6.—(1) Subject to the following provisions of this regulation, no vehicle shall stop or remain at rest on the carriageway.
(2) Where it is necessary for a vehicle which is being driven on a carriageway to be stopped while it is on a motorway—
(a)by reason of a breakdown or mechanical defect or lack of fuel, oil or water, required for the vehicle; or
(b)by reason of any accident, illness or other emergency; or
(c)to permit any person carried in or on the vehicle to recover or move any object which has fallen on a motorway; or
(d)to permit any person carried in or on the vehicle to give help which is required by any other person in any of the circumstances specified in the foregoing provisions of this paragraph,
the vehicle shall, as soon and insofar as is reasonably practicable and safe, be driven or moved off the carriageway on to, and may stop and remain at rest on, any hard shoulder which is contiguous to that carriageway or in an emergency layby.
(3) A vehicle—
(a)which is at rest on a hard shoulder or in an emergency layby shall so far as is reasonably practicable be allowed to remain at rest there in such a position only that no part of it or of the load carried thereby shall obstruct or be a cause of danger to vehicles using the carriageway;
(b)shall not remain at rest on a hard shoulder or in an emergency layby for longer than is necessary in the circumstances or for the purposes specified in paragraph (2) of this regulation.
(4) Nothing in the foregoing provisions of this regulation shall preclude a vehicle from stopping or remaining at rest on a carriageway while it is prevented from proceeding along the carriageway by the presence of any other vehicle or any person or object.