AvGas sniff Test

Jaybird180

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With recent threads and the excellent testing of one of our members there is a resurgence in consciousness about fuel quality.

My Primary CFI showed me how to do a preflight, which included a sniff test for the fuel. At the time, I believed there were other ways of verifying that it is in-fact AvGas and have not put the stuff to my nose since. Well, I'm rethinking that practice and the lack thereof - I see no one smelling sample jars; it does look strange to see a guy smelling the gas.

The questions for discussion:
1) is the lead in 100LL aerosolized?
2) are there other chemicals in AvGas that are known to the State of California (sarcasm) to cause cancer (or other illness by olfactory exposure?
 
1. This is a great question. I would guess the lead in fuel is not readily airborn until it is burned.
2. Yes.
 
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I'm not sure how bad smelling the stuff all the time is for you, but I'm sure it isn't good for you either. I worked as a line guy for about 8 years and avoided smelling and touching the stuff at all costs.

I fueled many 421s and 414s when I worked there and they have the large fuel caps(similar to a jet) so the duck bill nozzle on a jet truck will fit in it(that had to be one new and stupid line guy though). For your plane, even the small jet nozzle for helicopters won't fit in a Skyhawks fuel openings.

Best ways to prevent an inadvertent fueling of jet fuel or other fueling mistakes?

Keep your hangar locked - so your plane doesn't get fueled by mistake(oh you said hangar 41? I thought you said hangar 14!)

Get lockable fuel caps for your plane and keep the keys on the ignition key chain - This could prevent someone from stealing your gas from you too. Probably over $200 sitting in the tanks of a 172 alone.

Always supervise the fueling - Some FBOs may round up to the nearest gallon to charge you a little extra money as well when you aren't looking. Or worse. A jet pilot accidentally got charged for 960 gallons instead of 690. He signed the receipt and put it in his pocket like it was nothing. The customer service rep caught it before he left and fixed the transaction. He got the amount he ordered, but sometimes even that gets mixed up due to poor communication.

All three of those examples I have either seen first hand or heard of people doing. People make mistakes. Whenever I fly somewhere civilian, I supervise the fueling. I don't care if the line guy assumes I think he is incompetent. It is my life on the line if he screws up, not his. If you actively take part in the refueling, there should be no question what is in the tanks and you shouldn't even have to sniff test it.
 
I recently switched to MoGas - the only thing I mis from AvGas is the sniff test: MOGAS STINKS!

But yea, I personally have a problem with the lead. We are more than capable of getting rid of that stuff. If for no other reason: my spark plugs will thank me! It's all politics and economics at this point.
 
Terra ethyl lead evaporates about as fast as jet fuel. Which is to say, rather slowly. I say this because the vapor pressures of both are about the same, 0.2 vs 0.4 mm mercury, at room temp, for TEL and kerosene, respectively.

For comparison, alcohol has a vapor pressure of about 40 mm, so it evaporates much faster.

The EPA has guidelines on breathing TEL, about 0.1 mg per cubic meter, but I have no idea whether you will exceed them with a sniff.
http://www.cdc.gov/niosh/docs/81-123/pdfs/0601.pdf
 
brian];1557567 said:
I recently switched to MoGas -
You did? I've seen airplanes sit for months if not years and start right up. On the other hand, I've had to clean the gum out of the float bowl in my lawn mower after a winter in the shed. A local formula car owner puts avgas in his car during winter storage. Just sayin'...

dtuuri
 
The questions for discussion:
1) is the lead in 100LL aerosolized?
2) are there other chemicals in AvGas that are known to the State of California (sarcasm) to cause cancer (or other illness) by olfactory exposure?

I would suggest that one not make a habit of sniffing gas. It definitely isn't in our evolutionary heritage so the body probably isn't well equipped to deal with refined hydrocarbons and other toxins. On the other hand, I've been exposed to a lot of crude oil and refined products and made it this far so the body is obviously tolerant. If you're concerned with possible contamination then go with the paper test.

End of the day I like the suggestion to always supervise fueling and plan to stop letting FBO's fuel when I'm not there. It's only happened a few times but it only takes once. It'll be a pain at a busy fbo but it'll just have to be that way.
 
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1.Do not know
2.Do not know, but I am sure drinking wine is not good for my liver but I do it anyway.

The reason I do the “Sniff Test” is because one day when drawing a preflight sample of fuel the color of the fuel was not light blue. I sniffed it and there was no smell. The second sample was the same. Some how, I had a half gallon of water in both tanks. From that point on I always do a sniff test just to make sure.
 
Yes, gasoline vapors are toxic and at least slightly carcinogenic.

No, you are not going to get cancer from a quick sniff in a fuel jar a couple of times a week. If you work a refinery job or pump gas for a living for 20 years, you might have cause to worry.
 
