Where the ECV sits and what must accompany it, the notices and seals meters need, and what happens when a meter is removed.
Everything in this topic comes back to one question: in an emergency, can somebody who is not you turn the gas off quickly?
The emergency control valve
The ECV is the means of shutting off the supply to the installation. It sits at the inlet to the installation, adjacent to and upstream of the meter, and the requirements on it are all about that emergency:
- Readily accessible. Not behind a fixed panel, not needing furniture moved, not somewhere a
householder would have to hunt for it while they can smell gas.
- Hand-operable. No tool, no key, nothing held by the supplier. If it needs something you
have in your van, it is no use to the person living there.
- Labelled. A safety notice displayed at or near the valve, telling the user what to do in a
gas emergency.
A valve that is hidden, or that needs a supplier-held tool, fails the purpose even if it works perfectly.
The regulator
The regulator built into a domestic meter installation reduces the incoming service pressure and holds it steady as demand changes. It has to stay accessible for the same family of reasons as the valve: it is a device that can fail, and one that has to be inspected and worked on.
Siting and enclosures
A domestic meter installation must be readily accessible, protected, and not shut inside an unventilated enclosure.
⛔ Boxing in a meter without ventilation or access is not a cosmetic decision. It does three things at once: it hinders inspection, it hinders operation of the controls in an emergency, and it removes the safe dispersal any small escape would otherwise have. Ventilated meter enclosures exist so that gas which does escape goes somewhere harmless instead of collecting in a sealed void.
If a customer asks for the meter to be boxed in, that is the conversation to have: access, operation and ventilation are what the box has to preserve.
Notices at the meter
- Where the valve is. If a meter is installed or moved more than 2 m from the nearest upstream emergency control, or out of sight of it, gas may not be supplied through it for the first time until a permanent notice on or near the meter says where that control is (regulation 15(2)).
- Secondary meters. Where a primary meter feeds secondary meters, a permanent line diagram showing all the meters, the installation pipework and the emergency controls goes on or near the primary meter and every emergency control connected to it, and it is updated whenever the layout changes (17).
- Several primary meters on one service. A notice on or near each primary meter says that more than one primary meter is supplied through that service (16(2)).
Regulators and meter connections
- The regulator on a primary meter must automatically keep downstream fittings from pressures above those they were designed for. Where gas reaches the regulator inlet at 75 mbar or more, a second automatic device must protect those fittings if the regulator itself fails (14(1)).
- Regulators are sealed once installed. Only the transporter, or someone acting for them, may break the seal on a meter regulator fed from the main. The seal on an appliance's own regulator may be broken by the engineer setting that appliance up, who must apply a new seal as soon as practicable (14(5) to (7)).
- A meter whose bosses or side pipes are held on by soldered joints alone must not be given rigid pipe connections, because pipework strain would land on those joints (12(5)).
The site and the meter box
- The site must not adversely affect the means of escape from the premises in a fire, must keep the meter clear of damage from electrical apparatus, and must leave it readily accessible for inspection and maintenance (12(1), (3) and (4)).
- An external meter box or compound is built so that escaping gas disperses to the open air rather than into the building or the wall cavity. Nothing readily combustible may be stored in it, and a lockable box needs a suitably labelled key for the consumer (13).
When a meter is removed
If a primary meter comes out and is not refitted straight away, the service valve that controlled only that meter is closed, the emergency control's outlet is sealed with an appropriate fitting, and any live pipe is clearly marked as containing gas. Where there is no such service valve and no meter has been refitted within 12 months, the service is disconnected as near the main as is reasonably practicable (16(3)).
*Original revision guidance; confirm siting, labelling and enclosure requirements against the GSIUR ACOP and BS 6400.*
Something wrong, unclear or out of date? Report an issue with this note.