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New requirements for emergency isolation for Multi-layer pipe - ESV guidance on AS NZS5601.1 2022

hello my name is David crew from Energy
Safe Victoria and this presentation is
designed to highlight and provide some
guidance on how to conform with the new
requirements in asnzs 5601 part 1 2022 clause 5.2.11

ESV has developed this presentation and
video demonstration in collaboration
with building an energy Western
Australia and Atco Australia

isnz 5601 part 1 2022 was published on
30 September 2022 containing a new
Clause 5.2.11 the provision for fire emergency
isolation for multi-layer pipe
where multi-layer pipe is used as part
of consumer piping 

the following requirements for fire emergency
isolation shall apply 

the installation shall be fitted with a system that will
shut off the gas supply when the fire
safety system operates

the method of isolation shall be a Class
1 safety shutoff valve that meets the
requirements of as-4629 and automatically isolates the
gas flow to the building 

when de-energized the valve shall operate
when an active fire safety system
operates
and be located prior to any multi-layer
pipe and be as close as practicable to
the gas supply point to the building and
readily accessible

this system shall provide pressure
proving of the downstream installation
prior to the restoration of gas supply

alternatively for a class 1a building in
Australia or detached or multi-unit
darling in New Zealand a system or
device that automatically shuts off gas
supply if gas tightness is adversely
affected by a fire emergency event shall
be provided the system or device which shuts off the
gas supply shall be installed in a
readily accessible location as close as
practicable to the gas supply Point
prior to any multi-layer pipe

this device shall be sized and
commissioned in accordance with the
manufacturer's instructions to ensure
safe and correct operation and avoid
nuisance tripping

multi-layer pipe has less durability and
mechanical strength than metallic piping
when subjected to fire

class 1a buildings are defined in a
National Construction code or NCC here
in Australia

devices that automatically shut off gas
supply may be activated by methods of
sensing pressure loss or excessive gas
flow conditions

this clause also applies to the
alteration of consumer piping using
multi-layer pipe in an existing
installation that does not apply to the replacement
of gas appliances in an existing installation 

now that a Class 1 safety shutoff valve in
this context is a valve and Associated
controls that shuts off or prevents the
supply of gas when a fire safety system
is activated

a definition of the fire safety system
has been included in ASN zs5601 part one.

this was included as a result of changes
to the requirements for our modulate
pipe

this definition was provided with the
assistance of the Australian building
codes board. Be mindful there has been an
amendment to this cause. 

if you choose to use multi-layer piping
for any or all of your installation
you must comply to protect the
installation from any potential fire
event. 

you must comply with any local
state or territory regulatory
requirements and select the correct
valve or system for the job you are
completing

clause 5.2.11 requires the use of specific
isolation devices to be fitted if there
is multi-lay pipe installed within the
building

the Clause states that if multi-layer
pipe has been installed the installation
shall be fitted with a system that will
shut off gas supply when the fire safety
system operates

the isolation valve installed must be a
class one safety shutoff valve and be
located prior to any multi-layer pipe
and as close as practicable to the gas
supply point or the gas meter

the ag6 committee has included this
requirement due to durability and
mechanical strength that multi-layer pipe
has when subjected to fire

extensive testing and research has been
conducted on this issue
in a commercial building such as a
high-rise apartment Shopping Center or
restaurants

you'll need to provide protection in the
form of a solenoid safety shutoff valve
that incorporates a pressure proving
device

the system must be connected to the
building's fire safety system be
installed and commissioned as per the
manufacturer's installation instructions
and be as close as practicable to the
gas supply point prior to any
multi-layer piping

the system must be really accessible for
maintenance testing and repair

most importantly the device must be fit
for purpose 

you must also pressure prove
the downstream part work of the
installation prior to gas being
reinstated 

some Gas Distribution companies have specific requirements
in relation to the location of auxiliary
equipment in and around gas meter rooms
and gas meters 

it is important to check these requirements before installing the
valve in class 1a buildings such as a single
dwelling being a detached house or one
of a group of attached drawings being a
townhouse rather houses or the like
where there is no fire safety system
installed you will need to consider
installing one of the following devices

