Oxygen Candles: Providing Emergency Air

https://minearc.com/oxygen-candles-providing-emergency-air/

by thunderbong • 4 years ago

323 138 4 years ago

minearc.com

nielsbot• 4 years ago

Smarter Every Day did an interesting series of videos about nuclear submarines.

They use these candles to help replenish the oxygen in them: https://www.youtube.com/watch?v=g3Ud6mHdhlQ

pottertheotter• 4 years ago

I just watched that today! Super interesting set of videos. I highly recommend watching them.

rdl4• 4 years ago

Most interesting part for me was the basically continuous education aspect for everyone on board, as well as the very frequent drills. I guess a combination of keeping people educated/trained and avoiding idleness in such an environment for months at a time.

rplnt• 4 years ago

I'm kinda torn on this. On one hand it's super interesting, on the other it's state-sponsored army propaganda series, luring in young Americans, painting everyone in service as a hero.

nickelpro4• 4 years ago

As mentioned in the video, candles are a backup/supplemental form of oxygen generation. Older platforms will have an AEOG (Automated Electrolytic Oxygen Generator), popularly known as "the bomb", and newer platforms will have the substantially safer LPE (Low-Pressure Electrolyzer).

Burning candles is a hassle and creates a big mess, to the consternation of junior enlisted who have to haul clinkers around and clean up the constant dust storm they leave behind. That said, huffing that good O2 straight out the spout will keep you awake, especially if your boat has been below 18% for awhile.

imwillofficial• 4 years ago

I remember A gang telling me how explosive the whole AEOG process was when I checked in. It literally is a potential bomb.

fmakunbound• 4 years ago

At the end of the movie about the Kursk, someone drops one in water accidentally and it seems the air ignites afterwards. Are these candles the same thing?

mothsonasloth• 4 years ago

That was a potassium or alkali metal oxide that reacted with the salt water and exploded

ck2• 4 years ago

This is blowing my mind, probably envisioning the wrong size of the candle for this kind of output:

The candle supplied by MineARC Systems burns for approximately 60-90 minutes, producing 2600L of oxygen. This amount can provide approximately 20 hours of breathable air for four people. An oxygen candle cannot have its oxygen production regulated or halted and once ignited; it produces oxygen at a rate of approximately 28 Litres per minute until it is exhausted.

Oh I see now, it's that big metal cylinder on the floor, they are going to pour the powder into it and ignite?

https://minearc.com/wp-content/uploads/2021/01/cristel-train...

joosters• 4 years ago

I'm also struggling to get an idea of the size of the candle; the article gives no information and it's unclear if the photos of the demo are using the same product as described in the text. Surely something that can produce 2600L of oxygen must be pretty big? It's a shame that the page gives no clue as to the size and weight.

Another page details a 'rugged oxygen generator' - https://minearc.com/products/emergency-response-products/rug... that produces 90L of oxygen over 15 minutes, and that is 115mm x 284mm, weighing 2.3kg. Confusingly, the PDF of the product specs shows that it comes with a mask - so 90L of oxygen is for one person, for just 15 minutes here? And if used with a mask, is it actually pure oxygen being produced, or breathable air (where does the nitrogen come from?) I'd love to know more, but the website doesn't tell us.

aspectmin• 4 years ago

Average human: breathes approximately 7 liters per minute of air, give or take @ 21% oxygen. Maybe 22L of oxygen under normal respiratory demand. More if under stress of course.

At 100% oxygen that’s 105L of O2? So guesstimating almost 100% O2?

Source: am paramedic, not doctor or respiratory therapist.

arrosenberg• 4 years ago

It's not ignited, this is how airplane oxygen systems work. A phosphorus match provides the activation energy (as heat), which causes the decomposition of Sodium Chlorate (NaClO3) to Sodium Chloride (NaCl, table salt) and free oxygens. The oxygens combine to form atmospheric oxygen (O2).

nickelpro4• 4 years ago

At standard conditions, a single mole of oxygen occupies 22.4L. The conversion rate from NaClO3 to O2 is 2-to-3, so for every two moles of sodium chlorate you burn, you get three moles of Oxygen, or 67.2L.

The molar mass of NaClO3 is 106.44g.

So some quick math, to fill 2600L we need 116 moles of oxygen, which we can produce with 77 moles of sodium chlorate. Multiply by the molar mass and we get ~8kg.

Sodium chlorate has a density of 2.49 g/cm^3, so an 8kg slug will fit in a 3.2L bucket.

3L of powder gets you 2600L of oxygen, not bad!

