What is the Source of Strange Sewer-Like Fumes Causing Reactions?

In summary, the conversation discussed the use of metal for creating airtight seals on jars, and whether the expansion of metal could compromise its airtight properties. It was also mentioned that the airtight property of containers is not due to metal-to-metal or metal-to-glass seals, but rather an intermediate layer that helps to make the seal work. The rate of gas diffusion is determined by temperature and pressure, rather than tension in the metal or glass. There was also a discussion about the permeability of gases, particularly hydrogen, through different materials. Finally, the conversation touched on the use of materials to block sewage gases and the issue of diffusion in containers.
  • #1
moriah
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TL;DR Summary
When a metal expands, does it loose it’s airtight property?
I am in the need of airtight materials. Naturally, metal came to my mind. Metal is used in jar tops to create “airtight” seals. However, as I contemplated how the tops must expand slightly as they are screwed down towards the glass part of the jars, I wondered if this expansion compromises the inherent airtight property of the metal.
 
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  • #2
The airtight property that you are mentioning for those containers is not due to metal-to-metal seals or metal-to-glass seals. When you take those lids off, do you notice an intermediate layer (maybe thin) that helps to make the seal work?
 
  • #3
Hydrogen and helium gas can move through glass and some metals. Bigger gas molecules do not.
The rate of diffusion is more determined by the temperature and pressure of the gas than it is the tension in the metal or glass.
 
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  • #4
berkeman said:
The airtight property that you are mentioning for those containers is not due to metal-to-metal seals or metal-to-glass seals. When you take those lids off, do you notice an intermediate layer (maybe thin) that helps to make the seal work?
I’ve never tried sealing with these jars. I’ve watched others do it. However I would be skeptical of any thin material creating an airtight seal. Also, the question of expanding metal still remains, for example when metal is heated. Would this create microscopic gaps in the metal allowing air to pass?
 
  • #5
moriah said:
I’ve never tried sealing with these jars. I’ve watched others do it. However I would be skeptical of any thin material creating an airtight seal. Also, the question of expanding metal still remains, for example when metal is heated. Would this create microscopic gaps in the metal allowing air to pass?
Baluncore said:
Hydrogen and helium gas can move through glass and some metals. Bigger gas molecules do not.
The rate of diffusion is more determined by the temperature and pressure of the gas than it is the tension in the metal or glass.
Okay I just saw your reply. I think you answered my question.
 
  • #6
I stand corrected. Upon researching, I found some information about thin nitrite material being able to block even helium, but not necessarily hydrogen because hydrogen can oxidize surfaces, hence erode them.
berkeman said:
The airtight property that you are mentioning for those containers is not due to metal-to-metal seals or metal-to-glass seals. When you take those lids off, do you notice an intermediate layer (maybe thin) that helps to make the seal work?
 
  • #7
It is important that the contained food does not react chemically with the lining of the container.
 
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  • #8
Use food grade 304 stainless steel.
Metal expansion does not cause voids at the grain boundaries afaik. If it did, I might be concerned about a few pressure vessels I have made over the last 35 years.
 
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  • #9
Do you know if gases can permeate such as hydrogen?
 
  • #10
moriah said:
Do you know if gases can permeate such as hydrogen?
Hydrogen gas can migrate or diffuse through many metals such as platinum. Other gasses do not migrate as rapidly. Thick walls, low temperature, and low pressure differences will reduce the flow.

With zero pressure difference there will still be diffusion of hydrogen through a cap on a jar, but there will probably be more through the glass wall of a jar. For a perfect seal against hydrogen you will need a double wall container with a "getter", a chemical to absorb hydrogen between the two walls. Perfection is the enemy of progress. How much hydrogen migration can you tolerate ?
 
  • #11
Baluncore said:
Hydrogen gas can migrate or diffuse through many metals such as platinum. Other gasses do not migrate as rapidly. Thick walls, low temperature, and low pressure differences will reduce the flow.

With zero pressure difference there will still be diffusion of hydrogen through a cap on a jar, but there will probably be more through the glass wall of a jar. For a perfect seal against hydrogen you will need a double wall container with a "getter", a chemical to absorb hydrogen between the two walls. Perfection is the enemy of progress. How much hydrogen migration can you tolerate ?
I’m studying materials because I’m trying to block sewage gases, namely hydrogen sulfide.
 
  • #12
moriah said:
I’m studying materials because I’m trying to block sewage gases, namely hydrogen sulfide.
H2 has a bond length of 74 pm. H2S is bigger with a bond length of 135 pm.

Gas diffusion is proportional to the inverse square root of the mass. H2 has a mass of 2. H2S has mass 34. So hydrogen will travel over 4.1 times faster than H2S, and it will fit through smaller holes.

