Err, what? Ask who to wait? The tree-cutters or the ventilated
patient?

The patient.

If the tree work takes exactly three hours then it matters not a jot
whether they do it before, during or after my boys have dinner - it's
still a three-hour period for which the patient needs to be prepared.

It is not just the 3 hours your power was off. Suppose you were a
patient on a ventilator who had seen the cables arcing and reported the
problem in the morning. Would you have been happy for the work to be
delayed until the next day (or the day after that - see below) in order
to allow consumers to be given notice of the disconnection - something
which very probably can't even start to be done until someone has
visited the site and reported back?

I am unclear as to how much delay would be needed to leave you less
disgruntled. How much notice of disconnection would you consider
reasonable and when could it reasonably be given? Eg would you be
content to be phoned at 03:00 to be told the power would be off from
07:00 to 10:00? Or would you want them to leave the call until the
following morning and postpone the work for 24 hours so as to contact as
many people as possible?

None of this means I wouldn't be annoyed if the power went off
unexpectedly for 3 hours. But it happens sometimes (even here in the
middle of London). And I don't want to pay for an electricity supply
where it never happens: the price of perfection is prohibitive

By the way, if the company is forced not to undertake the tree-cutting
immediately owing to the presence of a ventilated patient who needs
time to prepare or be moved elsewhere, and someone is killed on the
street at 5pm by an arcing power-line/tree, I assume the company will
still be liable?

I rather doubt that question admits a simple answer. But I am fairly
sure that the company's defence to *any* claim would be weaker if it
delayed action in order to identify the customers who would be affected,
to give those customers notice of the time they would be disconnected,
and then wait until that time before starting work.

--
Robin
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