post #23

Off topic, but I’ve never seen the care-of symbol (℅) used in place of percent (%) before. I’m really curious how that could happen. On my keyboard I can type % as shift-5, but there’s no way to type ℅ without selecting it from a list of characters.

We detached this subthread from https://news.ycombinator.com/item?id=13507997 and marked it off-topic.

Re: Carbon monoxide poisoning from 3D laser printer may have killed Berkeley couple

#217

Post by exhilaration »

fma wrote: post #159
verelo wrote: post #119

Earlier quoted context omitted.

I recently started getting very interested in air quality in my house. I decided to take a similar approach to air quality that I do with the stock market: lots of small, well distribute bets whenever possible. For context, our house is 3 levels with a furnace in the basement (cold climate; Canada) I ended up with 3 different brand of CO detectors, 2 different brands of smoke detectors and 1 radon detector. By far th…

Which VOC detector do you have? After I purchased my new house (USA, Georgia) I put in the detectors. My wife is from China where people are rightfully paranoid about formaldehyde - due to low quality building material. It's basically the same in the USA, except people are a lot less knowledgeable and informed about it. My cabinets, drywall, paint all had high level of formaldehyde. Had to always had the windows open…

Which one do you have that breaks it down by substance?

Re: Carbon monoxide poisoning from 3D laser printer may have killed Berkeley couple

#218

Post by [deleted] »

exhilaration wrote: post #217
fma wrote: post #159

Earlier quoted context omitted.

Which VOC detector do you have? After I purchased my new house (USA, Georgia) I put in the detectors. My wife is from China where people are rightfully paranoid about formaldehyde - due to low quality building material. It's basically the same in the USA, except people are a lot less knowledgeable and informed about it. My cabinets, drywall, paint all had high level of formaldehyde. Had to always had the windows open…

Which one do you have that breaks it down by substance?

[deleted]

Re: Carbon monoxide poisoning from 3D laser printer may have killed Berkeley couple

#219

Post by danieltillett »

kuschku wrote: post #204
danieltillett wrote: post #96

Earlier quoted context omitted.

The trouble with MSDS is that the lawyers have got to them and they all end saying the same thing (look at the one for salt [1]) and so people become blasé about the really dangerous risks. When I was an academic I had huge problems with students working with the truely dangerous chemicals in an unsafe manner because they couldn't tell the difference. I had to run little informal classes with my students where I woul…

> Do not ingest. > In case of Skin Contact: Wash with soap and water. Cover the irritated skin with an emollient. Get medical attention if irritation develops. Cold water may be used Okay, you’re right, these are overly alarming.

You should see the MSDS for dihydrogen oxide [1].

1. https://www.sciencelab.com/msds.php?msdsId=9927321

Re: Carbon monoxide poisoning from 3D laser printer may have killed Berkeley couple

#220

Post by i336_ »

verelo wrote: post #119
stcredzero wrote: post #18

CO poisoning is cumulative. It takes a long time for CO to get unstuck from hemoglobin. (About 2 weeks, IIRC.) It could have snuck up on them slowly, then one evening with the cats "napping" they felt particularly tired and thought to themselves, "We must be in hibernation mode from the chilly weather," then they went to sleep then never woke up. CO is odorless. You might get a headache, or you might only feel tired.…

I recently started getting very interested in air quality in my house. I decided to take a similar approach to air quality that I do with the stock market: lots of small, well distribute bets whenever possible. For context, our house is 3 levels with a furnace in the basement (cold climate; Canada) I ended up with 3 different brand of CO detectors, 2 different brands of smoke detectors and 1 radon detector. By far th…

Was very interesting to me!

I'm curious what options are out there that will connect via something like RS232 or USB and let you tie into a centralized logging system (which would be incredibly easy to build). "Windows app with one-click data export" would be nice but isn't quite the same as a realtime feed.

The main question would be whether polite pokings would produce protocol documentation, if this isn't already shoved in a forgotten corner on the website (or something).

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