...I've been exposed to a lot of crude oil and refined products and made it this far so the body is obviously tolerant.
Yeah, but you're at death's door. Read the CDC report, they're talking about your posts on POA:

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dtuuri
 

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oh look, I have a stalker...isn't that just lovely
 
Can't say much except that it's unpleasant to smell repeatedly.

A month or so ago I was refilling the avgas truck (sitting on top of the truck with the nozzle for 30-45 minutes). 900 gallons or something later, I tried to get up and I felt drunk. I was sitting as far away from the hole as I could while still seeing inside and it was awful. 10/10 would not recommend. Checked the SDS and it said to not prolong exposure to the fumes but other than that, it wasn't terrible.
 
You did? I've seen airplanes sit for months if not years and start right up. On the other hand, I've had to clean the gum out of the float bowl in my lawn mower after a winter in the shed. A local formula car owner puts avgas in his car during winter storage. Just sayin'...

dtuuri

Yea, something to watch for - but so far so good. I'm a bit lazy and would probably pay the extra $$s (well, until I added it up), but there is an "E-Series Bonanza" guru that claims over 30,000 gallons over the past few decades have went through his G35 with no issues. I've talked with a couple of other early Bo owners that have been running mogas for years with the same results.

I guess the key is always: don't let it sit, and fly often. I guess my weed eater gummed up due to inactivity - and will likely continue to be a problem as I would rather go flying anyway :)
 
brian];1558004 said:
Yea, something to watch for - but so far so good. I'm a bit lazy and would probably pay the extra $$s (well, until I added it up), but there is an "E-Series Bonanza" guru that claims over 30,000 gallons over the past few decades have went through his G35 with no issues. I've talked with a couple of other early Bo owners that have been running mogas for years with the same results.

I guess the key is always: don't let it sit, and fly often. I guess my weed eater gummed up due to inactivity - and will likely continue to be a problem as I would rather go flying anyway :)

In 4 years of ownership I haven't had the problem with my 2-stroke Ryobi.
 
Can't say much except that it's unpleasant to smell repeatedly.

A month or so ago I was refilling the avgas truck (sitting on top of the truck with the nozzle for 30-45 minutes). 900 gallons or something later, I tried to get up and I felt drunk. I was sitting as far away from the hole as I could while still seeing inside and it was awful. 10/10 would not recommend. Checked the SDS and it said to not prolong exposure to the fumes but other than that, it wasn't terrible.
A quick search on "huffing gasoline"...
 
A quick search on "huffing gasoline"...

To be strictly correct, though, the hypothetical sniff test being discussed here is not the same as 'huffing gasoline' to get high. It is not the same in vapor concentration in the lungs, quantity of vapor exposure, frequency of exposure, or time between exposures, long-term exposure, etc.
 
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This is not the same as 'huffing gasoline' to get high. It is not the same in vapor concentration in the lungs, quantity of vapor exposure, frequency of exposure, or time between exposures.

Settin' on top of the truck looking in the hatch while filling the big tank is pretty close to huffing. Sniffing the sample jar using proper technique certainly isn't. Note the proper technique is the one you learned in chemistry lab where one uses a hand to "wave" the fumes over to be smelled rather than holding the sample up to the nose.
 
Settin' on top of the truck looking in the hatch while filling the big tank is pretty close to huffing. Sniffing the sample jar using proper technique certainly isn't. Note the proper technique is the one you learned in chemistry lab where one uses a hand to "wave" the fumes over to be smelled rather than holding the sample up to the nose.

Perhaps, but that is still a one-time exposure, not repeated to maintain the high so to speak, nor is it (hopefully) repeated day after day.

Also, that is not the same thing as the sniff test being discussed here.
 
It was totally accidental, I was sitting as far back as I could and leaning away from the opening (up wind mind you) and it ended up still wrecking me. Not quite on topic but it definitely screws with your head if you breathe too much of the stuff. Once I got away to fresh air I recovered pretty quickly.
 
Sample fuel, look for bubbles of water, hold it up against something white, verify color, dispose as appropriate. You don't need to sniff it; that said if it's avgas you'll smell it just by sumping it. Unless someone is contaminating your fuel with water with food coloring, the color test is sufficient.

On a related note, if the plane burns both mogas an avgas, expect some interesting shades and smells of fuel as the nasty mogas mixes with the nice avgas.
 
Sample fuel, look for bubbles of water, hold it up against something white, verify color, dispose as appropriate. You don't need to sniff it; that said if it's avgas you'll smell it just by sumping it. Unless someone is contaminating your fuel with water with food coloring, the color test is sufficient.

On a related note, if the plane burns both mogas an avgas, expect some interesting shades and smells of fuel as the nasty mogas mixes with the nice avgas.

