BCRA Grades

Martin Ellis Martin Ellis" <mjellis@tesco.net
Mon, 13 Jan 2003 14:57:05 -0000


In the new BCRA Cave Surveying booklet by Anthony Day there has been a
change in the definition of a BCRA Grade 5 survey from that given in the old
cave surveying booklet.

The original definition was "Horizontal and vertical angles accurate to +/-
1 degree;  Distances accurate to +/- 10 cm; Station position error less than
10 cm."

The new version is "Horizontal and vertical angles measured to +/- 1 degree;
Distances should be observed and recorded to the nearest centimetre and
station positions identified to less than 10 cm."

This is a significant change.  BCRA Grade 5 is now considerably easier to
obtain as now you only have to be precise to +/- 1 degree, whilst previously
you had to be accurate to +/- 1 degree.

Is this "dumbing down" of BCRA Grade 5 a deliberate change by BCRA or is it
due to a misunderstanding of the original definition?

Martin Ellis