Code of Practice

There are no specific regulations for timing a Head race (see Regulations). This is an unofficial code of practice drawn from other sports and from practical experience, together with a commentary.

Head Race Timekeepers Code of Practice (Unofficial)

  1. Definitions
    1. A Time is the time of day, or time elapsed since a known time of day, when a competitor passes a line across the course.
    2. The Start and Finish are lines across the course that competitors pass to start or finish the race.
    3. A Result is the amount of time taken by a competitor to progress from the Start to the Finish.
    4. A Timing Device is a device used to assign a Time to a competitor when they pass a line across the course.
    5. A Timer is the person or equipment registering the moment when a competitor passes a line across the course.
    6. A Timing Method is a procedure used to obtain a Result.
    7. A Timing System is a combination of Timing Device and Timing Method.
  2. The Course
    1. The Start and Finish must each be identified by a post on both sides of the course.
    2. The Start and Finish should be perpendicular to the course. Where they are materially not perpendicular, competitors should be informed of the fact.
    3. The posts should create a clear line that crosses the entirety of the course from the point of view of the Timer.
    4. All Timers should be in line with the two posts marking the Start or Finish.
  3. Timing System
    1. Results should not be recorded with a resolution that exceeds the accuracy of the Timing System over the duration of the race.
    2. Times for different competitors may not be obtained from different Timing Devices, different Timers, or different Timing Systems. In the event that a primary Timing System fails, then Results for all competitors must be taken from a backup system. If an individual Time is missing from a primary Timing System, then a Time from a backup system may be inserted only by adjusting for the average difference in times over a number of adjacent competitors.
  4. Timing Devices
    1. Timing Devices must have a certificate of accuracy from a recognized national calibration laboratory.
    2. Times may not be taken from an automated Timer (e.g. video or photo finish) unless the timing is taken from a certified Timing Device.
    3. Timing Devices at Start and Finish should be synchronised before the start of the event to a common reference time source. Once synchronised, individual Timing Devices may not be re-synchronised during the race. However the Timing System as a whole may be re-synchronised if necessary.
    4. Results may not be used for the purposes of records unless the Start and Finish Timing Devices can be shown to be synchronised to within the level of accuracy used for the Result.
  5. Timer
    1. The Timer should be able to demonstrate a level of consistency of Times taken.
    2. The Result should be recorded to the level of consistency of the Timer. For example, if a Result is given to one tenth of a second, then the Timer should be able to demonstrate consistency of timing to one tenth or better.
  6. Timing Method
    1. A defined Timing Method should be followed to determine when a competitor crosses the Start or Finish, and to assign the Time to a competitor.

Commentary

The Start and Finish need to be clearly marked for the timers. A mark only on the far side from where the timers are placed is not sufficient, as it leaves material variation in where the timer considers a boat to have crossed the line.

It is not acceptable to mix times from different systems or timers and keep the same level of accuracy. For example, if a stopwatch is used, it is not acceptable to take most times from one watch, and take missing times from another. In this case, the times of one timer may legitimately be one tenth or more different from another. Instead an average of times must be calculated, and the average difference between timers applied to the missing time.

Likewise, if a hand-timing system is used, it is not acceptable to take a missing time from a video. In this case the video will not have the reaction time of the hand-timer. Instead: either an average of times must be calculated; or the video could be used to establish the gap between adjacent competitors and the gap applied to the hand times.

A regular stopwatch can be used for timing, although it should be certified by a calibration laboratory. Stopwatches are generally used to time quite short intervals and it should not be assumed they are accurate over longer periods.

If a stopwatch system is used, then as a guideline times should generally be given to the full second, and not tenths of a second.

Although a video camera can show time to the frame, it should also not be assumed that the time is accurate. To give accurate time a video camera needs to be locked to an external timing device, or time derived in a different way.

Timing devices will generally be synchronised before the start of the race. There are several different components of accuracy in synchronisation:

  • the accuracy of the external time source
  • the accuracy of the method of synchronising to the time source
  • the accuracy of the method of synchronising between timing devices.

For example, two timing devices for Start and Finish will typically be synchronised before the start of the race. It makes no difference to the accuracy of results whether they are synchronised to GPS or a sun dial. The elapsed times of competitors will be the same.

If two timing devices are synchronised by hand by separate timers, and so have slightly different times, it will make a difference to the absolute elapsed time but not to the relative time between competitors, and so not to the placings.

If two timing devices are synchronised at different times, and even from different sources, then it will still not make a difference to placings, but the times should not be used for records since the absolute elapsed time will not be accurate.

Mostly the timing devices are synchronised at the same time so that times from different devices can be mixed, but this is not legitimate for hand timing because of the difference in accuracy of different timers.

If a timing device is synchronised to GPS, then if necessary it could be legitimate to re-synchronise it to GPS during the event, because all times will still be within the overall accuracy of the device. However if a device is synchonised to a wall clock, then it would not be legitimate to re-synchronise it during the event to a mobile phone, because the difference in time between the wall clock and the phone is not precisely known.

The ALGE-Timing device can be synchronised to GPS. Therefore it will be legitimate to re-synchronise a device during the event. For example, if two divisions are running in morning and afternoon, then it would be possible to re-synchronise the devices from two separate GPS units without returning to base.

The main difficulty in timing a Head race manually is to make sure that a time is assigned to the correct competitor. Obviously in a small event, or for a single competitor, or at the Start, this is easy. The difficulty arises when several competitors cross the finish line close together, and especially if they have lost their boat number.

The list of boats and the list of times are two independent data streams, and it is vital to synchronise them together. For example, if there are six times and six boats, then we can assume that each time is assigned to a boat in the order in which they finished. But if we have six times and seven boats, or seven boats and six times, then we cannot be sure of which time to assign to any of the boats. In the worst case the error could continue with each subsequent boat and time being out of sync.

The best way to deal with this is to match specific boats to times as often as possible. Then, if there is a mis-match, it can only lie between matched boats.