Page 48 - Gi flipbook May 2018

IGEM NEWS | Technical Standards

through an advanced meter. An
advanced meter is a gas meter that FIGURE 2: Extent of hazardous areas for vent pipe
either, on its own or with an ancillary
device, can provide hourly measured
gas consumption data and provide
remote access to the gas supplier.
The consumer may require a data
connection for their EMS, either via a
hard connection or via an AMR or
data logger device. Further to this, the
consumer may be bound under
mandatory agreements to monitor
and control their gas consumption,
under such schemes as the Carbon
Reduction Commitment (CRC), the
Energy Efficiency Scheme and the EU
Emissions Trading Scheme.
2. Daily metered (DM) sites
The gas transporter has a regulatory
requirement to provide the meter
readings to the shipper to provide
fiscal reconciliation of the gas
consumption with the gas supplier.
This standard sets out the basis of
legal, contractual and practical
considerations and is intended to
discourage the notion of a “first come,
first served” arrangement. Observing
the legitimate access of the parties
involved with regards to regulatory
entitlement will simplify the
contractual requirements.
PULSE PRIORITY
In addition to the safety related
aspects, this standard also discusses
preferred interconnection options and
circuit parameters. This was the
subject of much debate within the
technical panel.
The overarching principle was
agreed that anyone should be able to
safely connect any piece of equipment
to any other, such that all meter data By far the most significant potential is rated at zone 2. This removes the
(e.g., consumption data via meter source of ignition on a metering need for Exd (etc.) lighting
pulses) is reliably available to all. installation is electrical equipment, • A smaller zone 1 (250mm) at a
This is relatively easy to state in a such as lighting, and electronic creep, because small creeps have
descriptive paragraph, but surprisingly instrumentation. This standard gives smaller flow
difficult to achieve in practice. guidance in these areas. It also • Consideration of how to handle
discusses other information relating to small creeps inside a housing
INSTRUMENTATION such equipment including guidance on • Special conditions added for small
In addition to what may be described interoperability. meter boxes, including downwards
as the ‘commercial’ arrangements of pointing vents (compare non-ideal
installation and pulse priorities, it now The scope of work in IGEM/GM/7B with danger of vandalism) and MP,
remains to explain how hazardous included, but was not restricted to: <1.5m3 volume to be deemed zone 2
areas influence the choice of any • Incorporating the concept of NE
equipment placed in the area. It should • Pros and cons of removing ATEX CHANGES TO ZONING
be noted that all equipment, including certification for LP meters METHODOLOGY AND NEGLIGIBLE
mechanical, should be considered. • Recalculating the data for the EXTENT (NE)
However, in the case of a typical gas software to enable new zone tables The update to IGEM/SR/25
installation, it is accepted that a to be produced incorporated the results obtained
mechanical gas meter, regulator or • Removing the requirement to classify from fluid flow modelling work
pipework, for example, will not be able a zone 2 area inside a meter house undertaken by the Health and Safety
to ignite a flammable gas atmosphere. roof space unless the entire enclosure Laboratory (HSL) that examined how

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