As you know, USMS passed a rule that will require us to measure any pool in which we hold a meet, IF we want the times from that meet to count for USMS Top Ten. I'm trying to figure out the best way to do this - what sort of tape to buy, the best method to use, etc. (Can you tell that I'm an engineer?)
I'd like to hear from those of you who have measured pools. What brand of tape do you recommend? What length? (60 meters?) Any idea where I can buy such a tape? Any suggestions for how to get a good (accurate) measurement, especially over a 50 meter course?
FYI, below are the instructions on how to perform pool measurements, taken from the USMS Pool Length Certification Form.
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"A completed form must be on file or submitted with an application for sanction or recognition to your LMSC Sanctions Chairman. For pools utilizing bulkheads, completed forms from each session must be included with results sent to the Top Ten Chairman if the results are to be included in Top Ten submissions.
Measurement procedures:
--Measurements must be conducted using a measuring device with the minimum measuring quality of at least ± 0.005 m (±.0.20 inches or 0.016 feet) over the nominal distance. A laser based measuring device may be used but it must be as accurate as required for steel tapes. Tapes may not be combined to perform the measurements.
--Measurements may be reported in either the English system (feet/inches) or the metric system (meters/centimeters).
Instructions for pool length measurements:
--Measurements must be conducted for each lane. Inspect each end of the pool to insure that it is vertical. If there are any protrusions from the wall into the pool between 0.8 meters (2.5 feet) below the surface to the top of the touch pad or wall or up to 0.3 meters above the surface whichever is higher, you must use the protrusion as your measurement point. Otherwise, measurements must be taken in the center of each lane at water level.
--The measuring device shall be moved up/down and left/right at least 12 inches (unless you are on a protrusion) during each measurement and the minimum distance for each measurement recorded.
--Measurements may be conducted with or without touchpads in place. However, if touchpads are used the pool must still meet the length requirements with them in place.
--Permanent courses need only be measured once unless structural changes have occurred since original measurement.
--For pools with a moveable bulkhead, after each session a course measurement must be confirmed by a responsible person. Only the outside lanes and a single center lane need to be measured to confirm the integrity of the bulkhead and its placement."
I have a couple of concerns here.
When measuring the pool, one has to allow for touch pads (as stated in the instructions). If you never plan to have touch pads, there is no problem. If you are going to have touch pads, then you either take your measurement with the touch pads in, or you allow for them in your calculation. For long course pools, sometimes touch pads are put in both ends of the pool. ( I would also suggest that this is also important with pools that have bulkheads). If you are fortunate enough to have supervised students from an engineering class, they may forget to take that into consideration.
There are handheld laser devices available, priced around $500, that can measure over these distances with accuracy to the millimeter.
Mary, would you let us know where these devices can be purchased, in the past we have seen laser measuring devices with this accuracy costing more than $5,000. Electonic pricing is always coming down, so devices this accurate may be available. If they are, I think we would like to purchase one.
If any measurement is very close, ie about 50.03 meters, and the measurement is made with a metal tape, remember that the tape was probabily calibrated to a measurement made at 20 Deg C. If the temperature is warmer (or cooler), you may have to calculate the length after including the co-efficient of expansion.
michael
I have a couple of concerns here.
When measuring the pool, one has to allow for touch pads (as stated in the instructions). If you never plan to have touch pads, there is no problem. If you are going to have touch pads, then you either take your measurement with the touch pads in, or you allow for them in your calculation. For long course pools, sometimes touch pads are put in both ends of the pool. ( I would also suggest that this is also important with pools that have bulkheads). If you are fortunate enough to have supervised students from an engineering class, they may forget to take that into consideration.
There are handheld laser devices available, priced around $500, that can measure over these distances with accuracy to the millimeter.
Mary, would you let us know where these devices can be purchased, in the past we have seen laser measuring devices with this accuracy costing more than $5,000. Electonic pricing is always coming down, so devices this accurate may be available. If they are, I think we would like to purchase one.
If any measurement is very close, ie about 50.03 meters, and the measurement is made with a metal tape, remember that the tape was probabily calibrated to a measurement made at 20 Deg C. If the temperature is warmer (or cooler), you may have to calculate the length after including the co-efficient of expansion.
michael
