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16 replies

Detailed Description of Start/Finish & Turnaround POINTS

nathanporchnathanporchMember
I would like to take a moment to stress the importance of detailed descriptions of Start/Finish & Turnaround POINTS. I stress the word POINT to, well, to make a point. When we are recording a measurement to detail one of these POINTS, it's important to remember that we are not recording the location of the Start LINE. We are recording the location of a POINT from which the Start LINE will extend. Many times I will place my PK nail and I'll add a second (unmeasured) nail on the opposite side of the road/trail etc. that would allow for a chalk line to be snapped to establish the Start LINE. In the case of a Turnaround, we are recording the specific POINT that runners will travel the SPR around.

I see many Start/Finish & TA's with descriptions that are written in the same way as uncertified mile/km markers are recorded. By that I mean that they are generally written with the least amount of wording, whole number measurements and generally from a single fixed point. All fine for uncertified mile/km marks. Not fine for certified S/F & TA points.

When preparing a map or working with someone who is preparing one, I like to reiterate that the entire reason for the map is so that someone who has absolutely no familiarity with the course or even the geographical area, can reference the map and have runners follow the same course as the measurer.

When recording Start/Finish points, recordings should be made from two fixed objects. The measurement should be recorded to the fraction of inch. In the event that your marker nail has been removed or was not able to be placed, any person wanting to find the correct POINT would simply pull a measuring tape from the fixed object out to the distance that you've defined. They would then trace a semi-circle of that distance and repeat the process with the second measurement. The point where those two semi-circles intersect is your fixed point. Providing only a single measurement only provides half of the needed information as the measured point could be anywhere along that semi-circle.

Additionally, your description of these points should include any other information that would help someone find the POINT. So a good description of a start point could sound something like, "On Frederick Street travelling West in the area that is at the Southwest corner of the town pool, 17'2 3/4" North of telephone pole# 125748, 5'6 1/2" East of the center of the manhole cover marked CECIL COUNTY WATER DEPARTMENT (manhole cover is 3' in diameter)" The point here is, the more info the better.

All of the same applies for the turnaround point as well. Turnaround points though must specify whether runners should travel around the point in a clockwise or counter-clockwise direction.

Jim Gerwick inquired in a previous thread if adequate descriptions of these points where noted, if it was necessary to include a detailed inset map. I would say that if space was limited and the descriptions were adequately detailed then the inset could be kept out. But before deciding to leave it out, one should take a step back and assume the role of someone who just arrived from Mars and really evaluate if they are providing enough information.

Our maps truly are the representation of our work. While some measurers may possess better computer savvy and others artistic ability to draw impressive maps, we should all have the ability to provide detailed information for future event planners to work from.

Happy measuring!
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duanerussellduanerussellMeasurer
Nathan, I will offer a counterpoint.

When we measure using SPR, normally one curb or the other is inline with the SPR. If there is a light pole on the same curb, I can measure 3' from the nearest edge of the light pole, and state that the Start is "3' east of east edge of light pole 123". From that point, the line can be extended.

We use SCPF, which introduces imprecision into our descriptions. To describe with the precision of 17' 2½" is unnecessary. The SCPF makes precision of units less than a foot irrelevant. And, while I set out many courses, I don't carry a tape measure with me. If you tell me 17' 2½", or 17', or 18', I will pace it off, and get pretty darn close. I will then find your mark. If your mark is gone, I will pace it off twice, and then call it good. Might I be a foot or two off? Sure. But, you use the SCPF when you measured, so I don't know if you were 5 meters or .1 meter off on the overall length when you determined where the endpoint is located.

Turnaround points are handled the same. If I am heading east on a street, then have a turnaround, it doesn't matter if my point is located on the north curb, south curb, or the middle of the street. It will always be described as 3' west of (a) light pole. There is not enough difference in the length of the course to care if they place the turnaround in the north lane, south lane, or center of the street. The turnaround it anywhere along the line extending from my described location.

If one makes the turnaround with a set-radius semi-circle, then the centerpoint of the arc can also be described as being anywhere along a line extending from a described point.

