No person shall install a prepayment meter as a primary meter through which gas passes to a secondary meter.
Any person—
shall ensure that a notice in permanent form is prominently displayed on or near each primary meter indicating that more than one primary meter is provided with gas through that service pipe or service pipework.
Where a primary meter is removed, the person who last supplied gas through the meter before removal shall—
Where a person proposes to remove a primary meter he shall give sufficient notice of it to the person supplying gas through the meter to enable him to comply with paragraph (3).