VaxWithSex• 4 years ago

Thanks, I attempted to do the calc in my head... and it's been to long, that I learned Chemistry in school apparently.

manholio• 4 years ago

He did the math, what a legend.

waynecochran• 4 years ago

I wish they had a video demo or at least an image of one burning.

tyingq• 4 years ago

Still doesn't show the burning, but shows the setup, inserting a red phosphorous igniter, etc: https://youtu.be/h7Jonu6cXoY?t=396

peterpost2• 4 years ago

I don't know why but that was incredibly satisfying to watch as well as educational.

Maursault2• 4 years ago

from the video: > if carbon dioxide level exceeds 25ppm

The global average atmospheric carbon dioxide in 2020 was 412.5ppm. We're so screwed, aren't we?

perbu• 4 years ago

Hollywood has always perpetuated the myth that when you are in an air tight room you'll die as you run out of oxygen. The CO2 poisoning will kill you before you run out of oxygen.

So, if you're sitting in a nuclear shelter, remember to get the CO2 scrubbers working first, then worry about the low oxygen.

kolinko2• 4 years ago

Huh? How is Hollywood at fault?

I think the myth is older than Hollywood and it is ingrained in our languages - when people begin to suffocate they say „I meed more air”, not „The air is to stuffy”. And this leads to a mental model of bringing more oxygen in as helpful instead of letting co2 helpful.

jbay808• 4 years ago

Hollywood at least got it right in Apollo 13!

connordoner• 4 years ago

If memory serves, the incorrect storage of oxygen candles on Valujet Flight 592 was the cause of its crash.

kappuchino• 4 years ago

Good memory! Well, kind of ... here is the NTSB Report on the crash (PDF): https://www.ntsb.gov/investigations/AccidentReports/Reports/... - its interesting: Planes back then had an emergency oxygen system that worked on the same principles like the candles mentioned above, but these were much smaller. The crashed plane transported discarded / expired oxy generators in loose cardboard boxes since they were not labled as hazardous materials. One of theses generators was probably the cause for a chain reaction and the crash.

EdwardDiego• 4 years ago

Older Admiral Cloudberg write-up on that crash:

https://imgur.com/a/vodAg

ChuckMcM• 4 years ago

For fun, I went looking to see if you can buy one. In theory, you can buy them here: https://www.oclugo.com/our-products/chlorate-candles/)

I'm guessing the best place to find them would be a military surplus dealer.

kolinko2• 4 years ago

This website has claims falsely that oxygen tanks need co2 scrubbers and candles don’t. That is not true and can get people hurt!

You need co2 scrubbers for any oxygen producing solution, since co2 kills faster than o2 scarcity.

Having a candle, and just a candle alone in a hermetically sealed room will result in suffocation as fast as without it.

I reported the post as it contains false and dangerous info.

bryanrasmussen• 4 years ago

Is there such a thing as a portable c02 scrubber - other than a plant?

rdl4• 4 years ago

Yeah -- soda lime, etc. e.g. https://minearc.com/remove-co-co2-in-refuge-chamber-chemical...

swiftcoder• 4 years ago

And plants are not viable as CO2 scrubbers on small scales. It takes a lot of plants to scrub the CO2 exhaled by a single human - somewhere on the order of 10 full-size trees!

frederikvs2• 4 years ago

Yes, e.g. if you look at "rebreather" diving equipment, it's essentially a backpack life support system, including CO2 scrubber.

rootusrootus4• 4 years ago

Wasn't that one of the things Apollo 13 had to figure out how to rig up in order to survive?

rdl4• 4 years ago

I don't see where it claims that.

They point out that piped air is one option (which is basically continuous open circuit in these settings; exhausting to outside.). The alternative is oxygen cylinders mounted on the chamber (or inside the chamber), which (generally) require scrubbers.

Oxygen candles are then mentioned; they are essentially a nearly direct replacement for oxygen cylinders, but with somewhat better storability. It is silent on whether co2 scrubbing is needed, but obviously would in the same settings oxygen cylinders would.

SapporoChris2• 4 years ago

"A candle is an entirely independent source of oxygen from within the refuge chamber. In this way, it’s isolated from common faults found in the other sources:

Compressed Air: The feed can often be compromised during an emergency due to damage to the circuit or carbon monoxide contamination requiring the chamber to be isolated."

The candle is not isolated from the common fault of carbon monoxide contamination. Both Oxygen candles and oxygen cylinders will generally require scrubbers.

swixmix• 4 years ago

Oxygen candles smell bad. I would never want to use one except in an emergency situation. No scrubber necessary if I’m just evacuation.

xenadu02• 4 years ago

in a hermetically sealed room

I thought these chambers have pressure-triggered relief valves and rely on elevated pressure in the chamber to force air out? Basically dumping some of the existing air/gas in the chamber which carries away some CO2 with it.