My opinion is that, since we use the SCPF, to write descriptions to less than a foot (or 30 cm) is projecting a sense of precision that we don't deliver. Your measurement today worked out to your described point. However, if you did your measurements again tomorrow, you would not hit the same point. You may be within a foot, but you would not be within the quarter-inch you used in your description.

Both of us will have supporters, and both will have objectors. I feel my take reflects the realities of our measurement technique, and that saying a Start, Finish, or Turnaround is east of a pole is fine. 3 feet east of the pole is 3 feet east of the pole, no matter where on the street one cares to stand. If a particular situation requires a different description, so be it. Each course may have some situation that is unique to it, but most will fall into the "general situation" bucket.

Describe how you like, but I will continue to encourage "to the foot", and complete-but-succinct, descriptions.
jimgerweckjimgerweckMember
As they said in The Wizard of Oz, people do go both ways, and there's validity in what both Nathan and Duane say.
I had never thought of what Duane stated that the riding technique isn't precise enough to merit measurements of less than a foot. OTOH I question whether we can or should measure to fractions of an inch - I suppose it's useful, but as Duane says, perhaps deceiving.
As to S/F details, I'll continue to put them on my maps, even though I find they take the greatest amount of time in the entire process. Having seen utility poles and houses re numbered and roads renamed a schematic gives an additional and perhaps more permanent way of locating critical points.
oscarwagneroscarwagnerMember
Describing distance determining points can take a lot of time as well as precious space on a map. One technique s to make the course a little long to put the S & F at natural permanent objects like the end of a traffic island or telephone pole. That way, you don't have to do an inset with lines, numbers and arrows. Race directors are not generally technically oriented so you also greatly improve the odds of compliance by making distance determining points simple and obvious.

Oscar
nathanporchnathanporchMember
Duane makes an excellent point regarding SCPF and how conditions on any given day will result in variations of a minute measurement.

I guess my thinking is to provide the precise measurement during the time of measurement demonstrating the accuracy on that given day. If a RD wants to pace off the distance and call it "good enough" I'm ok with that and realize that there shouldn't be any problems if the need for validation arises.

Thanks for your input Duane
AdminAdminMember
About a year ago there was a long discussion about how much too long a course could be and still be certified at the standard distance. For example, if a course ends up being measured at 5003 meters can it just be certified as a 5k? The final decision was that a course must be certified at the distance it was measured, so in the previous example the course must be certified at 5003 meters, not 5k.

So moving the start or finish line to be even with a landmark isn't really permitted anymore if you know it makes the course a couple meters longer than the 5000m the original course was measured at.

"At least as long as advertised" is no longer the standard.
B bobthurstonMember
Mark,

I still have a problem with this statement. I'll sum it up this way: do you, or any measurer, really know that a course is 3 meters longer than 5,000 meters? We put in a SCPF ("extra" 5 meters) in part because we CAN'T really know the length of a course to the nearest meter. Another measurement, possibly by another measurer on a different bike on a different day, might find the course to be a good bit shorter than the results we obtain. If we choose to state that the course length is 5003 meters, that statement implies an accuracy we don't have.

If we did have that kind of accuracy, why not state that the course is 5008 meters in length (to account for the SCPF)?

I still think our standard is that the course not be short. "At least as long as advertised" may not be exactly what we want to say, but I think it's better than stating that the course is 5003 meters.

Judgement must be used with all of this. If a course is, say, 10 meters longer than it needs to be, I have no problem with stating its length as 5.01 km, for example (and I have done).

And I would endorse Oscar's comment about natural landmarks for key points. It's better to add a few feet in order to get to a point that an RD can find easily, than to have the course screwed up because someone measured 2.5 feet to the east instead of the west-- for example.
justinkuojustinkuoCertifier
I am not suggesting any changes in our policy to display the course distance as the original measured intended (with the implied plus or minus 1-meter accuracy.) But, if we were to be scientific, perhaps the course distances should be displayed using significant digits.

https://en.wikipedia.org/wiki/Significant_figures

The standard marathon distance, as displayed on the certificate, might change from 42.195 kilometers to 42.2 and the 5000 meter distance might change to 5.00 kilometers. A distance that was measured as 5003 meters might be displayed as 5.00 kilometers.
AdminAdminMember
Bob and Justin,

I don't disagree with either of you, or with Oscar's idea of moving the start and/or finish to line up with landmarks. But we can't say that courses must be certified at exactly the distance at which they were measured, and at the same time say it's okay to lengthen the course a couple meters by moving the start line from its original measured location.