Under what situations do you have a problem with diffusion of H2S out of or into a container ?
 
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  • #13
It’s not a container issue. It’s a dwelling issue. I’m trying to amass information to possibly develop customized sub-flooring and foundation.
 
  • #14
I’m trying to amass information to possibly develop customized sub-flooring

Yikes! I wouldn't want to live in a building that depended on sub-flooring to separate me from sewer gas.

Can you explain why you are building on top of sewer gas?
 
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  • #15
Gases escape from sewage pipes into dwellings, more than not. The vast majority of the population doesn’t perceive it, most likely due to an inbuilt immunity. I don’t have this immunity and therefore, in addition to finding materials to seal the pipes themselves, the flooring would be an added layer.

The problem with sealing the pipes is that, for example, nitrile is proported to resist all gases, even hydrogen. However, this is not what I experience with nitrile. There is also closed cell foam spray, which I am yet to try, but I am skeptical.
 
  • #16
moriah said:
It’s not a container issue. It’s a dwelling issue.
I guess the concentration of H2S in groundwater is irrelevant, as given time, H2S will diffuse into a basement to form a stagnant pool of hazardous vapour.

The rate of diffusion could be reduced by a water proof polyethylene film, which is resistant to damage by H2S. The H2S molecular bond (135 pm) is bigger than H2O (95 pm), so how quickly will H2S diffuse through or around a PE film to enter a building through the floor?

Methane and H2S are fuels for sewer and underground mine explosions. Fundamentally this is going to come down to ventilation issues. 1. Ventilation of sewers; 2. Ventilation of the soil, and 3. Ventilation of enclosed dwelling spaces.

Drainage of water from foundations, so air can circulate through the soil and vent H2S externally to the atmosphere is a possible remedy. Consider drilling a hole or a sump in the floor of the basement, pump water out of the Earth below the dwelling to lower the water table, while pushing air in continuously above the water table, should resolve the H2S problem. The size of the pumps required could be very low power.

Who would have thought that the pilot lamp of a boiler in the basement, a candle or a fire in a fireplace with a chimney could be so beneficial to controlling methane, H2S and Radon in the basement.
 
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  • #17
You have the best answers. You are my rock🙂. However, you lost me on the pilot light, fire, etc. Are you suggesting these sources of heat are burning the gases, therefore making them dissipate, or are you being facetious?
 
  • #18
moriah said:
You have the best answers.
That is all part of the service here at PF, once you ask the right question.

moriah said:
Are you suggesting these sources of heat are burning the gases, therefore making them dissipate, ...
Yes, and carrying them up the chimney.

Modern houses are insulated, to the point of being airtight, which may be a real problem without a counter-flow heat-exchanger as part of the ventilation.

Another possibility would be an ozone (O3) generator in the basement. Ozone would convert H2S into SO2. Would ozone and SO2 or sulfuric acid be worse than H2S?
https://en.wikipedia.org/wiki/Ozone#With_sulfur_compounds
Maybe it is worth doing that experiment. To generate ozone, a germicidal UV lamp, or a corona discharge ion generator could be used, as seen cheap on eBay, as is used to remove the smell of eggs that builds up in a refrigerator.

Or you might go very low-tech and low-cost, just burn one joss stick each day to hide the odor of everything.
 
  • #19
Sulfuric acid is probably just as corrosive to the lungs as hydrogen sulfide. Ozone is not as scary.
I’m trying to keep the gases from entering period. The best option would be a mobile home. If and when I try the polyethylene foam spray, I will tell you about the results. The information about the stainless steel is also encouraging. I would like to use it as a “foundation” material, even just as a loose sheet, just to see if it works.
 
  • #20
The average human can detect the odour of half a part per billion of H2S. You claim to be more sensitive than average, so you should not be scared, even if all that H2S was converted by ozone to SO2 or H2SO4 in the air. There is already very much more SO2 or H2SO4 in the environment from motor vehicles.
 
  • #21
moriah said:
I’m studying materials because I’m trying to block sewage gases, namely hydrogen sulfide.
Are you absolutely sure that the sewage gases are coming up through the ground? There are other sources that are more likely. The most likely is a dry P trap. All plumbing fixtures have P traps. The diagram below shows a P trap under the basin, while the toilet has the trap built inside. The vent stack connects down to the soil stack which is connected to the sewer, and connects up to an open pipe above the roof. If a fixture is not used for a period of time, usually more than a month, the water in the trap evaporates and sewer gases enter the building. If you have any sinks, toilets, shower pans, or bathtubs that have not been used for some time, pour a quart of water into them and/or flush the toilet.

