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Comment by stcredzero | Hacker News Reader

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. What's worse: a lot of cheap CO detectors are pretty shoddy.

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To add to this, here's a really interesting story of someone who thought that his landlord was stalking him, but really he slowly become poisoned by a carbon monoxide leak.

https://www.reddit.com/r/bestof/comments/34novp/user_thinks_...

He was leaving himself notes which he later didn't recognize, he thought someone was in the apartment! It was suggestions on reddit tnat made him realize it was CO poisoning.

Already knew that story, still crazy.

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 the Radon detector is the most expensive at around $250 CAD, and least critical for the short term (but for the long term concerns, anyone with a below grade section of their home should have one!).

A decent Co + smoke detector (You can often get them in one unit) should cost you no more than $30-40 CAD. Testing a CO detector isn't super easy (not like smoke detectors - just make some well done toast), but I'm trusting that if i have several different kinds well distributed throughout the house at least one of them should save us.

I focused on keeping detectors both near and & inside bedrooms, as well as having a minimum of 1 smoke + CO detector on the other floors in open spaces.

Unrelated to these gasses, I also purchased VOC sensors. These are SUPER interesting. It's amazing how the VOC level rises after a few days, and all it takes is opening a window for a few hours to bring it back to lower levels. We were renovating recently and found that after virtually every contractor the house needed hours of windows open to bring the VOC level back down to something that the sensor considered "good quality" (lower than 450 ppm).

Hope that random rant was interesting to someone :)

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...otherwise it would rise above OSHA approved levels.

In the USA, there's no regulated levels for residence..but there is for office. Funny, isn't it.

Eve Elgato: https://www.elgato.com/en/eve/eve-room

Sadly they do not break it down by substance type (which the website almost suggests it does), but i find it very interesting to monitor and that the measurements are highly correlated with painting or opening a window.

Dang! Eve looks good, especially for the price.

I have Foobot (https://foobot.io/) and looks like it cost twiec as much as eve but probably does the same thing. Though, it doesn't say if eve uses wifi..I just see it say bluetooth. I like how Eve is battery powered, you can bring it wherver you want - whereas Foobot is plugged in.

I have UNI-T UT-338C for on the fly readings. I like how the UNI-T can be portable, or plugged in and has a display. I get similar readings between the UNI-T and Footbot so I can somewhat trust it...

It's really rather decent, but I grow to hate the HomeKit protocol more every day (slow, buggy and not something I can mess around with) probably a wise move not going with something apple powered.

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

> VOC

Volatile organic compounds (VOCs) are organic chemicals that have a high vapor pressure at ordinary room temperature.

https://en.wikipedia.org/wiki/Volatile_organic_compound

Oh jesus. I'm currently renovating 2 bathrooms at once and ceramic dust is coating pretty much everything else not secured. I didn't even know about VOC's until now. I may have to invest in a detector

EDIT: I ended up ordering a Foobot after doing some homework

Oh I feel your pain. We renovated our basement and did a polished concrete floor. Brutal dust, it's just everywhere and I've tried to clean so many times but a few days later I look under something and BOOM missed a spot, it got everywhere! Masonary dust is a special kind of horrible.

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).

I have a fascination with CO poisoning for some reason or at least the chemistry behind it. CO has more than 200 times the affinity for hemoglobin than oxygen does.

You can't just go outside to get fresh air since the CO just won't let go.

I believe the normal way it works is oxygen and carbon dioxide use different sections of hemoglobin molecule so they never interfere with the way each are transported. But CO hogs it all oxygen has no chance of affixing to hemoglobin since there is nowhere to stick.

> But CO hogs it all oxygen has no chance of affixing to hemoglobin since there is nowhere to stick.

CO's action is not purely competitive. Its binding at one binding site influences the three other sites to bind oxygen so strongly that oxygen won't dissociate from the complex where it is needed; In tissues, starving them of oxygen.

> You can't just go outside to get fresh air since the CO just won't let go.

Yes you can...

http://www.remsaeducation.com/news/carbon-monoxide-poisoning...

Emphasis on "just". Yes, obviously getting fresh air is an important step when you suffer from CO poisoning but it's not sufficient. Even the site you linked to mentions you should get additional treatment.

Intuitively most people would think that just stopping to breathe CO is sufficient and breathing fresh air would displace it as quickly as with other common gasses (i.e. you may cough for a bit but recover in minutes) but the point is that CO is clingy.

EDIT: Elsewhere you agree with the assessment that the half-life under "fresh air" is somewhere around 4 hours, so I think you would agree that "just breathe fresh air for a bit" (implying minutes, maybe an hour) isn't a satisfactory treatment in serious cases.

3-4 hours is "a bit" when compared to the multiple weeks the GP suggested...

You should absolutely seek medical treatment if you suspect you have been exposed to CO. I'm not trying to make light of that. My point is simply that CO is not actually as "clingy" as some in this thread are making it out to be.

