stanw
Contributor
How easy is it for contaminates to find their ways into your tank? If it is placed close to a car exhaust, etc. will the carbon monoxide find its way into the tank?
Thanks.
Thanks.
Contaminates in tanks?
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Is your tank stored empty?
The pressure inside the tank will keep anything from getting inside.
You may get some gunk on the outside of the valve , but nothing should be able to get in as long as you have 100 psi or more inside.
Jim Breslin
The pressure inside the tank will keep anything from getting inside.
You may get some gunk on the outside of the valve , but nothing should be able to get in as long as you have 100 psi or more inside.
Jim Breslin
Venus
Contributor
I dived out of Plymouth on a hard boat last August on a three day trip, two dives a day
Saturday all was well, Sunday we has some unwell people, Monday we had some unwell people
Wednesday I went to my local lake to rince my kit and needed my cylinder filled
The guy sniffed the air (as they always do) before he filled it and told me I had bad air and would have to drain both cylinders before they were filled by him
I asked to smell another cylinder to compare
Sure enough there was a terrible smell of oil
He told me that it was very common to get traces of oil from the compressor filtered through into a fill
I'm no expert, I don't fully understand it, but there were an awful lot of cylinders waiting to be filled outside the MountBatton center on August Bank Holiday
Saturday all was well, Sunday we has some unwell people, Monday we had some unwell people
Wednesday I went to my local lake to rince my kit and needed my cylinder filled
The guy sniffed the air (as they always do) before he filled it and told me I had bad air and would have to drain both cylinders before they were filled by him
I asked to smell another cylinder to compare
Sure enough there was a terrible smell of oil
He told me that it was very common to get traces of oil from the compressor filtered through into a fill
I'm no expert, I don't fully understand it, but there were an awful lot of cylinders waiting to be filled outside the MountBatton center on August Bank Holiday
You need to find better places to get your tanks filled. There should be no Oil smell... ever...and if you did, you should have the inside of the tank inspected and maybe cleaned.
And I am not sure what to make of someone smelling the air before filling the tank....even that concerns me...
And I am not sure what to make of someone smelling the air before filling the tank....even that concerns me...
seems like good practice to me - they don't want to accept responsibility for a bad fill done by someone else.
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Agreed but I suspect few do.
To the OP, there is no way anything is getting into a tank with even a little pressure remaining inside that does not come through a compressor. Look for an air quality certificate at any place you have tanks filled. If they do not have one, find some place that does.
Venus, sound like poor compressor maintenance to me.
To the OP, there is no way anything is getting into a tank with even a little pressure remaining inside that does not come through a compressor. Look for an air quality certificate at any place you have tanks filled. If they do not have one, find some place that does.
Venus, sound like poor compressor maintenance to me.
Gen San Chris
Contributor
I actually sniff my tanks before fillig them but only if they have been rented out as a couple of times I have had rental tanks returned which smell as the people using them have filled them on another compressor which is against my rules! They always deny it anyway but such things do happen!
I change my filter media a bit too much really but for the low cost of it I do not mind!
I change my filter media a bit too much really but for the low cost of it I do not mind!
CO contamination and oil contamination are entirely different things and result from different problems. CO is introduced either by placing the compressor intake near a source of exhaust fumes or by burning the oil in your compressor. Oil contamination is usually accompanied by excessive moisture and is the result of poor filter maintenance.
Generally, it is difficult or impossible to detect the odor of oil in a tank at the fill station if the compressor is in the general vicinity. A small amount of oil from the compressor will be present in the air around the compressor. Anyone in the area will be smelling a small ambient level of oil in the air and their ability to detect an oil smell from a tank will be quite limited.
Generally, it is difficult or impossible to detect the odor of oil in a tank at the fill station if the compressor is in the general vicinity. A small amount of oil from the compressor will be present in the air around the compressor. Anyone in the area will be smelling a small ambient level of oil in the air and their ability to detect an oil smell from a tank will be quite limited.
I mostly agree with the above. However, both contaminates (CO/OIL) are a result of poor filter and/or compressor maintenance.
I dive frequently from boats here in SoCal and getting water in the tank is a much larger issue. Our local boat fills are generally more wet that shop fills. It is just a fact of life here.
The other notion that water or contaminates will or can enter a tank if it is drained below 300 PSI is nonsense. As long as there is more pressure inside the tank in comparison
Good question.
The most common "contaminate" is water. One of the reasons that we have annual cylinder inspections is that back in the 1970s the US Navy discovered widespread corrosion in many of their aluminum cylinders. The Navy contracted with the Battelle Memorial Institute to investigate the problem and one of Battelle's recommendations was scheduled cylinder inspections.
How does water get into the cylinders? It is clear that water will enter a cylinder if a tank is taken underwater, drained to zero PSI and then the second stage purge button is depressed. But that's not the most common cause.
I would say that the most common reason water enters a cylinder is because the cylinder valve is wet when the fill whip is connected. High-pressuire air from the compressor pushes this moisture into the cylinder when the valve is opened.
The second most common cause is probably bad filters on the compressor. Although the compression process removes most of the water vapor, if the fill station operator doesn't change the filters at appropriate intervals you may get a "wet" fill.
How about other contaminates such as carbon monoxide? Numerous deaths have been attributed to "bad air" and carbon monoxide contamination from faulty compressors, faulty filters and idling vehicles near the compressor intake. Unless you check your cylinders for carbon monoxide with a detector, you'll never know. Fortunately problems such as this are very rare.
Oil is another contaminate, usually indicative that there's something wrong with the compressor and filters.
So the answer is that it's very easy to get contaminates in your cylinder. You can minimize the risks by using a reliable fill station, smelling your gas, keeping your cylinder inspections up-to-date and analyzing your gas when appropriate.
The most common "contaminate" is water. One of the reasons that we have annual cylinder inspections is that back in the 1970s the US Navy discovered widespread corrosion in many of their aluminum cylinders. The Navy contracted with the Battelle Memorial Institute to investigate the problem and one of Battelle's recommendations was scheduled cylinder inspections.
How does water get into the cylinders? It is clear that water will enter a cylinder if a tank is taken underwater, drained to zero PSI and then the second stage purge button is depressed. But that's not the most common cause.
I would say that the most common reason water enters a cylinder is because the cylinder valve is wet when the fill whip is connected. High-pressuire air from the compressor pushes this moisture into the cylinder when the valve is opened.
The second most common cause is probably bad filters on the compressor. Although the compression process removes most of the water vapor, if the fill station operator doesn't change the filters at appropriate intervals you may get a "wet" fill.
How about other contaminates such as carbon monoxide? Numerous deaths have been attributed to "bad air" and carbon monoxide contamination from faulty compressors, faulty filters and idling vehicles near the compressor intake. Unless you check your cylinders for carbon monoxide with a detector, you'll never know. Fortunately problems such as this are very rare.
Oil is another contaminate, usually indicative that there's something wrong with the compressor and filters.
So the answer is that it's very easy to get contaminates in your cylinder. You can minimize the risks by using a reliable fill station, smelling your gas, keeping your cylinder inspections up-to-date and analyzing your gas when appropriate.
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