Thermal Risk

RflkTor

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I've heard and read that acid-lead batteries can cause a release of a very very dangerous gas, H2S.
Recently got an UPS for my PC, not that demanding so the thing isn't that big you know, it's 1200VA/720W but I then realized my environment might not be ideal for it, usually 70 to 100 F/20 to 35 C in ambient temperature and kinda dusty.
Use it? Use a surge protector instead, H2S risk is my main concern.
 
I've heard and read that acid-lead batteries can cause a release of a very very dangerous gas, H2S.
Recently got an UPS for my PC, not that demanding so the thing isn't that big you know, it's 1200VA/720W but I then realized my environment might not be ideal for it, usually 70 to 100 F/20 to 35 C in ambient temperature and kinda dusty.
Use it? Use a surge protector instead, H2S risk is my main concern.
You should be fine. I use a 1500VA USP in damn near every room of my home and have never had an issue.
 
The risk is lead-acid batteries releasing Hydrogen gas, usually when charged.

It's a non-issue in a normal-sized room that isn't sealed shut.
You'd need a significant concentration, like 4% in air, to get it to blow up. No worries, OP!
 
I've never smelled H2S from any of my UPS's. I suppose it's possible. The good news is that you'll smell it long before the concentration becomes dangerous. You can hardly ignore the rotten-egg smell, it's awful.

What you DON'T want to do is to smell rotten eggs, and then ignore it. Prolonged H2S exposure can deaden the sense of smell. If you smell the stuff, something isn't right, and you need to fix it.

As michalrz says, your real "danger", such as it is, would be hydrogen build-up. Sealed lead-acids like home UPS's use shouldn't leak H2, and if they do, it shouldn't build up unless you keep your UPS in a sealed box. (H2 gas is very light and should escape any normal room quickly.) Don't keep your UPS in a hermetically sealed box or room, and you'll be fine.
 
Unless the room starts to smell heavily of rotten eggs, everything is fine. SLA batteries are very stable and generally won't out-gas unless damaged or improperly charged/discharged.

You'll probably produce more hydrogen sulfide when you fart than the batteries will put out.
Well, what if it does start to smell what do you do then?
The risk is lead-acid batteries releasing Hydrogen gas, usually when charged.

It's a non-issue in a normal-sized room that isn't sealed shut.
You'd need a significant concentration, like 4% in air, to get it to blow up. No worries, OP!
Well, what is normal size to you? This room is actually now I think of it, quite small.

I've never smelled H2S from any of my UPS's. I suppose it's possible. The good news is that you'll smell it long before the concentration becomes dangerous. You can hardly ignore the rotten-egg smell, it's awful.

What you DON'T want to do is to smell rotten eggs, and then ignore it. Prolonged H2S exposure can deaden the sense of smell. If you smell the stuff, something isn't right, and you need to fix it.

As michalrz says, your real "danger", such as it is, would be hydrogen build-up. Sealed lead-acids like home UPS's use shouldn't leak H2, and if they do, it shouldn't build up unless you keep your UPS in a sealed box. (H2 gas is very light and should escape any normal room quickly.) Don't keep your UPS in a hermetically sealed box or room, and you'll be fine.
Again, what is a normal size? The room I keep electronics is actually quite small, 10 x 10 or 8 x 10, dont remember.
 
I believe the sheer non ideal ambient is not really coming across in my initial message, I accept that perhaps, maybe, H2S concern was overblown but certainly it has been replaced for a far more insidious and covert risk, HYDROGEN GAS!
Think of it like this, entertain the thought.

Non ideal temperature, plus dust which you know it's everywhere but still, we are talking 75 to 100F/25 to 35C, my research would so far say that after 90F/32C thermal runaway becomes a real possibility, extremely dangerous, remember H2S.
But even then, let's think of the device not failing, working as intended. Hydrogen Gas would still be released from a device expected to be on and plugged 24/7, hmm. Ok.

Sure, a normal sized room you might say, the electronic room is again either 10 x 8 or 10 x 10 but let's use 10' x 9' for the sake of our little scenario. I can easily see such a device causing Hydrogen Gas to build-up in such a tiny space. It's a matter of hours even.

