Method Exit bag and inert gas megathread

[iamgood]

Hydrogen's flammability range in air is 4 - 75%. In order to ignite the mixture 5% H2 / 95% N2, you'd have to add pure oxygen to it. Air either won't provide a sufficient concentration of O2 for ignition or will dilute that small percent of H2 to a non-flammable gas mixture.

i read that at high pressure, at the gas outlet, there is a possibility of explosion due to spark from friction or static electricity. Its better to be safe than sorry. Especially if there is a oil or lubricants near the regulator. I wouldn't do it even if there is a 0.1 percent chance of happening.

 

[quietbird]

hey. Dont use anything containing hydrogen. highly explosive and will seriously injure u and others around you.

Thank you, ahhh!

 

[Intoxicated]

i read that at high pressure, at the gas outlet, there is a possibility of explosion due to spark from friction or static electricity.

Any real examples of that happening with 5% H2 gas? Theoretically, it's probably possible to ignite such dilute hydrogen with air at elevated pressures, but I hardly imagine how you could produce a spark inside before nearly all residual air there would be displaced by the stream of N2/H2 mixture.

Its better to be safe than sorry. Especially if there is a oil or lubricants near the regulator.

What exactly could oil or lubricants do? They might easily ignite if the tank were charged with oxygen, that is not the case here however.

I wouldn't do it even if there is a 0.1 percent chance of happening.

0.1% is a too big chance for a single use. I guess, the real odds of ignition do not exceed those you have when refueling your car at a gas station.

 

[iamgood]

Any real examples of that happening with 5% H2 gas? Theoretically, it's probably possible to ignite such dilute hydrogen with air at elevated pressures, but I hardly imagine how you could produce a spark inside before nearly all residual air there would be displaced by the stream of N2/H2 mixture.

What exactly could oil or lubricants do? They might easily ignite if the tank were charged with oxygen, that is not the case here however.

0.1% is a too big chance for a single use. I guess, the real odds of ignition do not exceed those you have when refueling your car at a gas station.

yes, the chances are extremely low, but if i can avoid something that can theoretically cause something as destructive as hydrogen explosion, i would avoid that so that i have peace of mind. Since i have so many anxieties, i neither drive car nor go near to any flammable cylinders such as propane, o2 or hydrogen, gas station, etc :)

 

[Intoxicated]

Safety data sheets for H2 5% / N2 95% mixture describe it as non-flammable and label it with the corresponding green diamond

https://elmemesser.lt/wp-content/uploads/sites/3/2021/01/Formiergas-H5_ENG.pdf

https://www.sgsgases.co.uk/wp-content/uploads/2022/01/Leak-Trace-English-v2.0.0.pdf

https://datapool.tecnogas.net/system/uploads/attachment/data/3020/16191394/msds_Safety_Data_Sheet_Sku_11259_11284.pdf

 

[iamgood]

Safety data sheets for H2 5% / N2 95% mixture describe it as non-flammable and label it with the corresponding green diamond

View attachment 166478

https://elmemesser.lt/wp-content/uploads/sites/3/2021/01/Formiergas-H5_ENG.pdf

https://www.sgsgases.co.uk/wp-content/uploads/2022/01/Leak-Trace-English-v2.0.0.pdf

https://datapool.tecnogas.net/system/uploads/attachment/data/3020/16191394/msds_Safety_Data_Sheet_Sku_11259_11284.pdf

please read this safety sheet. its labelled red, with fire symbol.

5% Hydrogen/Argon, BS4 valve, 10 litre (AV Size), Aluminium cylinder, C Certificate (+/-5%), 200 Bar - Size AV (2.07m3) | Industrial Gas | Gas Equipment & Accessories | BOC Shop

 

[Intoxicated]

My guess is that hydrogen and argon don't form sufficiently uniform distribution in the cylinder due to too high difference in density of these two gases. Hence when you release some part of the gas mixture (which may come mostly from the upper part of the cylinder), the proportion of H2 there may significantly exceed the average 5%, implying the possible flammability.

 

[iamgood]

My guess is that hydrogen and argon don't form sufficiently uniform distribution in the cylinder due to too high difference in density of these two gases. Hence when you release some part of the gas mixture (which may come mostly from the upper part of the cylinder), the proportion of H2 there may significantly exceed the average 5%, implying the possible flammability.

could be, but also nitrogen 95 % and hydrogen 5 % in some western European countries also have fire symbol, red color, different valve. So, yes, although its less likely to have an explosion with 5 or less than 5 % hydrogen, there is a real possibility of explosion which will be catastrophic. So, its better to be safe than sorry when someone can easily avoid that by just buying cylinder without hydrogen. we already have so many other things to worry :)

 

[Intoxicated]

but also nitrogen 95 % and hydrogen 5 % in some western European countries also have fire symbol, red color

That could be determined by bias when measuring 5%. F.e., 5% ± 0.01% is likely non-flammable, but 5% ± 1% could be potentially flammable.

So, its better to be safe than sorry when someone can easily avoid that by just buying cylinder without hydrogen. we already have so many other things to worry :)

I think, it's better to read the relevant data sheet for the purchased product and not panic about flammability prematurely.

 

[iamgood]

That could be determined by bias when measuring 5%. F.e., 5% ± 0.01% is likely non-flammable, but 5% ± 1% could be potentially flammable.

I think, it's better to read the relevant data sheet for the purchased product and not panic about flammability prematurely.

You are right, its better to read relevant data sheet. But, since i have lot of anxiety, i take too many precautions, and working with hydrogen cylinder is too much for me. For you and for most others it wont be an issue to be near a hydrogen cylinder at high pressure.

Even with 1 percent hydrogen and 99 percent nitrogen, the color and info and regulators are completely different. For privacy reasons, i dont want to name the country or company. So, i can send you a DM, but your privacy settings dont allow me. :)