Allegheny Mountain Rescue Group

Pocket Graham Tables

Hatch Graham's Dog POD Charts in a pocket-sized reference card

Download the POD Charts in zip format.


Formatted by Ken Chiacchia

Disclaimer:  These cards are intended as a training aid only.  Their use or misuse, especially in actual SAR operations, are not the responsibility of Ken Chiacchia or Allegheny Mountain Rescue Group, its members and parent organizations.  Note that Ken Chiacchia and AMRG retain copyright to this format of the tables only to prevent its misuse. 

How to make and use the cards:  First, read Hatch Graham's article, "Probability of Detection for Search Dogs or How Long is Your Shadow?"  You need to understand the concepts in this article and a little about how Hatch generated the data to use the cards properly. 

Second, consider that Hatch's numbers -- partly measured, partly calculated; partly observed, partly theoretical -- were intended as a first step toward understanding how weather affects dogs' ability to find people using their noses.  This work was never intended as an end-all, and no one should accept the numbers contained as valid for every dog, in every environment, on any particular day.  Use the cards to better understand your dog's performance in the places you usually search; they're especially useful for beginning dog handlers, to help them internalize realistic PODs rather than "wing it." 

Third, use a color printer to print out the PDF file accompanying this "readme" file.  Print it two-sided, so that the big atmospheric stability matrix prints four times on one side of the sheet, and the smaller wind class and POD tables print on the other side.  While you can print out a nice reference card in black & white, the color coding of search types will only show up, of course, if you use a color printer. 

Before you do anything else, examine the tables:  are there terms you don't recognize or don't understand?  If so, return to step one -- or you may need to go earlier, to any of a number of good basic training sources in search and rescue.  NASAR's FUNSAR class isn't the only good class -- there are many that have a claim to being at least as good -- but it has the undeniable virtue of wide accessibility. 

Finally, cut the resulting sheet on the dashed lines that say "cut."  You should have four reference cards now.  At this point I recommend trimming the cards (careful you don't cut off part of any of the tables on the opposite side as you trim) and laminating them to give them a little weatherproofing and durability.  Next fold the laminated cards on the remaining dashed lines (they say "fold," unless you cut off that word trimming the cards).  If you like, you can also punch a hole in the plastic so that you can string the card together with your compass, whistle, and grid reader; you can also use a small piece of stick-on Velcro to keep the folded card closed when you aren't using it. 

You now have a pocket-sized, reasonably weather-resistant version of Hatch Graham's tables you can use as a field reference when training with your dog.  Go now and use them wisely, as the Hatch intended.