Glossary of Terms
Active regulator
A pressure regulator installed in a series with a monitoring regulator for the purpose of controlling the downstream pressure.
Appliance burner pressure
The pressure of gas supplied to the burner injector, downstream of the controls within the appliance, measured at or close to the burner. This pressure is used to set and control the gas throughput rate of the burner.
Boundary to Meter Measurement
This measurement is based on the length of service pipe used in the construction of the service, not the direct line from boundary to meter. The measurement in a straight line may be 20 metres from boundary to intended meter position, however if an extra 5 metres of service pipe is required to avoid an obstacle, then the boundary to meter measurement will be determined by the pipe length, i.e. 25 metres, and the Channel Partner will be charged for the extra meterage.
BTU
British Thermal Units. Imperial measure of energy (similar to megajoules). 1 BTU is 1055 joules.
Burner
A device that positions a flame in the desired location by delivering gas and air to the location so that controlled, continuous combustion is achieved.
Combustible material
A material which will ignite and burn and includes material which has been flame proofed.
Combustion products (‘products of combustion’)
The constituents resulting from the combustion of a fuel with air, oxygen or a mixture of the two, including the inert gases associated with the fuel and the air but excluding any other diluent or containment.
Condensate
The liquid that separates from gas (including flue gas) due to a reduction in temperature.
Connection (service pipe)
The pipe which runs from the gas main and ends at the customer’s gas meter or meter valve.
Consumer piping
A system of pipes, fittings, components and equipment which conveys gas from the outlet of the consumer billing meter installation, or for gases stored in a tank or cylinder from the outlet of the first gas pressure regulator, to the gas appliance inlet.
Please note:
In the case of a reticulated LPG system, the “first gas pressure regulator” refers to the first regulator on the site if no meter is installed.
Cover
The depth to the top of the pipe measured vertically to nominal ground level.
Craftsman gasfitter
A person whose name appears for the time being in the register of craftsman gasfitters maintained under section 20 of the PLUMBERS, GASFITTERS, AND DRAINLAYERS ACT 1976 Act.
Drill(ing)
The method of underground construction where the use of a Directional Drill is utilised, normally used for distances over 30m.
Directional drill
A mechanical ‘mole’ is used to tunnel below ground to where a gas meter will be located. Two small holes dug; one at the beginning and one at the end of the pipeline. This method generally applies to longer services only (over 30 metres and up to 100 metres).
Dig your own trench (DYOT)
Trench provided by developer or customer for installation of gas pipe. See PIT.
Easement
The legal terms for a right granted by a landowner (“the grantor”) to another landowner or a network operator (the “grantee”) allowing the grantee to do something on the grantor’s land. The easement will usually allow the grantee to place assets on the land and enter onto the land to maintain and upgrade them. The easement is registered on the title to the grantor’s land and will usually prevent the grantor from developing the area of land affected by the easement. Easements are not needed for assets on roads.
Enclosure
A compartment, enclosed area or a portioned off space primarily used for the installing of a gas appliance, gas cylinder, meter, gas pressure regulator or other associated equipment.
End Consumer Load Group
A tariff category that is directly dependant on the end consumer’s maximum hourly consumption of gas or residential status.
Fittings
Everything used, designed or intended for use, in or in connection with the generation, conversion, transformation, conveyance, measurement, or use of gas.
Flue
The pipe or duct through which combustion products are conveyed from a gas appliance to a discharge point, including any draught diverter and associated duct, barometric device, fan, or other fittings in the duct.
Balanced flue
A flue system in which the combustion products are discharged at the same height and atmospheric pressure as the combustion air inlet of a room sealed appliance.
Common flue
A flue system designed to carry the combustion products from two or more appliances.
Natural draft flue
A flue in which the draught is provided by the buoyancy effect of the hot gases in it.
Open flue
A flue system containing a draught diverter or canopy.
Power flue
A flue system in which combustion products are removed from the gas appliance by a fan in the flue.
Flue cowl
A device placed at the end of a flue and designed to prevent the entry of rain or birds and minimise the disturbing effect of wind while not hindering the discharge of flue gases.
Flue gases
Combustion products plus all diluents and containments.
Flue terminal
The point at which flue gases discharge from a flue.
Gas appliance
Any appliance that uses, or is designed or intended to use gas, whether or not it also uses, or is designed or intended to use, any other form of energy.
Balanced flued appliance
A gas appliance which has air for combustion ducted from, and combustion products ducted to, a common terminal.
Non flued gas appliance (Flueless)
A gas appliance designed to discharge its combustion products into the area where the appliance is located.
Open flued appliance
A gas appliance with a flue system containing a draught diverter or canopy.
Power flued appliance
A gas appliance with a flue system in which combustion products are removed from the gas appliance by a fan in the flue.
Room sealed gas appliance
A gas appliance designed so that air for combustion does not enter from, or combustion products enter into, the room in which the gas appliance is located.
Portable gas appliance
A gas appliance designed to be carried by the user from place to place, as required.
Gas consumption
The rate of energy consumed by a gas appliance under specific conditions and usually expressed in megajoules per hour (MJ/h).
Gas demand
The peak instantaneous demand for gas that the main or service is designed to pass with a specified pressure loss.
Gas load
The total gas consumption of all downstream gas appliances (from the GMS).
Gas Measurement System (GMS)
A system for measuring the quantity of any gas or the energy content of any gas.
Gas meter
See Gas Measurement System.
Gas Supply Pressure
The pressure of the gas supplied into the installation pipework measured at the outlet of the GMS or custody transfer point. This pressure will normally be controlled by the service or cylinder regulator at a predetermined level but can vary under fault conditions.