FieryTransition• 4 years ago

Yeah, unless you need to stay silent for detection reasons or warfare, my guess would be that in a fixed facility, it would be way cheaper and reliable to have a positive pressure or flow of air going outward. I've seen windows and buildings do this completely passive, so a modern design would only have this as an absolute emergency, as they are dangerous and doesn't solve the Co2 problem.

Don't see how this is relevant for civil use though, but hey, maybe some paranoia can sell some candles.

bell-cot3• 4 years ago

I disagree, for contextual reasons. Oxygen candles are an emergency safety supplies item for people who get serious training in industry- and facility-specific safety procedures. Notice the slant to the headings, language, photos, etc. on the page. This is very clearly not a consumer product, and phrases such as "Used as the last means of breathable air within a refuge chamber..." really don't suggest "try this at home, kids!".

modec4• 4 years ago

But there is also an oxygen candle above every seat in passenger airplanes, right? Then it would be a consumer product ...

danuker• 4 years ago

The page doesn't technically say that candles don't require scrubbing. Candles also require scrubbing. But the disadvantage is omitted from candles, while explicitly presented for cylinders:

"Oxygen cylinders are used in the event compressed air fails and generally require the support of a scrubbing system to remove carbon dioxide [...]"

Oxygen cylinders are also used as an emergency non-consumer product. The comparison is a misleading one.

foxyv• 4 years ago

This is correct. A person in a hermetically sealed suit will die of CO2 poisoning a long time before Oxygen deprivation. However in most mines, they will engineer gas permeability so that CO2 and other poisonous gasses can seep to areas with lower concentrations and out of the mine. Coal mines seem to be particularly bad with regards to permeability.

In this case, an Oxygen candle _MAY_ be enough to keep people alive. However, why O2 tanks would need scrubbers and candles wouldn't doesn't make any sense.

https://www.hindawi.com/journals/ace/2018/3976505/

https://www.cdc.gov/niosh/mining/works/coversheet1621.html

samatman• 4 years ago

Just so we're all perfectly clear, this one poster got upset about this website and reported it for misleading information and this is now the top comment.

The company sells an air scrubber: https://minearc.com/products/air-quality-management/life-sup...

I love this place.

throwawayboise2• 4 years ago

False and dangerous to whom?

Anyone in a position to be using oxygen candles or bottled oxygen in a survival shelter setting is likely to have had safety training in how to use them, and if it is a situation where CO2 concentration is likely, that should have been accommodated in the construction of the refuge or shelter.

HWR_14• 4 years ago

You need co2 scrubbers for any oxygen producing solution, since co2 kills faster than o2 scarcity.

Given their uses are the space station, planes and submarines, cant you just vent some of the atmosphere out since you're in a pressurized tube of some kind to lower the CO2?

rtkwe• 4 years ago

It's far too expensive to launch new material up to do that. It's much better to scrub out the CO2 specifically than to throw out mixed gases. If you're just removing CO2 you only need to replace it with new oxygen which can be electrolicized from water stores but if you're tossing out cabin air in bulk there's stuff like nitrogen that's harder to replace. The ISS is basically sea level air with 21% O2 and the rest nitrogen plus trace CO2 and other gasses, that nitrogen would be much harder to replace.

With hydrolysis you just have waste Hydrogen to toss which could in the future be combined with CO2 from the scrubbers to create methane fuel (probably not in significant quantities but it closes the cycle on O2 as the Sabatier reaction also creates H2O which could feed back into electrolysis or drinking.

lgats• 4 years ago

   The candles can enter a state of elevated oxygen (maximum 32%), classified as oxygen-enriched. However, the same fire ignition risks remain at these percentages, and no additional ignition risk is present.

i do not think this is accurate, considering the candle produces pure oxygen, this risk would be highly dependent on the environment and amount of air

londons_explore• 4 years ago

It's notable that humans cannot detect low oxygen levels.

Tasks become harder and you make worse decisions, but at no point will you think "I need more oxygen, better light the candle".

On the other hand, high CO2 is pretty detectable. You'll start to find the air 'stuffy' and it will be immediately obvious there is something wrong with the air.

tialaramex2• 4 years ago

Even high CO2 - which your brain does detect - won't be detected fast enough by your brain to do anything useful about changes that arise very suddenly, because the sensor is measuring your blood, and high blood CO2 can mean you're seconds away from unconsciousness but with impaired cognition. You're screwed.

Humans will clamber down into a space that's been flooded with CO2 (to fight fires or by mistake), go, huh, that's not... er... bonk, and lose consciousness. Then others up top are likely to climb down to "save" the people who just fell over for no reason and suffer the same fate.