So we have temperature, we have H2S, we have Hydrogen Gas, we have the possibility of an explosion on the battery again, due to heat. Like the David Lynch film, Fire walk with me is the phrase that comes to mind with such a device.
Again, what's the assessment of the situation?
 
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Like the David Lynch film, Fire walk with me
Twin Peaks Season 3 Episode 8 hints at an ability to counter the fire.
If lead-acid is BOB, the solution would be a lithium-ion battery UPS.
 
Non ideal temperature, plus dust which you know it's everywhere but still, we are talking 75 to 100F/25 to 35C, my research would so far say that after 90F/32C thermal runaway becomes a real possibility, extremely dangerous, remember H2S.
But even then, let's think of the device not failing, working as intended. Hydrogen Gas would still be released from a device expected to be on and plugged 24/7, hmm. Ok.

No, hydrogen should NOT be released. Remember, any consumer UPS will be using a sealed lead-acid battery (assuming it uses that battery type at all, which is likely). Sealed batteries don't vent unless they are dangerously over-charged, which is a very unlikely failure mode. If they do vent, it's a significant one-time event that will release a small amount of hydrogen; the H2 will at that point be the least of your concerns, as it will quickly dilute to below danger concentrations. (We'd be talking about maybe a liter or two of H2 diluted into more than 12,000 liters of air, or more if the room is larger than 8x8x7. Don't forget to do the numbers.)

In other words, it's not going to happen. If you insist on worrying about dangers from your UPS, I can't stop you. I do however advise you to turn your worrying skills to something more plausible; lightning strikes on your home, for instance.
 
Well, what if it does start to smell what do you do then?

Well, what is normal size to you? This room is actually now I think of it, quite small.


Again, what is a normal size? The room I keep electronics is actually quite small, 10 x 10 or 8 x 10, dont remember.
Place your nose right up to the battery and inhale deeply.... ;) Seriously?

Room is fine, if the battery starts smoking... get rid of it.
 
I believe the sheer non ideal ambient is not really coming across in my initial message, I accept that perhaps, maybe, H2S concern was overblown but certainly it has been replaced for a far more insidious and covert risk, HYDROGEN GAS!
Think of it like this, entertain the thought.

Non ideal temperature, plus dust which you know it's everywhere but still, we are talking 75 to 100F/25 to 35C, my research would so far say that after 90F/32C thermal runaway becomes a real possibility, extremely dangerous, remember H2S.
But even then, let's think of the device not failing, working as intended. Hydrogen Gas would still be released from a device expected to be on and plugged 24/7, hmm. Ok.

Sure, a normal sized room you might say, the electronic room is again either 10 x 8 or 10 x 10 but let's use 10' x 9' for the sake of our little scenario. I can easily see such a device causing Hydrogen Gas to build-up in such a tiny space. It's a matter of hours even.

So we have temperature, we have H2S, we have Hydrogen Gas, we have the possibility of an explosion on the battery again, due to heat. Like the David Lynch film, Fire walk with me is the phrase that comes to mind with such a device.
Again, what's the assessment of the situation?
If the concerns you have about a UPS were truly as dangerous as you think, practically none of us would be here to reply to you because we'd all be dead from UPS use.

75F-100F room temperatures are nothing and should be well within normal operating temperatures. Outside temps where I live usually hit 100+ multiple times a year and if that was a problem for lead acid batteries every single car I've ever owned would have blown up because the battery temp in a hot engine bay under load in those temps is way above the outside air temp. While car batteries are not exactly the same as UPS batteries generally, they are similar enough.

Unless you go beating on the battery in the UPS with a hammer or something you're not likely to ever run into a single problem other than needing to replace the battery eventually due to age or normal use.
 
Li-on is far more dangerous and unstable, and they are more common than lead acid these days. Lead acid batteries can become dangerous and vent gas when the plates are sulfated while being charged. The charging circuits on most systems will shut the system down in the event of a battery fault. I’d guarantee that a UPS has those protections
 
If the concerns you have about a UPS were truly as dangerous as you think, practically none of us would be here to reply to you because we'd all be dead from UPS use.

75F-100F room temperatures are nothing and should be well within normal operating temperatures. Outside temps where I live usually hit 100+ multiple times a year and if that was a problem for lead acid batteries every single car I've ever owned would have blown up because the battery temp in a hot engine bay under load in those temps is way above the outside air temp. While car batteries are not exactly the same as UPS batteries generally, they are similar enough.