Gastight
The condition of a gas installation or gas pipework in which any leakage of gas is at a sufficiently low rate that no hazard is likely to ensue.
Gigajoule (GJ)
One billion joules. Annual gas usage of residential and commercial customers measured in gigajoule.
ICP
The Installation Connection Point.
Ignition source (or ‘source of ignition’)
A source of energy sufficient to ignite a flammable mixture and includes, but is not limited to naked flames, exposed incandescent material, electrical welding arcs, any electrical or mechanical equipment not suitable for use in hazardous locations.
Industrial Connection
An industrial connection is a load over 200 scm/hr.
Joule
A standard international unit of energy.
Kilowatts
A unit of power equal to 1,000 watts.
Kilopascals (kPa)
Unit of gas pressure. kPa is the most common pressure measurement and is used to express gas appliance and distribution network operating pressures.
Liquid Petroleum Gas (LPG)
Propane, propylene, butane, butylene or iso-butane, or a mixture consisting wholly or principally of any two or more such substances, whether or not the mixture contains any other hydrocarbon.
Load
The term used for the amount of gas consumption on the network. It is directly proportional to the end consumer’s appliances installed.
Main
A continuous pipe used for the conveyance of gas from points of supply, generally running within the road corridor and from which individual service pipes or other parts of the distribution network are supplied.
Mainsfronter
A consumer whose property is situated directly in front of an existing gas main situated on either side of the road where a service connection can be installed at right angles from the main to the meter.
Mains Extension
An extension from the existing gas mains system to the front of a property, allowing a service pipe (connection) to be connected at right angles to the gas mains. It is constructed within the road reserve, or land which will be deemed road reserve (e.g. new subdivisions).
Maximum Demand
The quantity of gas expressed in mega joules per hour (MJ/hr) or standard cubic meters per hour (scm/hr) necessary to supply the total load under consideration.
Megajoule (MJ)
One million joules. Gas appliance inputs are most often measured in MJ.
Meter Bank
A group of meters (GMSs) grouped together off the same service riser through the use of a manifold that connects into the riser valve. Every meter (GMS) in the meter bank must have its own ICP number.
Open Cut
A method of construction using a trench. Most commonly used in rock conditions or where there are site hazards such as trees.
Operating pressure
The gas pressure that any part of the gas installation is set to or will be subjected to under normal operating conditions.
Petajoule (PJ)
1015 joules. Gas flowing through the distribution network is measured in petajoules.
PIT– Pipe In Trench
Trench provided by others for installation of gas pipe.
Plant room
A room designed to accommodate one or more gas appliances, or other equipment, in which the gas appliance can be fully maintained, and which is not normally occupied or frequented for extended periods.
Pressure
Pressure above atmospheric pressure (gauge pressure), Unless otherwise stated is expressed in kilopascals (kPa) above atmospheric pressure, i.e. “gauge” pressure.
Distribution pressures are classified under three main headings:
| 1. | Low Pressure LP up to but not exceeding 7 kPa |
| 2. | Medium Pressure MP1 greater than 7 kPa but not exceeding 110 kPa MP2 greater than 110 kPa but not exceeding 210 kPa MP4 greater than 210 kPa but not exceeding 400 kPa MP7 greater than 400 kPa but not exceeding 700 kPa |
| 3. | Intermediate Pressure |
High Pressure Systems are systems above 2000 kPa, and are covered by NZ Standards 5223.
Pure Energy® Accredited Channel Partner
A participant in the gas industry who facilitates connections to the Vector gas network.
Right of Way (“ROW”) Consent
Required on all new gas connections where new gas service pipes are laid down a shared driveway where that driveway is used to service two or more properties or dwellings, and where the ownership of the driveway is shared/used by more than one title deed owner/tenant.
Road Opening Notices
This is the permit that needs to be obtained from local council prior to construction work proceeding in the road reserve.
scm/hr
Standard cubic meters per hour. Maximum hourly quantity of gas required in one hour period.
Service
Connection from the mains to the customer’s meter. The pipe which runs between the main and end consumer’s gas measurement system, or the point of custody transfer of the gas, if no GMS exists. Owned by the distributor. Note: A service should ideally be laid at right angles to the road.
Soil conditions
- Hard rock
Material that requires the use of explosives or the constant use of pneumatic tools for removal, and where the rock is of sufficient size to prevent it being removed from the surrounding mass by an excavation machine suitable for the designed size of the trench. This includes mass concrete other than concrete forming part of an existing road or building foundation.
-
Loose rock
Materials consisting of papa, mudstone, sandstone, scoria and the like including the Waitemata group. The rock is generally removable by excavation from the surrounding mass by the normal operation of an excavation machine suitable for the designed size of the trench. The use of pneumatic tools may be required to aid removal
TBM
The chemical name of the odorant added to gas.
Temporary disconnection
The interruption of the gas supply, generally for a short duration. Usually performed when there is non-payment of an account, or other commercial reason; equipment replacement, or maintenance to the network is performed; an outage, or loss of supply for other reasons.
Terajoule (TJ)
1012 joules. Annual gas usage of industrial customers is measured in terajoules.
Thrust
The method of underground construction where two pilot holes are dug and a bore is thrust through from the lead hole through to the end hole. This method is generally effective up to 20 metres, if distance is greater see Drill.
Transitional disconnection
The interruption of the gas supply, generally for an unknown duration, which may be short or long term. This is for a significant installation or property modifications and alterations, performed at the consumer’s request, where the consumer does not require removal of the GMS and/or service riser from the site, when a property has become vacant, or there are concerns about the safety of the gas installation.
Trench
The hole provided by the end user/developer from front boundary to meter position.
Working pressure
The pressure in a gas installation where any or all gas appliances are in operation.