Joe, when you say 'arrest block' do you mean an inertia reel block or the fall arrest block on the lanyard?
Option 1 is not high enough if they are using a fall arrest lanyard as it extends to around 1.7m and option 2 is a non starter. If you can't eliminate the chance of a fall, then you must use fall arrest.
Look at the possibility of using inertia reels attached directly to the back of the harness as opposed to the lanyard.

Joe, further to the two previous postings, in the hierarchy of working at height fall restraint is preferred over personal fall arrest, however it may not be practical to use either method and hence you may have to consider the tertiary method - collective fall arrest systems ie netting, air bags or crash decks.

I would also add that a competent contractor should be able to decide which is the safest method for the job. Some while back I refused to allow contractors to work on a roof (40ft pitched) because their method statement did not properly reflect the risks and controls associated with the work. The contract was re-tendered.

Like you I am not convinced the method they have suggested is safe, for fall restraint the anchorage point must be fixed above head height. There is a safe ratio for all arrest but for the life of me I cannot remember what it is - tricky stuff this W@H!

This is from leading edge safety, Ray.

As a Guide when using 2M length lanyards the fall distance required (to provide adequate clearance to the fallen operative) is 5.2M when attached above head height, 5.75M when connected at shoulder height and 6.75M when attached at foot level.

Read more: http://www.leadingedgesa...nyards.php#ixzz2Gl7EwlRO