I am a paramedic. We carry a portable CO meter on our "BLS bag" (the bag that gets brought in on the vast majority of calls), because more than once a "general illness" call has turned out to be CO poisoning.

>We carry a portable CO meter on our "BLS bag" //

Do you carry other equipment for personal protection like that (or the long version - what's in the bag!?)?

"Standard" PPE (personal protective equipment) is basically our standard uniform[1], plus nitrile gloves and a radio. Additional levels of PPE include safety glasses, gowns[2], and full face shields. We also carry ballistic vests in the event a potentially violent scene.

We are a combination fire/EMS agency, so I am also a firefighter, with all the gear that goes along with that.

As far as the bags go, we have three main bags:

-The "BLS" or "Airway" bag, which contains a lot of "basic" equipment (bandages, oxygen, some common meds, etc), as well as more advanced airway management equipment (laryngoscopes and endotracheal intubation tubes, etc).

-The "ALS" or "Med" bag, which contains all ~30 medications we carry, as well as IV fluids and all the necessary pointy things to get medications into people.

-The "Pediatric" or "Peds" bag, which contains most of the same stuff as the other two bags, just in smaller quantities, and sized for kids.

There are also a few other more specialized bags (the burn bag, the trauma bag, etc), and portable equipment (portable heart monitor[3], suction[4], etc)

[1]: Stock photo of a standard "class b" uniform: https://www.lansinguniform.com/wp-content/uploads/2014/05/Fi...

[2]: https://www.spservices.co.uk/images/products/pics/1407156050...

[3]: http://www.physio-control.com/ProductDetails.aspx?id=2147484...

[4]: https://www.boundtree.com/s-scort-iii-suction-unit-596400-ph...

"After the patient has been removed to a safe area, it is important to immediately begin administration of high concentration oxygen to maximize hemoglobin oxygen saturation. Treatment and monitoring of the patient with CO exposure should continue on scene and en route to the hospital. Continuously monitor SpO2 and SpCO levels, obtain a 12-lead EKG and monitor the ECG en route. Remember that SpO2 monitoring alone is unreliable as you may get a falsely normal reading in the presence of carbon monoxide poisoning."

As with all poisons, that depends on the dose... For a low level exposure, fresh air is truly all that's needed.

I'm not trying to suggest that more advanced treatment is never necessary (I am the person who provides that treatment...), my point is simply that there are _many_ people who experience low level, chronic exposures to carbon monoxide that require no further treatment than leaving the environment.

Thanks for saying that, I had no idea CO stays in the body so long. I thought you could just breath fresh air and clear it form your system quickly.

You're correct. Breathing "fresh" air will drop the CO levels in your blood by half every few hours.

A few hours is a lot slower than I'd imagined.

If this was indeed a LASER cutter then you would definitely be able to smell all the other gases emitted with the CO. I've got a small LASER cutter and even with the hose going outside the smell very strong.

One post up above says some of the newer cutters targeted at consumers have carbon filters and exhaust the air directly back into the room. The carbon doesn't capture CO but may capture the odors from other compounds.

So, a bad design that sells well, but hides the important signal.

In case of natural gas, we have long long time ago started mandating odorization (after a lot of silent deaths): https://en.wikipedia.org/wiki/Odorizer

This time, we basically allow laser cutter manufacturers to ignore these lessons (learned with a losses of thousands of lives).

Well we don't know for sure that that was the cause yet.

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.

What CO detectors would you recommend?

The consumer ones work fine. They've come a LONG way in recent years.

They may not be accurate but they don't need to be at the levels where CO becomes fatal. It is better to have several inexpensive ones than just one or two $300 highly accurate ones. Since you don't know where the CO will be localised.

You can test them yourself fairly inexpensively look for "HOME SAFEGUARD HO-CO2 Carbon Monoxide Detector Tester, Aerosol." Get a Ziploc bag or similar air tight baggy. Place the alarm in a bag, spray the Aerosol in it, and wait. It should go off in 2-5 minutes. Obviously it is best to do this test outside.

Consumer Reports also tests them:

http://www.consumerreports.org/products/carbon-monoxide-alar...

Omega is one company I would trust for this myself; they sell for industrial applications, not homes, and have a good reputation when it comes to sensors. A CO monitor will set you back $235.

http://www.omega.com/pptst/AQM-103.html

Is there any way to know that an expensive CO detector like this is worth getting for home use, instead of one costing 10x less?

Hard to say, but Omega definitely care enough about their brand and reputation to have a good QA system and testing of products in place. Since testing that a CO monitor is working is very hard for a consumer, you rely a lot on trust in the brand.

If you can get a good, trusted brand for home CO monitors, I'd say go for it.

