# Scent article



## Ted Summers (May 14, 2012)

I'm not all that into SAR but I thought this was a pretty cool article 

http://vsrda.org/how-scent-and-airflow-works


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## julie allen (Dec 24, 2010)

This is by far the hardest thing for handlers to understand. It holds true for any detection, not just sar.


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## Sarah Platts (Jan 12, 2010)

Ted Summers said:


> I'm not all that into SAR but I thought this was a pretty cool article


 
That's a good general article for people to begin to get an understanding of scent dynamics but really it's just a scratch of the surface. The reality is it's hard and handlers can spend a lifetime trying to understand it. There are so many variables that can affect it and it's movement. In the mountains, I've heard of dogs throwing alerts for victims that were still several miles away.

And if you work a trailing dog, you are adding another thick layer of scent theory you have to learn on top of this one. For both airscent and trailing handlers scent dymanics is a lifelong learning endeavor.


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## David Winners (Apr 4, 2012)

Sarah Platts said:


> That's a good general article for people to begin to get an understanding of scent dynamics but really it's just a scratch of the surface. The reality is it's hard and handlers can spend a lifetime trying to understand it. There are so many variables that can affect it and it's movement. In the mountains, I've heard of dogs throwing alerts for victims that were still several miles away.
> 
> And if you work a trailing dog, you are adding another thick layer of scent theory you have to learn on top of this one. For both airscent and trailing handlers scent dymanics is a lifelong learning endeavor.


Great points Sarah. I agree that this is just the tip of the iceberg. I find it very educational to always discuss airflow and scent dynamics after every find or miss. It's beneficial to have multiple dogs running the same venue to give a better understanding of what is going on. It's also interesting to me to begin training events before sunrise and then continue into the heat of the day to showcase the change that occurs as the energy of the sun is added to the scenario.

My goal as a handler is to get the dog into the most productive areas, in the most efficient manner possible. We can strive towards this goal by better understanding of airflow and scent theory. I have a lot to learn yet. Some finds are still like magic to me.

David Winners


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## Sarah Platts (Jan 12, 2010)

David Winners said:


> My goal as a handler is to get the dog into the most productive areas, in the most efficient manner possible. We can strive towards this goal by better understanding of airflow and scent theory. I have a lot to learn yet. Some finds are still like magic to me.
> 
> David Winners


Just beware over thinking it. I was working with new BH handler. She was making the transition from working an airscent dog to a trailing dog. After she scented the dog, instead of letting the dog work the trail, she started dragging the dog from place to place. When I asked her why she was doing this she said she was taking the dog to places where the odor should be and when she felt the dog was in scent she would then drag the dog down the street to the next place she felt odor would catch. When I asked her how she knew where the odor would be she stated that since she was the human and could think that she knew more of where the odor should be and she was taking the dog to those locations. We got into a bit of an intense discussion (aka argument) and finally told her to put the dog up because it wasn't needed. We were going to just throw a harness on her and let her findl the missing subject. 

It took having her watch other handlers working and "letting go" of the dog before she started understanding the diffs between airscent and trailing. Unfortunately, I don't think she will ever change her mindset and that will keep her from being successful with her hound.


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## Nancy Jocoy (Apr 19, 2006)

I think they just redid all the slides that have been out there since Sytrotouk's illustrations, though I must admit what they are calling thermocline I have always heard called a chimney effect and, since I work a good bit on water cadaver (Beau already has two successful water searches and Grim had several), there is debate about just how much odor really is or is not stopped by a thermocline. 

The slides look good though.. 

For HR you have to add an underground dimension as well as odor can seep in and flow underground and come out elsewhere.

Good references (old) are Fire Weather (an out of print handbook) and some of Hatch Graham's work.

Chris Weeks did a good demo for us for trailing and air scent dogs by walking along with flour and throwing handfuls in the air to help folks visualize odor (and who has not played with smoke bombs?). What was falling on the path or to the side on the ground and vegetation was what the trailing dog was typically working and the lighter particles carried on the wind what the air scent dog was typically working though both can cross over to some extent.


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## David Winners (Apr 4, 2012)

Sarah Platts said:


> Just beware over thinking it. I was working with new BH handler. She was making the transition from working an airscent dog to a trailing dog. After she scented the dog, instead of letting the dog work the trail, she started dragging the dog from place to place. When I asked her why she was doing this she said she was taking the dog to places where the odor should be and when she felt the dog was in scent she would then drag the dog down the street to the next place she felt odor would catch. When I asked her how she knew where the odor would be she stated that since she was the human and could think that she knew more of where the odor should be and she was taking the dog to those locations. We got into a bit of an intense discussion (aka argument) and finally told her to put the dog up because it wasn't needed. We were going to just throw a harness on her and let her findl the missing subject.
> 
> It took having her watch other handlers working and "letting go" of the dog before she started understanding the diffs between airscent and trailing. Unfortunately, I don't think she will ever change her mindset and that will keep her from being successful with her hound.


LOL... wish I would have seen that. You should have harnessed her up 

I'm just quality control. I let my dog satisfy it's curiosity, and when it looks to me, send it where I would like to see it search. I'm always looking for those productive areas, but I'm fully aware of how much better at finding bombs my dog is than me. 

David Winners


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## Sarah Platts (Jan 12, 2010)

Nancy Jocoy said:


> For HR you have to add an underground dimension as well as odor can seep in and flow underground and come out elsewhere.


And if in water, hydrology mechanics and science comes in to play along with scent dynamics.