If you check out the other thread about contamination with Jet A here: http://www.pilotsofamerica.com/forum/showthread.php?t=74702&highlight=Contamination

you'll learn that's not sufficient.

Short version: Jet A mixed with 100LL is still blue.
John
 
Sample fuel, look for bubbles of water, hold it up against something white, verify color, dispose as appropriate. You don't need to sniff it; that said if it's avgas you'll smell it just by sumping it. Unless someone is contaminating your fuel with water with food coloring, the color test is sufficient.

On a related note, if the plane burns both mogas an avgas, expect some interesting shades and smells of fuel as the nasty mogas mixes with the nice avgas.

This thread showed specifically that the color test is *not* a reliable indicator of Jet A in 100LL up at a 50/50 mix.

Edit: yeah sorry not this thread but the Jet A in Avgas thread.
 
I would suggest that one not make a habit of sniffing gas. It definitely isn't in our evolutionary heritage so the body probably isn't well equipped to deal with refined hydrocarbons and other toxins. On the other hand, I've been exposed to a lot of crude oil and refined products and made it this far so the body is obviously tolerant. If you're concerned with possible contamination then go with the paper test.

End of the day I like the suggestion to always supervise fueling and plan to stop letting FBO's fuel when I'm not there. It's only happened a few times but it only takes once. It'll be a pain at a busy fbo but it'll just have to be that way.

I sniff every time, every tank. I had an engine failure on the runway because after sampling, I looked and saw no water, but the truth was that it was ALL water due to a faulty gas cap gasket.

I sniff every time, every tank and I teach my daughter to do the same thing.

Do what you want :)
 
I sniff every time, every tank. I had an engine failure on the runway because after sampling, I looked and saw no water, but the truth was that it was ALL water due to a faulty gas cap gasket.

I sniff every time, every tank and I teach my daughter to do the same thing.

Do what you want :)

Holy cow all water? What type aircraft?

I was about to say that ordinarily a sniff test wouldn't detect water but damn looks like you found the exception, :hairraise:
 
Sample fuel, look for bubbles of water, hold it up against something white, verify color, dispose as appropriate. You don't need to sniff it; that said if it's avgas you'll smell it just by sumping it. Unless someone is contaminating your fuel with water with food coloring, the color test is sufficient.

On a related note, if the plane burns both mogas an avgas, expect some interesting shades and smells of fuel as the nasty mogas mixes with the nice avgas.

If you check out the other thread about contamination with Jet A here: http://www.pilotsofamerica.com/forum/showthread.php?t=74702&highlight=Contamination

you'll learn that's not sufficient.

Short version: Jet A mixed with 100LL is still blue.
John

:yeahthat:
 
Holy cow all water? What type aircraft?

I was about to say that ordinarily a sniff test wouldn't detect water but damn looks like you found the exception, :hairraise:

PA 28-140. had been sitting out in the rain all week. Pulled 1.5 qts. out of the tank that I was pulling off of, none in the other tank. Fun times.

Additionally, I heard a similar thing happen to a 5000 hr. Bo driver going to a FAAST seminar (ironic, huh). Took off, big slug of water stopped the engine 300 ft up. tried to turn back to the airport. Killed all four aboard . I think I read it in a recent AOPA magazine. The plane was kept in a hangar but water condensate had accumulated in the tanks.
 
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http://en.wikipedia.org/wiki/Benzene#Health_effects

Benzene increases the risk of cancer and other illnesses. Benzene is a notorious cause of bone marrow failure. Substantial quantities of epidemiologic, clinical, and laboratory data link benzene to aplastic anemia, acute leukemia, and bone marrow abnormalities.[50][51] The specific hematologic malignancies that benzene is associated with include: acute myeloid leukemia (AML), aplastic anemia, myelodysplastic syndrome (MDS), acute lymphoblastic leukemia (ALL), and chronic myeloid leukemia (CML).[52]

The American Petroleum Institute (API) stated in 1948 that "it is generally considered that the only absolutely safe concentration for benzene is zero."[53] The US Department of Health and Human Services (DHHS) classifies benzene as a human carcinogen. Long-term exposure to excessive levels of benzene in the air causes leukemia, a potentially fatal cancer of the blood-forming organs, in susceptible individuals. In particular, Acute myeloid leukemia or acute nonlymphocytic leukemia (AML & ANLL) is not disputed to be caused by benzene.[54] IARC rated benzene as "known to be carcinogenic to humans" (Group 1).

