Hi Bill
The quote you mentioned is the guidance given to Atos HCPs, which as I said in my previous post, we don't agree with it. You should be able to either sit or stand without alternating.
I'm afraid the law does clearly state that the activity should be carried out for 30 mins/1 hour and not hour after hour, but you would have to be able to repeat the activity in a reasonable amount of time.
Regards
Derek