I think, for me, thermoclines come more into play when you have separate flows of fresh and salt water coming together (I'm not talking of brackish water). These seem to resist mingling initially and depending the water type the body is suspended in, could maybe affect location of alerts (?). If anyone has worked those let me know how it went for you.


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## Nancy Jocoy (Apr 19, 2006)

One thing that really impressed me (and I have not verified) was that the dog's 3D "vision" through its nose is probably more sensitive and complex than our vision through our eyes.

That was based on the number and complexity of the receptors as well as the amount of dedicated brain space to process the information.

A lot of why we are such good hunting partners is we live in two different worlds with combined senses better than either one of us has alone.


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## Jim Delbridge (Jan 27, 2010)

Very simplistic demo. Would be good to show a middle-school class, but would confuse more handlers than help me thinks. The chimney effect will screw them up for sure as it suggests the evergreens pull the scent up the outside rather than the inside. Chimney effect on leafy trees tends to flow up the dark bark when the sun is shining on it and flows down the dark bark on the shady side.

Probably my biggest problem with it is I think the skin raft theory is a bunch of hooey. Over the years I've run experiments where I literally nearly strip and physically try to slough off skin rafts in a gully as I traverse it up to a knoll. Then on the knoll I wrap myself up completely with only the mouth exposed....helps to do this in winter with snow. Then I proceed to blow my breath out over the gully watching my breath move out over the gully to the other side. On many occasions I've observed the dogs go down into the gully (on my trail/track) and lose my scent. They go back up to the opposite side and pick up my outgassing downwind. 
I believe Syrotuck explained his observations with what he imagined was "skin rafts" and then the handler community made it their religion.

Now, the real fun can come about for HRD handlers if they can understand the environment such that they place a source in plain sight such that there is no scent emanating from it, but the poor handler can see it and the dog possibly walks over it multiple times (credit goes to the dog that isn't visual, but a nice plastic bone can fix that as well).

Consider a situation where the source is placed on an insulator such as dead tree bark. The ground is warmer than the air such that scent is pushed down. If you want the dog to solve it, put this near a downward slope such that the scent can wash down the slope and then rise up slightly from the warmer ground temperature. Then the dog can pick up scent below and work up to source. It's all thermodynamics. 

Oh, a good course to learn flows is fluid hydraulics. I took this oh so long ago (...ack...some 32 years ago).

Nancy, I know exactly what you mean by three-dimensional scenting. I first saw this in my first dog working a "vanished" cemetery on an Oklahoma plain with 30 mph winds. I noticed she was turning her head and working with the wind like we would turn our heads to locate where a sound is coming from. The historian I was working with asked me how I taught her to do that. I could have BS'd, but commented that I was amazed as she was. Over the years, I've noted every one of my dogs doing it on detailed surface and buried. Both dogs demonstrated it this morning when I had them working teeth in a gravel road.


Jim


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## Nancy Jocoy (Apr 19, 2006)

I just looked it up and Syrotuk died in 1976 (I think it was a heart attack). He was a young man, 41 but sure gave a lot of good foundational info to SAR.

But our knowledge has improved though I am not sure we really have a clear understanding of exactly how dogs do what they do though we do understand more how the nose works, how scent flows through it under different sniffing methods etc. and it is fascinating. They are walking about with something better than a Gas Chromatograph in that snout.

I do think Hatch-Graham is definitely a worthwhile read and I saved a lot of that stuff to my hard drive as it is going away though there is no way I would actually USE his POD calculation because the interaction of weather and terrain is much more complex and we are part of the POD too...more of a gut feeling / experience kind of thing....A lot of that...We pretty much only have straight line wind if a front is coming through. Our prevailing wind is "variable". I have definitely seen a lot of real life examples of lofting though. And had the dog run right over a hide in plain sight.


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## Sarah Platts (Jan 12, 2010)

Nancy Jocoy said:


> I just looked it up and Syrotuk died in 1976 (I think it was a heart attack). He was a young man, 41 but sure gave a lot of good foundational info to SAR.
> 
> But our knowledge has improved though I am not sure we really have a clear understanding of exactly how dogs do what they do though we do understand more how the nose works, how scent flows through it under different sniffing methods etc. and it is fascinating. They are walking about with something better than a Gas Chromatograph in that snout.


Syrotuk was an early groundbreaker with his work and certainly has earned his place in the SAR annals but things have progressed so far from his time. We now understand the structure of the nose better, airflow changes, nasal scent repositories, and their sensitivity to odor. Even what we think are the components of human odor is changing as the number climbs past 450 identified compounds, chemicals, and whatnot. All I know is that there's more to scent than a bunch of skin rafts. I've trailed guys wearing full body clean suits and wetsuits (which one would think would lessen or prevent the dispersion of skin rafts) and the dogs did just fine. So skin rafts *might* be part of the scent picture but I don't think its the whole one and may only be a very small part of what the dog uses to follow or find you. 

P.S. For the hunter dudes, those Scent-Lok and charcoal suits didn't stop the dogs either.


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## Craig Snyder (May 7, 2012)

Sarah Platts said:


> P.S. For the hunter dudes, those Scent-Lok and charcoal suits didn't stop the dogs either.


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## Bob Scott (Mar 30, 2006)

"P.S. For the hunter dudes, those Scent-Lok and charcoal suits didn't stop the dogs either."

Biggest con on the planet! 
It's amazing how our ancestors survived without all the new fangled crap. :roll:


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