Unless you go beating on the battery in the UPS with a hammer or something you're not likely to ever run into a single problem other than needing to replace the battery eventually due to age or normal use.
Ignition range on H2S though? Maybe these are VLRA, would that change things?
 
You are way too fixated on this. Let it go for your own sanity.
Yeah, I might, I'm overly cautious, sorry. Look, I might have or not have done laser/fire experiments in either this room or the next one, so I wanted to know the uhhh range on Hydrogen Gas.
 
Any battery can release harmful vapors if conditions allow. SLA are among the safest and most durable chemistries out there.
 
Lower limit of H2 flammability in air, bulk, is somewhere around 4% I believe. You'd need to release a couple hundred liters of H2 into a small (8x8) room to come anywhere close. At that point, your sealed lead-acid battery clearly isn't sealed any more, and you are in no danger because you heard the loud pop when it unsealed due to failure overpressure, plus your UPS isn't working any more, which you will have noticed because your equipment isn't getting power.

Now, if you've noticed these things and then said to yourself "gee, this is a good time to play with my lasers", you might want to re-think. Instead, open a door or window for a few tens of minutes, and THEN play with fire.
 
Yeah, I might, I'm overly cautious, sorry. Look, I might have or not have done laser/fire experiments in either this room or the next one, so I wanted to know the uhhh range on Hydrogen Gas.
4% to 74% explosion range for air/ Hydrogen mix. Coming from a Chemist who worked on PEM fuel cells for the Army this discussion is bonkers, if you are concerned get a combustible gas detector for your PC/home office. This will monitor Hydrogen Sulfide also.
 
4% to 74% explosion range for air/ Hydrogen mix. Coming from a Chemist who worked on PEM fuel cells for the Army this discussion is bonkers, if you are concerned get a combustible gas detector for your PC/home office. This will monitor Hydrogen Sulfide also.
bonkers in the way im right or in the way im not??????
 
Lower limit of H2 flammability in air, bulk, is somewhere around 4% I believe. You'd need to release a couple hundred liters of H2 into a small (8x8) room to come anywhere close. At that point, your sealed lead-acid battery clearly isn't sealed any more, and you are in no danger because you heard the loud pop when it unsealed due to failure overpressure, plus your UPS isn't working any more, which you will have noticed because your equipment isn't getting power.

Now, if you've noticed these things and then said to yourself "gee, this is a good time to play with my lasers", you might want to re-think. Instead, open a door or window for a few tens of minutes, and THEN play with fire.
But what if I don't find out? couple hundred of liters doesn't seem like a lot to me. It's tiny actually.
 
The odds of an explosion are slim and none, however I would not have open source of ignition near UPS (smoking). You always hear about car battery explosions from mechanic smoking near one. Welcome to the forums,Tor.
 
Honestly I would ask your parents if it is okay to perform your laser/fire 'experiments' in the shed or do it outside to be safer.

dimwit_s_house_is_on_fire__by_kirbystarwarrior123_dfa5wzs-fullview.jpg
 
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Say it. Answer.
Wrong bear to poke.

But what if I don't find out? couple hundred of liters doesn't seem like a lot to me. It's tiny actually.
600L is needed to get an 8x8x8 room to 4%. That's hard to get all at once from a UPS without catastrophic failure. If you're running your lasers while your equipment is off, floor is melting away and eyes are burning, you have bigger issues.

If you're so concerned that you might reach a (very) small percent of ambient hydrogen in a room you're creating fire in, the real question needs to be: What are the precautions you already have against setting everything on fire? Is your room constructed with appropriate venting equipment? Can you open the fucking window while you work? This is clearly not a lab setting.
 
Wrong bear to poke.


600L is needed to get an 8x8x8 room to 4%. That's hard to get all at once from a UPS without catastrophic failure. If you're running your lasers while your equipment is off, floor is melting away and eyes are burning, you have bigger issues.

If you're so concerned that you might reach a (very) small percent of ambient hydrogen in a room you're creating fire in, the real question needs to be: What are the precautions you already have against setting everything on fire? Is your room constructed with appropriate venting equipment? Can you open the fucking window while you work? This is clearly not a lab setting.
Hard to get, but not impossible. So you say there is a chance?

