Failed C02 tank. One of the most frightening things.

[hlmbrwng]

Hey folks. I haven't been on here in a couple of years. I got back on just to post about this to see if anyone else has stories about this.
I was in the kitchen brewing, and I heard the loudest hiss/white noise sound I've ever heard in my life. I had no idea what was going on. In the other room, I had a CO2 sitting there.
After the initial shock, I ran around the apartment until I realized what it was. It was the CO2 tank. Mind you, it is only about 70F and is no different than the homebrew store temperature in which it sat on a rack. I just swapped out my empty tank last week for this one.
The knob was turned all the way shut. I figured that the CO2 was being released from a small hole, which is likely part of a failsafe.
I work as an acoustical engineer...I'm going to guess that it was producing about 120-130 dB SPL. I really have no idea. But my ears still hurt. I have never heard anything this loud in my life. This happened an hour ago and I'm still shaking.
I'm also thinking about how it possibly could have been worse.

 

[Yooper]

I'm glad you're ok! I remember a couple of years ago a guy on the forum had one blow in his backseat as he was driving, and he almost suffocated but had the presence of mind to put down the windows quickly and get to the side of the road.

Very very scary.

 

[day_trippr]

Looks like the burst disk went to Heaven.
I can certainly understand the degree of alarm one might experience when that happens!

 

[SouthBounds]

Glad you are ok! Burst disks are serious. Google scuba tank failures if you want to see what happens with a little more pressure. Not for the faint of heart.

 

[matt_m]

I can only imagine. I've heard a hose blow on an plastics machine that had 2 500 gallon air tanks and a rupture disk blow on system that recovered helium from an different industrial process. Both were areas where hearing protection was recovered but damn...

 

[hlmbrwng]

Glad you are ok! Burst disks are serious. Google scuba tank failures if you want to see what happens with a little more pressure. Not for the faint of heart.

A little more pressure? Geez, I thought the pressure of these were high already. I may pass on the google search, but it does make me realize how lucky I am.

 

[bkboiler]

Yep! Glad too that it looks like it did not fall over!
Always good to secure the tank!

 

[Bobby_M]

I've seen a burst disc go on a 20LB tank. Same scary episode but lasted 4x as long. This was a tank on a delivery truck and it was a 95F day and the tank was painted a dark color and absorbed too much heat.

 

[passedpawn]

That tank is a great example of (PV/T)1=(PV/T)2.

 

[jrgtr42]

Glad to know everything is OK - sounds scary as heck!!
I would contact the CO2 supplier and let them know what happened - maybe they'll replace it.
What is the certification date on that tank? is it recent or about to expire?

 

[Jag75]

Dang that's crazy ! .....what's a burst disk?

Once those go off like that is it best just to get away from it and let it do its thing ? Especially if it's in the off position right, can it do that when it's in the open position? ....how am I gonna sleep with a 20lb tank in the next room now lol

 

[day_trippr]

It's the thing that gives up its existence if an over-pressure condition exists, instead of turning the entire cylinder into shrapnel...

Cheers!

 

[Jag75]

It's the thing that gives up its existence if an over-pressure condition exists, instead of turning the entire cylinder into shrapnel...

Cheers!

Is that little hole where the disc was ?

 

[day_trippr]

That's the vent hole, the actual burst disk (also called "rupture disk" and "frangible disk") is inside the removable collar with the vent hole.
They can be replaced, of course. Blowing a disk isn't fatal to cylinder or regulator...

Cheers!

 

[Jag75]

Thanks @day_trippr

 

[Transamguy77]

That is scary! I had one go on a paintball tank that was left in the car, 20oz was scary enough, can’t imagine 5lbs.

 

[donovanlambright]

Yikes. The little screw on the very top of my tank has gotten rusty. Last time I had it filled, they strongly advised that I replace it once the tank runs out before filling it again. It's on the outside of my keezer in the garage so I'm not super worried about it but I will definitely heed their advice.

 

[duncan.brown]

This thread got me thinking about the 35 lbs of CO2 that I have in the back of basement and the fact that my kid plays in the front part. I decided to get one of these:

Remote CO2 Storage Safety Dual Alarm

This is their older model and it’s currently reduced in price. At $400 it’s still expensive, but at least I’ll have peace of mind that a leak (or a burst disk while we are out of the house) won’t asphyxiate the family when they go down to the basement.

Here's the calculation I did. My basement is 26' by 24' by 8.5'. In SI units, it has a volume of 150m^3. Using PV = nRT, where P = 1 atm = 101,000 Pa, n = 8.31 m^3⋅Pa⋅K^-1⋅mol^-1, and T = 291 K, I get n = 6270 mol of air in my basement. Normally this is 78% N2, 21% O2 and 1% other stuff. The normal CO2 level in air is 0.04%.

If my big 20 lb CO2 cylinder leaked from full to empty, it would release 9 kg of CO2 into the basement The molar mass of carbon dioxide is 0.04401 kg / mol, so that's 205 mol of CO2 released into the basement.

Since CO2 is heavier than O2 and N2, assume the CO2 will displace the the air in the basement so, after the 20 lb cylinder empties, 205/6270 = 3.3% of the basement air will be CO2. (I'm assuming that the turnover of air in the basement is zero, which it isn't in practice)

That's 100x the usual atmospheric level and just above the limit for short-term occupational exposure. Interestingly, it was the brewing industry that persuaded OSHA to up the short-term exposure limit to 30000ppm. If all four tanks conspired to leak from full to empty at the same time (highly unlikely) then it would put the concentration over the 4% CO2 level listed as "immediately dangerous to health."

In the case of a slow leak from one tank with a decent amount of room air turn over, everyone would likely be fine. Given that people are not regularly posting about CO2 toxicity on this forum, any problem is likely to be rare. But, hey, I have 5 smoke/CO alarms in our house and I sleep better for it.

 

[duncan.brown]

Just for fun, I also calculated that if the 22 cu ft O2 tank that I use for oxygenating wort leaked from full to empty, it would leak 623 l = 28 mol of oxygen into the basement. Even if that O2 somehow displaced only N2 from the room air, my O2 level would only be just above the normal 21% and I would not have an unsafe oxygen-enriched environment.

 

[specialkayme]

A scary feeling indeed.

Reminds me of a time I was out on a day business trip in the summer a few years back. I had an empty 5 lb Co2 tank and a hombrew store was in the area I was traveling to. I figured why not just trade it out while I'm running about. Left the full tank in my car, didn't even think about the possibility that it would rupture under the heat, but left the windows cracked just to keep it not swealtering while I was gone. I went into a (longish) meeting. When I came out, papers were all strewn about in my car. At first I thought I was robbed. Nothing missing, doors locked, no broken windows, I was so confused. Drove home, hooked up the Co2 tank to find it was empty. I thought I was sold a dud. Until I realized all the papers in my car and the empty tank was related. I about **** my pants.

I've always treated Co2 tanks since then with SIGNIFICANTLY more respect. My old oxygen administration instructor for lifeguarding used to talk about how if you take a sledge hammer to the opening, it would turn into a rocket. So I made sure to "handle" them with care, but never thought temp would be an issue. How dumb was I.