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I'm unsure how to use SAC scale based on the wiki page. Are you supposed to take the highest level on the basis of any of the criteria, or does the path need to fit all of the criteria?

For example, an easy scramble in a gully 1:1, solid rock almost cut into steps, might

  • 'require use of hands for balance' (T3),
  • not be exposed (T3) but present a fall hazard (T2),
  • have no navigation difficulty and be suitable for trainers (T1) but require some sure-footedness (T2).

So averaging out this might be T2, lowest seems T1 and highest T3 (although a skilled mountaineer could climb it upwards rarely using their hands but would choose to in places given the availability of excellent holds and steepness).

Also, is it appropriate to use sac scale over a relatively short stretch (e.g. a 50m scramble). Thanks.

asked 14 Aug '22, 21:42

TrekClimbing's gravatar image

accept rate: 0%

edited 14 Aug '22, 22:13

In general a UK Grade 1 scramble will be T3 or T4 (usually the latter). Grade III scrambles may exceed the top of T6 (especially when on very loose rock). Your situation sounds similar to this stretch of path I mapped as T3 some years ago in Cwm Glas Mawr.

The usual rule would be to grade the entire route with the highest degree of difficulty, but some discretion is needed. In particular if there are alternative routes then grade only the part where someone is committed to passing the crux. By pure coincidence, yesterday I read a nice report of a traverse over Cadair Idris by an experienced Swiss hiker/mountaineer who graded the whole (including Fox's Path) as T3 too.

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answered 15 Aug '22, 14:51

SK53's gravatar image

SK53 ♦
accept rate: 22%

Thank you very much. I'll have more confidence in using this tag which I have stared at in befuddlement for quite a while now! As an aside, I often see note tags on footpaths such as this (and both of these linked examples) that I think might be better as descriptions? I don't understand why the difficulty is being communicated to mappers and not end-users. Thanks again.

(15 Aug '22, 15:27) TrekClimbing

Well mine was explicitly for mappers because I didnt know if people in UK would be familiar with the SAC Scale. The T3 grade does mean some use of hands may be required. Fox's path is another case. I did it a long time ago on both ascent & descent and didnt have any issues, but I understand that it much more worn now. I think the correct approach is to use a hazard=* tag. I'd quite like a systematic list of typical hazards for walkers (e.g., tides, quicksand, fastflowing river, fast rising river, loose rock, rock fall, serac fall, crevasses, cornice, avalanche, slippery when wet, exposed, risk of falling etc)

(15 Aug '22, 21:28) SK53 ♦

Okay, thanks. I'm certainly not familiar with sac scale apart from as an OSM tag. I've added sac_scale to the way and those around. I've also added a sac_scale_rationale to explain. Having gone up it again today with someone less confident I may have underestimated it but I'm just not familiar enough with this grading system (or indeed enough other scrambles) to be sure.

(16 Aug '22, 01:06) TrekClimbing
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question asked: 14 Aug '22, 21:42

question was seen: 515 times

last updated: 16 Aug '22, 01:08

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