But let's assume no fire or laser at all, what changes?

And what does he mean, I've been trying to crack it, I don't know what FrgMstr is alluding to?
 
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Hard to get, but not impossible. So you say there is a chance?

But let's assume no fire or laser at all, what changes?

And what does he mean, I've been trying to crack it, I don't know what FrgMstr is alluding to?
Simple solution, don't use an UPS. This has been going on for two weeks now. With anything in life nothing is 100% and nothing is 0% so no guarantees on anything.

What is it you are wanting? You have seen a lot of answers and still aren't satisfied. If you are concerned about safety then remove the variables, take the ups out of the room or ventilate it.

I am assuming this is just in your home you are doing this and not a business (if business then bring this up to your building manager/superintendant)? If you are setting up for doing tests or experiments then you design your lab to accommodate that specifically.

Actually your room should already be ventilated if you are burning things right? That would fix all your concerns.
 
Hard to get, but not impossible. So you say there is a chance?

But let's assume no fire or laser at all, what changes?

And what does he mean, I've been trying to crack it, I don't know what FrgMstr is alluding to?
Darunion is correct, for anything, there is ALWAYS a chance. Just that for most things, that chance is very, very small, because it almost never happens. Any electronic or electrical device in your house (and the wiring) has a chance of electrocuting you, or spontaneously starting a fire because of a fault, but it is quite rare. I did a few calculations xkcd "What If?"-style, and in the event that there is actually enough hydrogen physically present in the water of a UPS battery (I don't think there is, though) to reach 600L, getting it all out to mix with the air is a challenge. Of course, if you're close enough to a source (a few inches), total saturation doesn't matter not unlike lighting a fart, but you gotta be right there with the flame when it happens, and it's still not going to be explosive.

But even to do that minimal saturation with such a small source quantity, the room has to either be reasonably air-tight (keeping gas around is hard) or you have to generate all the gas in a very short time. If you're in a situation where you are rapidly electrolyzing water from the unit, the UPS isn't going to be the method that's doing it and as we keep trying to tell you, for this to occur, much worse shit in the room is going down and this is the least of your worries.

Nothing changes if you stop whatever weird fire and laser shit you're doing. When properly designed and manufactured, defect failures causing fire are exceedingly rare, it's more often someone fucking around and exposing wiring or breaking a seal or doing really stupid stuff nearby that unintentionally causes a failure mode. Using a UPS is quite safe, stop worrying about it. I have personally explosively deconstructed a car battery. It was definitely my dumbass fuckery that got it to that point and my turning the key that triggered the detonation.

For your last question, let it go. Explore the forums, read through threads, learn, join General Mayhem and grab a hotdog. This place doesn't have a 100% serious reply saturation.
 

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I am using it now and is it normal for it to have a sugary smell? I've read it could be H2S, H2S has a sugary smell in big enough concentrations, I'll wait to see if I lose my sense of smell (which means I'd die NOW)
H2S could be here right now. H2S.
I didn't smell the rotten eggs level before but maybe I ignored it? Maybe it wasn't strong enough.
Simple solution, don't use an UPS. This has been going on for two weeks now. With anything in life nothing is 100% and nothing is 0% so no guarantees on anything.

What is it you are wanting? You have seen a lot of answers and still aren't satisfied. If you are concerned about safety then remove the variables, take the ups out of the room or ventilate it.

I am assuming this is just in your home you are doing this and not a business (if business then bring this up to your building manager/superintendant)? If you are setting up for doing tests or experiments then you design your lab to accommodate that specifically.

Actually your room should already be ventilated if you are burning things right? That would fix all your concerns.
I don't do the laser fire stuff anymore, I mean, it's ventilated, like a room usually, us, no less no more.
Darunion is correct, for anything, there is ALWAYS a chance. Just that for most things, that chance is very, very small, because it almost never happens. Any electronic or electrical device in your house (and the wiring) has a chance of electrocuting you, or spontaneously starting a fire because of a fault, but it is quite rare. I did a few calculations xkcd "What If?"-style, and in the event that there is actually enough hydrogen physically present in the water of a UPS battery (I don't think there is, though) to reach 600L, getting it all out to mix with the air is a challenge. Of course, if you're close enough to a source (a few inches), total saturation doesn't matter not unlike lighting a fart, but you gotta be right there with the flame when it happens, and it's still not going to be explosive.