Either there's an allowable tolerance or there is not.
J jhpMember
There is no argument that the Start, Finish and Turnaround need to have detailed and explicit descriptions. IMO however, a single point is sufficient if the start or finish line is perpendicular to the curb or if it is taken from the SPR. The good runners are smart enough to line up on the side of the SPR.
As for within a foot, I always tape my Start, Finish and Turnaround, so there is no reason to throw away that accuracy by rounding off. In the big scheme of things it might not make any difference, but if we are in the business of accuracy there is no reason not to use a taped measurement to the inch.
pastmemberpastmemberMember
Good discussion brought up by Nathan here, IMO.
I think Bob Thurston nails it in his interpretation. There is both physical science and human science in the final equation that determines how we identify and record timing points. I think Justin has a point with his "significant digits" recommendation. I would love to see a 5K road course certified, then validated, and then finally steel tape measured as an experiment which could throw some light on the topic. Note: I am not volunteering to do the steel tape measurement at this time!
B bobthurstonMember
It's important to distinguish between accuracy and precision in all of this. We can only discuss accuracy in the context of the measurement methods we are using.

Let's say you are very good at pacing off distances. You may be able to measure something this way to the nearest foot, as in "this street is 23 feet wide". But it would be foolish to try to state that distance to the nearest inch (unless maybe you are Pete Riegel who won the measurers' challenge so many times!).

If I state that a course is 5001 meters long, that implies that it's closer to 5001 than to 5000 or 5002. Really? I don't think we can be that confident of any bicycle-measured course. Another measurer could come along, use good measuring techniques and declare that it is 4996 or 5003. We don't really know which is right, at least not without a lot more trials. (This is why we have the SCPF).

Actually I don't think we are stating that our courses are "exactly" (whatever we mean by that) 5 km or 42.195 km or whatever it is-- we are stating that the course is at least the stated distance.

There is no harm in specifying a key location to the nearest inch, but using whole feet should be ok too. A precise distance (like nearest cm or fraction of an inch IS important if you have placed a nail that you want people to find.
AdminAdminMember
I mostly agree with you Bob, except where you say that we are stating that the course is at least the stated distance. That is no longer the standard.
It has been decided (correctly I believe) that we should certify courses at their actual measured distance. So we should not certify a course to be 5k if its measurement came out to be 5030 meters, for example.
B bobthurstonMember
I agree with the 5030 point. Our measurement methods are robust enough to justify "5030" as a course distance.

I would question "5003" as a distance; I think we'd be better off calling that one 5 km or 5,000 meters.

How to distinguish between those situations? We've discussed this a number of times, and I'm not convinced there is a "right answer."
genenewmangenenewmanRRTC Chairman
Well, our measurements are not precise. Hence, we agreed if one submits a course that records a 5k to be 5003 meters, then that's what is the recorded distance.

I understand that the 3 meters is no big deal, but where do we draw the line for any measurement. Do we say if it is more than a certain percent, then that is recorded?
duanerussellduanerussellMeasurer
Bingo, Gene. Using our methods, we endeavor to make a 5k course 5,000 meters in length (using SCPF), whether by using a spur, or moving one of the endpoints. If, however, we are asked to measure the course between set points, and it measures to 5,003 meters, that is the length to be certified. No discussion as to what it might be if measured with chains or steel tape. It measured to 5,003 meters using our measurement process. It did not measure to 5,000 meters.
pastmemberpastmemberMember
Makes sense to me, Duane. So, to attempt an answer to Bob's question, what about 1/10th of 1%? That is, if a "5K" is measured at 5005 meters, we are OK calling this a "5K". If it measures as 5006 meters or more, we do not allow the "5K" term.

Again, I refer to one course I know of where U.S. records have been set that upon validation proved to be well beyond 1/10th of 1% long. I suspect there may be others in this category. Obviously, we are not just measuring to say "the distance is at least ____". This makes no sense.

I feel our measurements, if not precise, as Gene says, are "accurate" enough that they should never exceed 1/10th of 1%.

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