Hit With Muriatic Acid Fumes


Active member
May 21, 2007
I was preparing to add some muriatic acid to the pool, and I was measuring and adding the muriatic acid into a bucket of water to be poured into the pool. I noticed a cloud of vapor rise up and out of the bottle of acid when I opened it, but the mist was not up near me. However, when I went to breathe, I hit a wall of vapor. :shock: I did not inhale much, and I did not inhale deeply, but yuck! I immediately stepped away into fresh air.

I was completely fine at first. About 10 to 15 minutes later, my tongue felt a bit swollen, and my throat was a bit sore. I can tell my asthma is now aggravated as well.

Am I gonna die? :shock:

I admit this scares me a bit. I did not breathe much of it, but I don't think I could have if I wanted too; it was so strong.

Anyone else experience this? Should I be wearing a gas mask to work with this stuff?

I do not like muriatic acid at all. I really wish I did not have to use it, but our pH and TA are soooo high.


Well-known member
May 23, 2007
An interesting note about Muriatic acid, I have an HBSc. in chemistry, and even in our advanced labs, we rarely were allowed to deal with the stuff because of the danger. If we did use it, it was with safety goggles, lab coats, inside a fume hood, and near all sorts of safety equipment. So I find it quite strange to imagine pool owners in shorts and sandles storing jugs of the stuff next to oxidizers (cal-hypo) in their shed, pulling it out and sloshing it around in buckets.

You need to be VERY careful with it, it will react with just about anything, including water vapour in the air, which is probably what happened to you. I'd wear thick polypropylene gloves, long pants, and long sleeves when dealing with it. If you spill any on you, you need to dilute it as fast as possible, to the point of jumping in the pool and stripping off your clothes.

Now that the scary bit is over, the damage done by any fumes will be sudden, not chronic. You've likely seen the worst of it. To be safe I would still see someone with more medical knowledge like a Doctor! And remember, you probably just felt the effects of maybe 0.1 ml of acid, imagine what a gallon can do.


TFP Expert
LifeTime Supporter
May 3, 2007
Pleasanton, CA
I mark the side of the gallon jug for quart size increments and pour directly into the pool. I think the more you mess with the stuff the more bad things that can happen.

I get the jug very low into the water with the spout only an inch or two above the water line and pour very slowly. Of course making sure there is no backflow into the jug. I found that this method reduces the fumes and spash outs. The higher you pour it above the water line the more likely it is to end up on your shorts and the more likely you are to create a cloud.


Mod Squad
TFP Expert
Platinum Supporter
LifeTime Supporter
In The Industry
Apr 1, 2007
Sebring, Florida
I apply muriatic in the pool exactly like Mas985. I am usually dressed in work clothes, but have done it barefoot in swimming trunks....I have NOT done it when I'm in a rush or have had something to drink. I take, for me, reasonable precautions.

In five years, I have never burned any clothes or skin. I also use it commonly to clean calcium deposits off plumbing fixtures in the house which requires more precaution. I've gotten a whiff of it indoors and it is, indeed, most unpleasant. To this point, I have neither grown any extra appendages nor lost any of those I currently own.

If handling acid sensibly is beyond your comfort level, you probably should not do it. IMHO, driving a car is far riskier.


LifeTime Supporter
Jun 7, 2007
Raceland, Kentucky
The good thing about muriatic acid is that you definitely know when you get a whiff of it, and your body reflexively responds to protect you. Although it is a dangerous chemical, unless you are trapped in a confined space with the fumes it would be difficult to make yourself breathe enough of it to cause serious injury. Unlike some other acid fumes, like nitric, which you can breathe without noticing until your lungs are literally destroyed. Of course that doesn't mean you shouldn't be careful with it.


The fumes from muriatic acid (hydrochloric acid) are hydrogen chlorde. When they hit water they form hydorchloric acid again! I keep the jug at arms distance and downwind when I work with it. I wear gloves and have the garden hose handy in case of spills.


Active member
Jun 13, 2007
Palm Bay,Florida
I always add my acid in the afternoon. so the wind is blowing some, as I found out the hard way doing it in a morning with no wind is a bad idea as the fumes will get you bad because the fumes surround you and By time you fig it out you will be moving to find some clean air to breath.


New member
May 23, 2007
Shoot, uncle sam used to give us muriatic acid in the military to mop the floors in the bathrooms. Makes the tile and grout shine like new! No wonder military guys die young!


Well-known member
Apr 30, 2007
Sorry but you will definitely die - its just a matter of when. You could develop chemical phnemonia, but probably not. Go to a doctor if it gets worse, but its probably just an irritation.