But even to do that minimal saturation with such a small source quantity, the room has to either be reasonably air-tight (keeping gas around is hard) or you have to generate all the gas in a very short time. If you're in a situation where you are rapidly electrolyzing water from the unit, the UPS isn't going to be the method that's doing it and as we keep trying to tell you, for this to occur, much worse shit in the room is going down and this is the least of your worries.

Nothing changes if you stop whatever weird fire and laser shit you're doing. When properly designed and manufactured, defect failures causing fire are exceedingly rare, it's more often someone fucking around and exposing wiring or breaking a seal or doing really stupid stuff nearby that unintentionally causes a failure mode. Using a UPS is quite safe, stop worrying about it. I have personally explosively deconstructed a car battery. It was definitely my dumbass fuckery that got it to that point and my turning the key that triggered the detonation.

For your last question, let it go. Explore the forums, read through threads, learn, join General Mayhem and grab a hotdog. This place doesn't have a 100% serious reply saturation.
Thanks for the post, I don't believe it would release without clearly knowing it's gone. Thanks for your help.
 
Is this for real? Trust me, if there was any H2S around, you'd know it. It's just about impossible to miss the stink, and there's nothing in a UPS battery that can make enough of it to get anywhere near nose deadening concentrations.
 
I am using it now and is it normal for it to have a sugary smell? I've read it could be H2S, H2S has a sugary smell in big enough concentrations, I'll wait to see if I lose my sense of smell (which means I'd die NOW)
H2S could be here right now. H2S.
I didn't smell the rotten eggs level before but maybe I ignored it? Maybe it wasn't strong enough.
1. Cut back on the beans.

2. It's not H2S. New stuff of any variety tends to have some kind of leftover manufacturing smell. If H2S gets to a sweet smell, you died before posting.
 
As a retired Industrial Hygiene Manager and research director I will close out my discussion with the following comments.
1. Using your nose as a detector is a bad idea, At 100–150 ppm the olfactory nerve is paralyzed after a few inhalations and the sense of smell disappears.
2. All mercaptans (i.e. gas odorants) smell alike.
3. If you are worried get a combustible gas detector.
4. UPS will not work if battery is faulty.
5. Use of non intrinsically safe devices near flammable sources is not recommended, we investigated a welder who used his cellular phone who died in a flash explosion, source of flammable gas had no odorant added.
 
Woke up to a smell I couldn't quite recognize, I'd say it was kinda rotten egg-ish not going to lie, I ventilated the rooms, left for a while, packed up the unit, kinda feel funny though, maybe real or maybe hypochondria, but there is a smell I can tell, it's odd. I tried tracking it down but alas nothing, even removing the unit wouldn't help it's a gas. 3 hours is like a reasonable time window for it to leave BUT I don't believe the 5 hours I was knocked out, there is not enough time for it to produce that much, right? Besides, I can't smell it now, I think.
I don't know, again, kinda feel odd.

As a retired Industrial Hygiene Manager and research director I will close out my discussion with the following comments.
1. Using your nose as a detector is a bad idea, At 100–150 ppm the olfactory nerve is paralyzed after a few inhalations and the sense of smell disappears.
2. All mercaptans (i.e. gas odorants) smell alike.
3. If you are worried get a combustible gas detector.
4. UPS will not work if battery is faulty.
5. Use of non intrinsically safe devices near flammable sources is not recommended, we investigated a welder who used his cellular phone who died in a flash explosion, source of flammable gas had no odorant added.
Thanks for the advice, yeah, I should probably get a detector ASAP.
1. Cut back on the beans.

2. It's not H2S. New stuff of any variety tends to have some kind of leftover manufacturing smell. If H2S gets to a sweet smell, you died before posting.
Yeah, it was a plastic smell.
Is this for real? Trust me, if there was any H2S around, you'd know it. It's just about impossible to miss the stink, and there's nothing in a UPS battery that can make enough of it to get anywhere near nose deadening concentrations.
I believe you, I just worry I'd miss it somehow, or like right now, I could have sworn that smell was it but it's rarely felt right now, 3 hours after.
 
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