NickNameNick• 4 years ago

This happened on a log carrying frieghter near here, a few years ago.

The unprocessed logs in the holds are slowly rotting, so the air in the holds can be depleted of oxygen.

A crewman went into the hold to check on something, and collapsed. Another crewman went in to rescue the first, also collapsed. I don't recall how many went in, but eventually someone grabbed an oxygen tank and managed to save the last one. The rest died.

_Algernon_• 4 years ago

Are you sure those cases are CO2 and not CO? Iirc CO is the truly fucked up one because it binds to hemoglobin much more readily than CO2 thus displacing both CO2 and O2 in the blood.

rocqua2• 4 years ago

Is this because we don't feel out of breath by lack of blood oxygen, but by an excess of blood CO2? Also related to hyperventilating causing fainting because you scrub out CO2 and hence think you have plenty of oxygen, and the use of a paper-bag to re-circulate some of the CO2 to keep blood levels of CO2 high enough.

matsemann2• 4 years ago

Yes. If you try to hold your breath, the pain you feel is from CO2 buildup, not because of a lack of oxygen. If you lie still, the oxygen would last for many many minutes, but most people will be in such a pain after a minute or two that the body refuse to keep holding the breath.

Consequently, that's why hyperventilating is absolutely a no-go when freediving. It tricks your body, by not triggering the CO2 feeling. So then you can suddenly pass out without feeling you were close to running out of air.

t0mas88• 4 years ago

A dropping level of CO2 from hyper ventialtion also disturbs the acid-base balance in the blood which in itself can cause dizziness, impaired mental function and tingling fingers as if you have a lack of oxygen.

At high altitude it's easy to mistake this for hypoxia (due to loss of pressure), because the feeling and visible symptoms can be very similar.

The distinguishing symptom is seeing blue lips/fingers, that doesn't happen with hyperventilation. But if you've taken hypoxia that far you're in a lot of trouble.

Recommended approach for flight crews is to not bother figuring out whether it's hypoxia or hyperventilation but instead for everyone to put on oxygen masks, verify each other's masks and focus on breathing normally. It will fix both issues and ensures that the rest of the crew is fine in case it was hypoxia.

prima-facie• 4 years ago

I believe these are the same candles used on submarines to make oxygen: https://www.youtube.com/watch?v=g3Ud6mHdhlQ

ChrisMarshallNY• 4 years ago

I remember these critters, from the 1970s: https://en.m.wikipedia.org/wiki/SolidOx_(welding)

peter_retief• 4 years ago

They have these "candles" in submarines for emergencies, I was told on a submarine tour some years back.

Nice summary of the process.

nickpeterson• 4 years ago

I’m missing something, it says these burn at 1100 degrees. There is no oxygen but enough space for me to be ok burning something at 1100 degrees next to me?

acquacow• 4 years ago

That really depends on the density/surface area of the item. I mean, a standard light blub filament burns at like 3000F, but you don't really feel that.

lapsis_beeftech• 4 years ago

It sounds like a lot but it is about the same temperature as that of a regular wax candle flame.

Maursault2• 4 years ago

these burn at 1100 degrees

Would be cool if something else could be done with the heat to get rid of the CO2, like a Sabatier reaction (sorry, a bit handwavy).

notadev• 4 years ago

For decades the US Navy used the OBA[1], or Oxygen Breathing Apparatus, for fire-fighting, which also worked using a sodium chlorate candle. I had only ever used them in boot camp, as when I got to the fleet they were starting to switch over to SCBAs — what actual fire-fighters use on land. I was always terrified of the thought of having to use one in because I vaguely recall something about them potentially exploding if they got too wet which seemed almost guaranteed being on a ship in the ocean.

A few years ago, maybe 2015 or so, I was walking through base on my way home and saw a moored tugboat was on fire. The two guys on board were in OBAs trying to put it out while waiting for the base FD to show up, so I suppose they’re still used in some places.

[1] https://en.m.wikipedia.org/wiki/Oxygen_breathing_apparatus

swamp40• 4 years ago

Mars

bartchamdo• 4 years ago

https://www.oclugo.com/our-products/chlorate-candles/

This provides accurate info on specifications and the details about these candles/devices from a different manufacturer. Including % of particulates.

jacquesm• 4 years ago

the oxygen-producing chemical is sodium chlorate

Stupid question: How is it the sodium chlorate and not the barium peroxide that produces the oxygen?

oasisbob• 4 years ago

In 1997, a chemical oxygen generator failed aboard the Mir space station, and caused a pretty nasty fire:

https://en.m.wikipedia.org/wiki/Vika_oxygen_generator

https://www.nasa.gov/pdf/602090main_44s_international_life_s...

Oxygen Candles: Providing Emergency Air

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