Apparently, Kidde is a trusted brand in fire alarms etc. in the US, so I think this one ($20) is probably equally trustworthy:

https://www.amazon.com/Kidde-Battery-Operated-Carbon-Monoxid...

Anecdotal: I've bought cheap versions of things online enough times that I don't want to do it again (just got home from helping a friend install a battery that didn't even fit properly). I've had a few things melt and a couple explode..

I shudder to think that you would risk your life on a device of questionable quality.

>I shudder to think that you would risk your life on a device of questionable quality. //

The problem is surely knowing whether the expensive equivalent is just the same internals in a different retail pack (with other 'quality' signalling). That's genuinely hard for something that needs a lab to be tested.

A CO "monitor" is permitted to alert at low levels of CO (10-20 ppm). A UL-listed code compliant CO alarm may not. I personally think this is silly.

There are a few companies that sell low level CO monitors for residential use. They're all somewhat pricey.

  A CO monitor will set you back $235.

$235 sounds (relatively) expensive. I recently replaced the 3 CO alarms in my flat - they cost me around £23 (29 USD) each [1].

[1] http://www.toolstation.com/shop/Electrical/d190/Carbon+Monox...

Are there any that work in temperatures below freezing? I'm living in my car and using a propane heater when it gets cold.

Wow. That is definitely a recipe for carbon monoxide poisoning. I encourage you to find some other way to survive, because it's unlikely you'll survive long doing that.

If you're able to get a small ceramic heater, you'll find that there are many unexpected places to plug it in. E.g. near gas station car wash exits, some parking lot lamp posts, etc. Check with the owner for permission, there are some that will grant it, especially if you're able to offer some lot cleanup or other bartered assistance for them.

Don't use a propane heater, please. It's dangerous to you and potentially to others nearby.

Source: Been there.

Any off the shelf product should be fine (there are standards they have to meet). Kiddie and First Alert are both well regarded brands.

I use First Alert personally (they have model with Z-Wave integration that ties into my home automation system). We carry a few Kiddie smoke/CO detectors on the fire truck to install if we notice a home doesn't have one (or if the one they had failed).

In regards to the smoke detectors, I love that your department does that! I think what finally drove me to realize how important working smoke detectors are, is that video of a modern room flashing over in like 3 minutes.

For those who haven't seen it, here:

https://www.youtube.com/watch?v=aDNPhq5ggoE

Surprisingly those standards won't allow low levels to be displayed, so that emergency centers don't get too many non-emergency calls.

At his point, I would just pony up some cash. Maybe bug a chemistry geek YouTuber.

I've researched this some months ago, but it isn't a one time cost. I arrived at this model:

https://www.draeger.com/en_aunz/Applications/Products/Mobile...

But if you want to do it right, you also need a calibration station and calibration gas bottles. It is quite an effort.

[No product placement, also look for Honeywell and others.]

I think CO doesn't get unstuck from hemoglobin at all. 2 weeks sounds about right, in that that would be the body's mean replacement time for a hemoglobin molecule.

The normal half-life of carboxyhemoglobin, when the patient is breathing room air, is 240 to 360 minutes (4-6 hours). The half-life of COHb can be decreased to 80 minutes with the administration of 100% oxygen.

It can be brought down even faster with hyperbaric oxygen therapy. Hyperbaric chambers are reasonably common, due to usage in both (SCUBA) diving related medicine and various therapies for wound care.

http://www.hopkinsmedicine.org/healthlibrary/conditions/non-...

>It can be brought down even faster with hyperbaric oxygen therapy.

What's the limit on that? The link you posted says 2.5 atm of pure oxygen but how does that not cause oxygen toxicity?

According to the toxicity curve from wikipedia, even at 2.5 bar, you wouldn't start to see issues until ~4 hours have past. That's enough time to remove quite a bit of CO.

https://en.wikipedia.org/wiki/Oxygen_toxicity#/media/File:Pu...

Is there a cheap and high quality CO detector? I think it's time I replaced mine since it's probably way past due.

an addition here - there are two classifications of CO poisoning: acute and chronic. Acute is deadly in anywhere between minutes and hours. Chronic ranges from not deadly to lethal and can be after hours, days, or months of exposure.

>> About 2 weeks, IIRC.

Does the CO actually get out or do the red blood cells die and get replaced?

It lets go on its own. The levels in your blood fall by half every few hours.

5.3 hours.

It's nowhere near that precise a number...

No it's within hours. A simple google search will show you that.

He indicates that the CO poisoning could have been gradual. This is not mutually exclusive with faster poisoning.

Not the point. OP (it could be a woman) said that it takes weeks to unbind when in fact the half life is 74 mins.

Leaving the house for a few hours a day would be sufficient to "reset" the COHb levels in the blood.

I'm seeing numbers like 320 minutes, 5.3 hours. Of course that's only enough halve it, not clear it completely. Leaving the house for "a few hours a day" sounds like dangerous advice to me.

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