Active member
May 19, 2007
The first time I used the stuff I just poured it on in .. ugh, that was unpleasant, I had a headache the rest of the night. I'm in the Air Force and they're kind enough to issue me a gas mask and chemical gloves, which I now wear when dealing with the stuff. Problem solved!

The neighbors do give ma a funny look when I'm doing it though.


Well-known member
Mar 29, 2007
Southwestern Ontario
I am like most, I make sure the wind is going the right way for sure, and hold my breath if I sense any smell of it. I pour mine into a measuring cup that I place on a cafeteria tray. This way if there is a small spill it doesn't bubble up my decking, plus I can just shove the whole thing into the pool if something worse does happen. Seems to work great.

I don't usually wear much in the way of PPE, but, I should since I used to deal with a lot of nasty chemicals at work and know how quickly something can happen. I am always cautious though.


TFP Expert
LifeTime Supporter
Mar 29, 2007
Coastalish 'down easter'
Hey all!

Back in 88 when I was very new to pool work, we had the acid in 5 gal carbouys because we acid washed ~ 70 pools each spring. There were 2 stacks of the empties, 1 that had been rinsed and one for those waiting to be rinsed - I couldn't remember which pile was which one morning, as I was trying to put 2 used carbouys in the right pile, so I uncapped one of the top jugs on one of the piles - didn't see any cloud come out so figgured it was rinsed but just to be sure I took a whiff... it wasn't rinsed and I came very close to vomiting and passing out :oops: .

Another fun with acid story - When I was running the service dept we got an emergency acid wash order (the people had completely drained the pool - they were supposed to only drain 1/2 and we'd do the rest the next day and do the wash, but they forgot to turn off the pump and were in a high water area, so it had to be done that evening so they could refill before the pool floated). Unfortunately, I had given my rubber boots to the construction guys who were pouring a concrete floor and didn't remember that crucial peice of info until we drove ~ 1 hr to the job. Not having enough daylight left to go back for them, I acid washed the pool barefoot! :party: (I'm sure anyone from OSHA is having kittens at this point :wink: ) I just had my partener keep the garden hose 'at the ready' to rinse my feet when I started feeling that 'tingle' - it wasn't too bad (& my athlete's foot has never come back since :lol: )
I'm not saying that it's not nasty stuff, but IMO if you take the precautions the other posters mentioned - it's not all that evil. However, Rob makes a VERY!! good point about keeping it well away from oxidisers (chlorine) it's a bomb just waiting to go off! When I started at the pool co in NH one of the first things I did on my first day was move the acid in the store from being NEXT TO the chlorine, I put the pH+ and bi-carb between them (to act as a buffer :angel: just in case...) I was brand new and didn't even ask if I should or could - I just did it - when the boss asked me what the Heck I was doing, I explained to him the potential problem and 'POOF', I had 4 guys helping me :-D


Well-known member
May 30, 2007
Hampton Roads/Virginia
Okay, I'm new to BBB so haven't used the muriatic acid yet!! :shock: So now I don't want to mess with it. Ugh.
What else can I use in place of it?? This is to decrease PH right??? I have some of that from the pool store and have used a bit of it with no issues when I first started the pool several weeks ago . Can I just keep using the pool store's ph decreaser?? Is it safer to be around...I don't think I'm interested in the muriatic acid. :? :? :?


You can use sodium bisulfate (pH reducer or dry acid) but it is much more expensive than muriatic acid and it also adds sulfates to the water. Sulfates in high concentration can cause damage to plaster pools. If you have a SWG I would highly recommend using muriatic. It's really not that bad and no more dangerous than many things you have around your household already. Just use commom sense around it. (BTW, dry acid basically forms sulfuric acid when dissolved in water!)


Active member
May 21, 2007
I'm not dead yet! :party: The pool's pH is also in balance. 8)

One question, though. How far away from the chlorine should the MA be stored? :shock: Our shed is pretty small. :roll:

Heh. I had on goggles but no gloves. I figured I would hop in the pool if anything bad happened. I just did not expect the fumes! It really was like hitting a wall. :?


TFP Expert
LifeTime Supporter
Apr 8, 2007
Waaay NW MN
I am using the dry acid right now. My teenagers sometimes mess around too much in areas where things are stored and a broken, damaged or leaking bottle is a risk. Dry is also a risk but less with my heathens. I have seen too many chemical accidents at work from spashback and fumes. I am so covered with PPE when I put chems in the pool I look like I am auditioning for a space movie.

The stuff costs more but I so rarely have to use it I'm not concerned with price - I am lucky that my PH usually hangs on the low side.