Human exposure to benzene is a global health problem.[vague] Benzene targets liver, kidney, lung, heart and the brain and can cause DNA strand breaks, chromosomal damage, etc. Benzene causes cancer in animals including humans. Benzene has been shown to cause cancer in both sexes of multiple species of laboratory animals exposed via various routes.[55][56]

Some women who inhaled high levels of benzene for many months had irregular menstrual periods and a decrease in the size of their ovaries. Benzene exposure has been linked directly to the neural birth defects spina bifida and anencephaly.[57] Men exposed to high levels of benzene are more likely to have an abnormal amount of chromosomes in their sperm, which impacts fertility and fetal development.[58]
 
http://en.wikipedia.org/wiki/Benzene#Health_effects

Benzene increases the risk of cancer and other illnesses. Benzene is a notorious cause of bone marrow failure. Substantial quantities of epidemiologic, clinical, and laboratory data link benzene to aplastic anemia, acute leukemia, and bone marrow abnormalities.[50][51] The specific hematologic malignancies that benzene is associated with include: acute myeloid leukemia (AML), aplastic anemia, myelodysplastic syndrome (MDS), acute lymphoblastic leukemia (ALL), and chronic myeloid leukemia (CML).[52]

The American Petroleum Institute (API) stated in 1948 that "it is generally considered that the only absolutely safe concentration for benzene is zero."[53] The US Department of Health and Human Services (DHHS) classifies benzene as a human carcinogen. Long-term exposure to excessive levels of benzene in the air causes leukemia, a potentially fatal cancer of the blood-forming organs, in susceptible individuals. In particular, Acute myeloid leukemia or acute nonlymphocytic leukemia (AML & ANLL) is not disputed to be caused by benzene.[54] IARC rated benzene as "known to be carcinogenic to humans" (Group 1).

Human exposure to benzene is a global health problem.[vague] Benzene targets liver, kidney, lung, heart and the brain and can cause DNA strand breaks, chromosomal damage, etc. Benzene causes cancer in animals including humans. Benzene has been shown to cause cancer in both sexes of multiple species of laboratory animals exposed via various routes.[55][56]

Some women who inhaled high levels of benzene for many months had irregular menstrual periods and a decrease in the size of their ovaries. Benzene exposure has been linked directly to the neural birth defects spina bifida and anencephaly.[57] Men exposed to high levels of benzene are more likely to have an abnormal amount of chromosomes in their sperm, which impacts fertility and fetal development.[58]

Then you don't do it, but I had an engine failure and almost went to wires at the end of the runway because I did not sniff the sample.

As a degreed chemist with 30 yrs. experience, I agree that aromatic compounds ( those compounds that contain a benzene ring) are bad players but only with chronic exposure. Two sniffs twice a month is not chronic exposure.
 
Then you don't do it, but I had an engine failure and almost went to wires at the end of the runway because I did not sniff the sample.

As a degreed chemist with 30 yrs. experience, I agree that aromatic compounds ( those compounds that contain a benzene ring) are bad players but only with chronic exposure. Two sniffs twice a month is not chronic exposure.

I agree. I was simply answering the OP :yesnod:
 
I agree. I was simply answering the OP :yesnod:

Sorry, didn't mean to sound bossy but I deal with people that have chemiphobia (my term for the fear of chemicals) on a regular basis and I find it frustrating. There are no bad chemicals, just chemicals that aren't used properly.
 
Things thread brings up a question I have - Is AvGas bad to get on your skin? (I know it's not GOOD per say) I always get a little on my hands when sumping, but last week I doused myself twice in one day [not intentionally] and washed my hands immediately both times, but they still really burnt for nearly an entire day. And even now look super dry a week later with loads of moisturizer. Is this normal? I mean, I'm not intending to continually douse myself but I am curious if I should wear gloves with Avgas? I do for Jet-A because even the smallest amount on my skin burns like h***.
 
if it irritates then by all means protect yourself which may mean barrier gloves - one question though - when you say wash do you mean flush with cold water for ten or fifteen minutes or do you mean thirty seconds with soap and water? don't use soap for flushing chemicals in general...
 
if it irritates then by all means protect yourself which may mean barrier gloves - one question though - when you say wash do you mean flush with cold water for ten or fifteen minutes or do you mean thirty seconds with soap and water? don't use soap for flushing chemicals in general...

I used soap and water, wasn't aware to do otherwise... I apologize if this is common knowledge and a blonde question but why is it better to use cold water on its own than with than soap?
 
soap may help the chemical penetrate deeper in the skin - cold water helps keep the pores closed while copious quantities flushes away the materials - at least thats what we were told to do for lab safety training...
 
soap may help the chemical penetrate deeper in the skin - cold water helps keep the pores closed while copious quantities flushes away the materials - at least thats what we were told to do for lab safety training...

...and digging around a bit more for updated info it looks there are a couple schools of thought, one is flush with soap and water and the other is flush with water...both methods include flushing, not just washing (lather/rinse)
 
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