OS maps online do I have to include oxygen tanks in my risk assessment

[deekjcornwell]

Plotting a short route using my OS maps subscription yesterday
3.3k round the village map reading practice fine for an hour and a 1/2 I thought.
then I looked at the route card 7+ hours estimated ??

Rechecked the route same time then looking at the route card I noticed the 3200m climb ? but we only cross 2 contours ?

After some live chat with the OS help desk they said there are some issues with height data in some areas.
so back to the paper maps for planning ?

[ianw]

Possibly. You've got a T2 permit right? You might need to remember sun cream too as you may be above the clouds and the thinner atmosphere will mean you burn quicker.