In the old days before dedicated HEMS most operations were conducted as follows and can still be done of course. If you are standing up and calling yourself a dedicated service and cannot comply with the rules, then obviously unless the following applies, you cannot conduct the operation.
With dedicated services now available, unless the operation is the last resort, you would have a difficult case.
NZ Civil Aviation Act 1990
13A Duties of pilot-in-command and operator during emergencies
(1) Subject to subsections (2) and (6) of this section, in an emergency that arises
in flight, the pilot-in-command may breach the provisions of this Act or of
regulations or rules made under this Act.
(2) For the purposes of subsection (1) of this section, a breach of any prescribed
requirement is permitted only if the pilot-in-command is satisfied that—
(a) The emergency involves a danger to life or property; and
(b) The extent of the breach of the prescribed requirement goes only as far
as is necessary to deal with the emergency; and
(c) There is no other reasonable means of alleviating, avoiding, or
assisting with the emergency; and
(d) The degree of danger involved in complying with the prescribed
requirement is clearly greater than the degree of danger involved in
deviating from it.
(3) Subject to subsections (4) to (6) of this section, where an emergency (not
being an emergency that arises in flight) necessitates the urgent transportation
of persons or medical or other supplies for the protection of life or property,
the pilot-in-command of the aircraft or the operator of the aircraft may breach
the provisions of this Act or of regulations or rules made under this Act.
(4) For the purposes of subsection (3) of this section, a breach of any prescribed
requirement is permitted only if—
(a) The emergency involves a danger to life or property; and
(b) The extent of the breach of the prescribed requirement goes only as far
as is necessary to deal with the emergency; and
(c) There is no other reasonable means of alleviating, avoiding, or
assisting with the emergency; and
(d) The degree of danger involved in deviating from the prescribed
requirement is clearly less than the degree of risk in failing to attend to
the emergency.
There is the requirement that if you do take up this option you must clearly report the case. Your report will need to be watertight.
The head of the Rotary Unit is one of the few people I know to be charged under the Regulations and the Act, so he is well experienced in these matters!
52A Failure to notify emergency breach of Act or regulations or
rules
Every pilot-in-command commits an offence and is liable to a fine not exceeding
$5,000 who, without reasonable excuse, fails to comply with section 13A(6) of this
Act (which relates to the notification of breaches of this Act or regulations or rules
made under this Act that are committed during an emergency).