Another likely source is the stack vent on the roof. If you go onto the roof of any house and get close to a stack vent, you will notice a strong sewer gas odor. Air currents could be moving those gases to an air intake. It is good practice to check roof vent stacks to make sure they are not plugged with a dead bird or something.
Plumbing vent.jpg

Another source is the gasket under the toilet. Older toilet installations use a wax gasket between the toilet and the waste pipe. That gasket can leak. If the toilet moves when sitting on it, even a tiny little bit of rocking, then that gasket is leaking water out and sewer gas in. Be advised that a rocking toilet normally requires replacing the rotted wood that caused the rocking. A lesson I learned the hard way.

If it is an older house, there may be problems in the plumbing. My first house came with the toilet plumbed down to a tee in the sewer pipe. One branch of the tee flowed out to the city sewer, the other branch was underground and open. There was a root mass from under the foundation and ten feet into the pipe. The toilet worked better after I pulled out the root mass and plugged the opening in the tee.

Old style sewage piping was made of cast iron. The lead joint packing can leak.
 
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  • #22
Yes, I know all this. I wish it was this simple. Unfortunately, they are gases to which I react in ALL dwellings, in all parts of the country. It’s more of a phenomenon than a common problem.
 
  • #23
Since I’ve already divulged many circumstances, I should also tell you that there are others who are reacting in similar ways as me. When I searched Amazon for a methane meter, a couple of reviewers wrote about how they smell sewage and we’re having gas poisoning symptoms. When they called the fire department to measure the air, their detector didn’t sense anything. Yet the $30 and $100 meters were going off like crazy. The same exact thing happened to me, fire department and all. The fire department’s detector is supposedly thousands of dollars. Anyway, I wrote the EPA about it.
 
  • #24
The only success I’ve had in sealing a floor from these gases was on a linoleum/vinyl floor, using grout sealant in the aerosol form.
 
  • #26
Yes, I agree with my buddy, Baluncore, about almost everything except for that post. To his/her credit, I know he/she is trying to help me.
 
  • #27
moriah said:
When they called the fire department to measure the air, their detector didn’t sense anything. Yet the $30 and $100 meters were going off like crazy. The same exact thing happened to me, fire department and all. The fire department’s detector is supposedly thousands of dollars.
I think I would trust the Fire Department's meters more than inexpensive commercial devices. Did the FFs tell you what-all their meters were able to check for?

https://www.firehouse.com/rescue/hazardous-materials/article/21072993/hazmat-detection-detail
Another critical step is deploying various types of detection equipment as soon as a gas hazard is suspected. As I noted, in Philadelphia, our EMS bags all have CO detectors attached to them. The simple reasoning is that we take that bag on the vast majority of calls we respond to and it helps keep our members from being caught off guard by a colorless, odorless killer gas.

From that simple but effective CO detector, we move to more sophisticated meters. Philadelphia battalion chiefs are all equipped with multi-gas meters that measure parts per million (ppm) and lower explosive levels (LEL) of natural gas, CO, hydrogen sulfide (H2S) and oxygen. These meters are easy to use and sound an audible alert when gases are detected in the explosive range.

For the vast majority of the “run-of-the-mill” fumes calls we get, these meters do a great job. But when things move up to the next level, we call in the big guns—the hazardous materials teams. They’re equipped with more sophisticated air-monitoring equipment like five-gas meters. These sensitive meters give us a much more detailed assessment of what we are dealing with.
 
  • #28
Who knew you were a fireman?! This is an awesome coincidence. Yes most people would naturally trust the fire department’s detectors. However, even the layperson cannot deny the many other “coincidences” in the circumstances that I described in the last post. I don’t have any doubt that there is a breakthrough that is going to arise from these findings. I’m trying to purchase one of the $100 meters so it can give me a ppm reading.
 
  • #29
moriah said:
I’m trying to purchase one of the $100 meters so it can give me a ppm reading.
Of ## H_2S##?
 
  • #30
I purchased a H2S meter in 2020. Didn’t yield any results. It was like $150. I returned it. I didn’t realize until this year, that it could also be methane. I bought a natural gas meter for $30 this year and it beeped to the highest level. I took a video, then returned it. Now I’m trying to purchase a natural gas/methane/propane meter that gives ppm readings.
 
  • #31
And then return it?
 
  • #32
No, this one would be a keeper. I tried to attack the video but this site only attaches photos.
 
  • #33
Do you know if the multi-gas detectors that firemen use, can detect carbon disulfide?
 
  • #34
Why do you ask?
 
  • #35
E4475FC8-BDD4-4A6A-A7B9-B4BBAED89CB1.jpeg
 

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