I want to share a recent experience with someone using a 3-year-old calibration course I set up for one-time use to measure an out-of-town 5km course route.
On May 13th, I received a phone call from a measurer telling me he broke a 100-foot tape while setting up a calibration course. The measurer asked if I knew of any existing calibration courses nearby that he could use. Wanting to help, I directed him to a calibration course of mine about 15 miles away. After being unable to procure a second 100-foot tape, the measurer decided to call it a day and go home rather than calibrating at the nearby course.
On June 17th, I received another email from the measurer asking if the calibration course I suggested on 5/13 was marked with PK Nails. I informed him that I mark all calibration course endpoints with PK Nails and spray paint, as is standard. The following day at 8PM, he called to tell me that something was wrong with my calibration course. He said that my calibration course was 30 counts (approx. 10 feet) longer than his. He discovered this apparent “discrepancy” after calibrating on his home course, then driving 70 miles to calibrate at my course. It is unclear why he felt he needed to calibrate twice. He then measured the 5km re-certification once and drove 70 miles back to his home calibration course to recalibrate a 3rd time.
Naturally, I asked him if he found and verified the calibration course endpoints. He responded that he did not verify the endpoints to the landmarks indicated on the map, and the paint marks had faded away. Additionally, temperatures had been decreasing since 6pm that evening, so depending on what time he calibrated, his tires may have influenced his recorded counts.
Given these factors, I consider this a typical result of using someone else’s calibration course without doing at least one taped measurement to verify the distance. In performing validations, I often locate poorly mapped and marked calibration courses then remeasure to establish or verify the distance. I certainly do not claim to be infallible, but I disagree with this discrepancy due to the number of uncontrolled variables and lack of verifiable endpoint data.
While talking to the measurer, he told me his home calibration course had been remeasured at least three times to account for various changes over the years. While this is commendable, most calibration courses are not customarily remarked, at least not at regular intervals. Coordination with the original measurer is the best way to reconstruct old, seldom-used calibration courses.
The calibration course location map is only a resource when a calibration course has been well-documented and maintained. How many calibration courses on the location map truly meet these requirements? The benefits of a nearby, one-time use calibration course are many, far outweighing the bother to measure them.