This article from John was published in the Oct 2009 edition of O-Know.  Although a well discussed topic I thought it worth including to reinforce the importance of this issue.


In both qualifying heats for the World Masters long distance event, complaints were lodged with the organisers regarding some controls which were placed very close to each other.  One went to a protest but that was dismissed on technical grounds.  Two top Australian women competitors made mistakes by punching the wrong controls.  As a result they could only then compete unofficially in their remaining final races.  I must emphasise that it is the runners responsibility to check the control numbers, but in the heat of big races that can be overlooked or maybe misread.  That is an understandable explanation – but is not an excuse.

Editors note:  the following is the current IOF rule 19.4 replacing John's wording.

Controls (including the start control flag) must not be sited within 30 metres of each other. For Sprint, this may be reduced as follows. For map scales 1:4000 or 1:3000, the minimum running distance between controls is 25 metres and the minimum straight line distance is 15 metres. (See also Appendix 2, #3.5.5). 

When the control features are similar (not distinctly different in the terrain and/or not distinctly different on the map), the minimum straight line distance between controls is 60 metres (30 metres for map scales 1:4000 or 1:3000).

A crucial factor here is the interpretation of what is meant by “distinctly different”.  There may well be a tendency for course planners and controllers to accept that if two close features are different on the map then that permits them to be both used as control sites.  Further, if the features can be described differently (i.e. on the control sheet), then that is sufficient to distinguish them. However, David Rosen, Chair of the IOF Rules Commissions, in his recent advice to IOF Event Advisors (regarding the change to sprint events) says:  “…the aim should be to test the navigational skills of competitors and not to trick them.  Note that if the features might appear similar to the competitor, then the minimum separation is 30m [or 60m for non-sprint maps].  For example one control might be described as tree and another as fence, but if the tree is right next to a fence then the controls might well seem similar to a runner.”  Thus he is suggesting that the crucial test of difference between control features is whether the runner will see them as different, and not necessarily whether they are different on the map or can be described differently.  This is a really important point for planners and controllers to take on board with their events.

Lets look at the examples from the WMOC qualifying heats:

 Qualifying Race 1

Close controls 1

The confusion here was between controls 100 and 141.  100 was described as the watercourse end; 141 as the watercourse junction.  They are both part of the same watercourse and there is a scattering of small thickets around them (the black dots and areas).  The circles are touching indicating that the controls are slightly less than 60m apart. 

The features are described differently, but there is a possibility that a runner might see them as similar.  Maybe it would have been less confusing if the termite mound (brown cross) in the 141 circle had been used instead.

 Qualifying Race 2

Close controls 2

Here the confusion was between a control placed at the SE foot of the earth bank alongside an eroded watercourse, and in the small gully in another part of the watercourse erosion system.  On the map the features are about 4 mm apart – i.e. 40 metres.  That’s OK if they are distinctively different – but might the runner see them as similar? 

This section of the map is predominantly yellow (open paddock) with general contours plus the complex contours of the erosion banks around a water course.  Some of the banks are earthbanks (i.e. with tag lines), others black cliff lines.  Notice especially the form line gully in the lower part of the upper circle which is very close to the gully in the centre of the bottom circle.  I have to admit to not knowing the precise control description for the (lower) gully control.  I presume it was (certainly should have been) Southern Gully. The overlap of the circles is significant, but following a complaint the distance between the controls was measured and exceeded 30m.

The use of the two controls here was mainly to split up runners before their common last control.  Was it necessary to do this?  Was this fair?

The important lesson here for all course planners and controllers is to look critically wherever there are any overlapping circles on your master map.  If you have the slightest concern that the runner might see the features in those circles as similar then either move one of them to another feature or use only one of them.