Topics

Hydrogen safety


Mark Conner N9XTN
 

For those of you new to high-altitude ballooning, I would NOT recommend you fill a large balloon indoors unless you are extremely familiar with the building design, to include whether it can safely dissipate the gas should the balloon rupture or you leak a substantial amount of hydrogen.  Having a bubble of hydrogen well mixed with oxygen and trapped against a ceiling is rarely a good thing.

The NWS shelters used to fill radiosondes have specific design elements to mitigate the dangers of using hydrogen inside, to include a lot of grounding and vents.

While many have handled hydrogen safely for years for balloon launches, there is no point in tempting fate.  

73 de Mark N9XTN


Dennis Klipa - N8ERF
 

I have to agree with Mark.  As a research chemist I used hydrogen in the lab a lot and never had an issue while following all of the safety precautions.  But hydrogen is not without its dangers.  For us balloonists, the danger is one of ignition and the heat it generates as well as the pressure it can build up in enclosed spaces.  The other major issue is that a hydrogen flame is colorless.  You can't see it.  You can only see the distortion of light as it passes through the hot gasses from the flame, much like the shimmering images you see over a hot paved road in the summer.  The gas from a leaky valve or fitting could ignite and you might no know it until part of your body passed through it.  Diligence and awareness is important.

I did a safety demonstration at one of our safety meetings involving hydrogen safety.  I filled up a small latex balloon, a typical party balloon, with a mixture of air and hydrogen.  I used a hand held Tesla Coil to generate the spark to ignite the balloon.  The people in the back of the room could feel the heat and one of the suspended ceiling tiles above the balloon was lifted up.  I had an even larger balloon that was filled only with air, although the audience didn't know it.  They absolutely did not want me to ignite the second larger balloon!!

The most interesting thing I learned in preparation for the demonstration was that I had an extremely difficult time igniting the hydrogen inside of the balloon, even though it contained a flammable mixture.  The reason was, the balloon acted as an electrical insulator and I could not get the high voltage Tesla arc to pass through the balloon.  I had to do two things to ignite the hydrogen with the arc.  First I had to insert a metal nut (as in nut and bolt) inside of the balloon.  That alone was not enough.  I then had to suspend the balloon in a metal ring connected to a laboratory ring stand.  Then I could get the arc to travel though the balloon, to the nut, and then on to the ring stand.  Try as I might, I could not get the arc from the Tesla coil to ignite the flammable mixture of hydrogen inside the balloon without the nut inside, despite the very low ignition energy of 0.02 millijoules.

The other thing in our favor is that when the volume concentration of hydrogen in air is greater than 75%, hydrogen is not flammable.  For most of us that means that there is a small window when we first start filling our balloons when the hydrogen concentration is within the flammable limits of 4% to 75%.  So even if you could get a spark inside of the balloon you would be outside of the flammable range most of the time.  Should the balloon burst for some reason, then you could have a problem should the hydrogen find an ignition source before it could dissipate.  Again the physics is on your side, since, if you are outside, the hydrogen will rise and dissipate quickly, unlike other flammables such as gasoline or even propane.

So with proper precautions and awareness of the hazards, hydrogen can be handled safely.

Best Regards,
Dennis, N8ERF



On Wed, Apr 18, 2018 at 9:36 AM, Mark Conner N9XTN <mconner1@...> wrote:
For those of you new to high-altitude ballooning, I would NOT recommend you fill a large balloon indoors unless you are extremely familiar with the building design, to include whether it can safely dissipate the gas should the balloon rupture or you leak a substantial amount of hydrogen.  Having a bubble of hydrogen well mixed with oxygen and trapped against a ceiling is rarely a good thing.

The NWS shelters used to fill radiosondes have specific design elements to mitigate the dangers of using hydrogen inside, to include a lot of grounding and vents.

While many have handled hydrogen safely for years for balloon launches, there is no point in tempting fate.  

73 de Mark N9XTN



Joe WB9SBD
 

This old file is still available for those interested on the one Group that has used Hydrogen, and ONLY Hydrogen from their first flight back in the 80's

https://groups.io/g/GPSL/files/How%20Near%20Space%20Sciences%20Uses%20Hydrogen.txt

Joe WB9SBD

The Original Rolling Ball Clock
Idle Tyme
Idle-Tyme.com
http://www.idle-tyme.com

On 4/18/2018 11:23 AM, Dennis Klipa - N8ERF wrote:
I have to agree with Mark.  As a research chemist I used hydrogen in the lab a lot and never had an issue while following all of the safety precautions.  But hydrogen is not without its dangers.  For us balloonists, the danger is one of ignition and the heat it generates as well as the pressure it can build up in enclosed spaces.  The other major issue is that a hydrogen flame is colorless.  You can't see it.  You can only see the distortion of light as it passes through the hot gasses from the flame, much like the shimmering images you see over a hot paved road in the summer.  The gas from a leaky valve or fitting could ignite and you might no know it until part of your body passed through it.  Diligence and awareness is important.

I did a safety demonstration at one of our safety meetings involving hydrogen safety.  I filled up a small latex balloon, a typical party balloon, with a mixture of air and hydrogen.  I used a hand held Tesla Coil to generate the spark to ignite the balloon.  The people in the back of the room could feel the heat and one of the suspended ceiling tiles above the balloon was lifted up.  I had an even larger balloon that was filled only with air, although the audience didn't know it.  They absolutely did not want me to ignite the second larger balloon!!

The most interesting thing I learned in preparation for the demonstration was that I had an extremely difficult time igniting the hydrogen inside of the balloon, even though it contained a flammable mixture.  The reason was, the balloon acted as an electrical insulator and I could not get the high voltage Tesla arc to pass through the balloon.  I had to do two things to ignite the hydrogen with the arc.  First I had to insert a metal nut (as in nut and bolt) inside of the balloon.  That alone was not enough.  I then had to suspend the balloon in a metal ring connected to a laboratory ring stand.  Then I could get the arc to travel though the balloon, to the nut, and then on to the ring stand.  Try as I might, I could not get the arc from the Tesla coil to ignite the flammable mixture of hydrogen inside the balloon without the nut inside, despite the very low ignition energy of 0.02 millijoules.

The other thing in our favor is that when the volume concentration of hydrogen in air is greater than 75%, hydrogen is not flammable.  For most of us that means that there is a small window when we first start filling our balloons when the hydrogen concentration is within the flammable limits of 4% to 75%.  So even if you could get a spark inside of the balloon you would be outside of the flammable range most of the time.  Should the balloon burst for some reason, then you could have a problem should the hydrogen find an ignition source before it could dissipate.  Again the physics is on your side, since, if you are outside, the hydrogen will rise and dissipate quickly, unlike other flammables such as gasoline or even propane.

So with proper precautions and awareness of the hazards, hydrogen can be handled safely.

Best Regards,
Dennis, N8ERF



On Wed, Apr 18, 2018 at 9:36 AM, Mark Conner N9XTN <mconner1@...> wrote:
For those of you new to high-altitude ballooning, I would NOT recommend you fill a large balloon indoors unless you are extremely familiar with the building design, to include whether it can safely dissipate the gas should the balloon rupture or you leak a substantial amount of hydrogen.  Having a bubble of hydrogen well mixed with oxygen and trapped against a ceiling is rarely a good thing.

The NWS shelters used to fill radiosondes have specific design elements to mitigate the dangers of using hydrogen inside, to include a lot of grounding and vents.

While many have handled hydrogen safely for years for balloon launches, there is no point in tempting fate.  

73 de Mark N9XTN




jasonbunwin
 

1. I tried clicking on the link and the page said I wasn't a member to see the article about the club that flew the hydrogen fueled balloon since the 80s.

2. From what I can gather in the conversation, the following safety measures should be taken when dealing with hydrogen:

     A. No smoking.
     B. No spark generating electrical equipment.
     C. Wear gloves. Non cloth to limit production of static electricity?
     D. Cloth cover on ground. That was a point made in the PARK launches.
     E. Don't let the balloon rub on clothing. Shouldn't do that anyway.
     F. FILL OUTDOORS!!!
     G. Use the proper regulator.
     H. Be on the lookout for a clear flame.
     I. Slowly release the gas. Don't open it "wide open".

3. Did I miss anything?

4. I am sharing with others in our planning process.

5. Is there anyone in this group from Oklahoma willing to help?

Sincerely,

Jason Unwin
KF5UEF


AE5IB (Kip)
 

The purpose of the cloth cover on the ground was to prevent any sharp sticks, stones, or weeds from poking into the balloon before it got light enough to support itself.   We did not want holes or weak spots.

We used disposable gloves because we did not want oil from fingers to cause a weak spot and let the balloon pop earlier.

We also try to wear long sleeves and hoods because we think the danger is not the explosion, if it catches on fire,  but burning pieces of latex falling down on you. Art least that is our theory. No evidence to back it up.

Kip AE5IB
PARK


On Wed, Apr 18, 2018 at 7:19 PM, jasonbunwin via Groups.Io <jasonbunwin@...> wrote:
1. I tried clicking on the link and the page said I wasn't a member to see the article about the club that flew the hydrogen fueled balloon since the 80s.

2. From what I can gather in the conversation, the following safety measures should be taken when dealing with hydrogen:

     A. No smoking.
     B. No spark generating electrical equipment.
     C. Wear gloves. Non cloth to limit production of static electricity?
     D. Cloth cover on ground. That was a point made in the PARK launches.
     E. Don't let the balloon rub on clothing. Shouldn't do that anyway.
     F. FILL OUTDOORS!!!
     G. Use the proper regulator.
     H. Be on the lookout for a clear flame.
     I. Slowly release the gas. Don't open it "wide open".

3. Did I miss anything?

4. I am sharing with others in our planning process.

5. Is there anyone in this group from Oklahoma willing to help?

Sincerely,

Jason Unwin
KF5UEF



Jason Unwin
 

PARK used a regular "Walmart" tarp most of the time. One of the members recommended cloth. Latex gloves were used all the time to not mess up the ballon. Cloth gloves were also used. Long sleeved clothes is a new one.

Jason Unwin
KF5UEF


Hank Riley
 

I'll send you the file in a minute.  Mentioning that here and now
so that others won't have to bother and you won't get a bunch of
similar emails containing the file.

Not sure if it's the sort of thing that needs to be posted
and therefore received by everyone who has email delivery.


From: jasonbunwin via Groups.Io <jasonbunwin@...>
To: gpsl@groups.io
Sent: Thursday, April 19, 2018 12:19 AM
Subject: Re: [GPSL] Hydrogen safety

1. I tried clicking on the link and the page said I wasn't a member to see the article about the club that flew the hydrogen fueled balloon since the 80s.



Joe WB9SBD
 

That's Interesting.

How can you not be a member and be reading these e mails?

Joe WB9SBD

The Original Rolling Ball Clock
Idle Tyme
Idle-Tyme.com
http://www.idle-tyme.com

On 4/18/2018 7:19 PM, jasonbunwin via Groups.Io wrote:
1. I tried clicking on the link and the page said I wasn't a member to see the article about the club that flew the hydrogen fueled balloon since the 80s.

2. From what I can gather in the conversation, the following safety measures should be taken when dealing with hydrogen:

     A. No smoking.
     B. No spark generating electrical equipment.
     C. Wear gloves. Non cloth to limit production of static electricity?
     D. Cloth cover on ground. That was a point made in the PARK launches.
     E. Don't let the balloon rub on clothing. Shouldn't do that anyway.
     F. FILL OUTDOORS!!!
     G. Use the proper regulator.
     H. Be on the lookout for a clear flame.
     I. Slowly release the gas. Don't open it "wide open".

3. Did I miss anything?

4. I am sharing with others in our planning process.

5. Is there anyone in this group from Oklahoma willing to help?

Sincerely,

Jason Unwin
KF5UEF


Hank Riley
 

Joe,

It's probably a case of not having a groups.io password, which is
not necessary to just get email the way Mark set this group up.

Here's a sample of groups.io wording that mentions that situation:  
"Are you receiving emails from a Groups.io group but have never visited the
Groups.io website? You probably don't have a password set up yet."

To get a file you do have to have a password.  To just receive GPSL
mail, you don't need the password.  I'm guessing a lot of subscribers
here just read the email.

You probably know all of this, but I'm saying it for the benefit of others
who might not.

HR


From: Joe WB9SBD <nss@...>

That's Interesting.

How can you not be a member and be reading these e mails?

Joe WB9SBD



Bill Brown
 

Same goes for these folks....hmmm...safety first? :-)

https://www.youtube.com/watch?v=WtPrIH0T3b0

- Bill WB8ELK


-----Original Message-----
From: Hank Riley via Groups.Io <n1ltv@...>
To: GPSL <GPSL@groups.io>
Sent: Wed, Apr 18, 2018 10:29 pm
Subject: Re: [GPSL] Hydrogen safety

Joe,

It's probably a case of not having a groups.io password, which is
not necessary to just get email the way Mark set this group up.

Here's a sample of groups.io wording that mentions that situation:  
"Are you receiving emails from a Groups.io group but have never visited the
Groups.io website? You probably don't have a password set up yet."

To get a file you do have to have a password.  To just receive GPSL
mail, you don't need the password.  I'm guessing a lot of subscribers
here just read the email.

You probably know all of this, but I'm saying it for the benefit of others
who might not.

HR


From: Joe WB9SBD <nss@...>

That's Interesting.

How can you not be a member and be reading these e mails?

Joe WB9SBD