these devices need to be installed as
close as practical to the gas supply
Point prior to any multi-lay piping and
be really accessible for maintenance
testing and repair

it is also important to note in addition
to calls 5.2.11 of ASN zs5601 clause
5.3.16 now prohibits the installation of
multi-layer piping above ground external
to a building, therefore multi-layer piping is no
longer permitted to be installed outside
even when protected from UV

when installing any of these devices it
is important the valve is fit for
purpose and the manufacturer's sizing
installation and commissioning
instructions are followed

we will now look at some examples of the
different types of devices suitable for
installations in class 1a buildings in
their installed positions

the first type of example we will look
at is the excess flow valve or efv

there are a number of different
manufacturers and suppliers of excess
flow valves and not all valves are the
same when installing any equipment 

the manufactures installation instructions
must be complied with. some valves have a
limitation on their use and may only be
installed in the vertical position for
example

the excess flow valve must be installed
prior to the installation of any
multi-layer pipe as close as practicable
to the gas supply point and be readily
accessible

some excess flow valves have a maximum
capacity or operating range and not all
valves will operate with a low Inlet gas
supply pressure

this is why it is extremely important to
follow the manufacturer's sizing guide
to ensure the valve you intend to
install is fit for purpose

fitting an incorrectly sized excess flow
valve could deem installation
non-compliant as the excess flow valve
may not operate when the multi-load
piping is compromised 

an incorrectly sized excess flow valve may also cause
engine stripping becoming an inconvenience for your customer 
and a costly mistake for you

additional valves may be required when
sizing in accordance with the
manufacturer's installation requirements

the video on the screen was filmed under
controlled conditions. the video shows an
excess flow valve installed at the
outlet of the gas meter and a normal
operating conditions gas will be
available to all appliances when a
compromised multi-layer pipe is detected
Downstream of the valve such as a leak,
the valve will shut off the supply of
gas by way of a pre-tensioned
spring-loaded disc.

once the downstream fold has been
rectified the excess flow valve will
automatically reset under most
circumstances.

this occurs by way of a small orifice
which allows the pressure on both sides
of the valve to equalize allowing the
valve to automatically reset.

next we will look at Under Pressure
shutoff devices or more commonly known
as upso devices

most of you will be familiar with over
pressure shutoff devices or opsos, not to be confused with an Under
Pressure shutoff device or upso, which look and operate in a very similar
manner 

the difference is an upside device will shut off gas supply if the
gas pressure Falls below a predetermined
set point in the event of a fire and the
multi-layer pipe is compromised 

the Under Pressure shutoff device will sense
a change in set point pressure and shut
off the gas supply until the fold is
rectified

once the fold is rectified the upside
device can manually be reset

the Under Pressure shut off device must
be installed prior to the installation
of any multi-layer pipe and is closest
practicable to the gas supply point and
readily accessible most upso devices are
suitable for use with all Inlet gas
pressures

it is imperative to follow the manufacturer's sizing
installation and commissioning
procedures when choosing and setting up
these types of devices

the video on screen was filmed under
controlled conditions the video shows an
Under Pressure shut off device installed
at the outlet of a gas meter and a
normal operating conditions gas will be
available to All Gas Appliances
when a compromised moduloid pipe is
detected Downstream of the valve such as
a leak, the valve will shut off the gas
supply by way of a mechanically operated
plunger as can be seen by the green
indicator on the video

once the downstream fold has been
rectified the Under Pressure shutoff
device can be manually reset

now we will look at an electronic safety
shutoff system. these devices come in many different
forms but essentially consist of a gas
solenoid shutoff valve that is wired
back to a relay panel or control device

the relay panel or control device is
then connected to an appropriately
installed and compatible smoke detector
in the event of a fire the smoke
detector will send a signal to the relay
panel or control device which in turn
will shut off the power supply to the
gas solenoid shutoff valve stopping the
supply of gas and rendering the
installation safe

the solenoid must be the type that files
safe for example if there is no power
supply the device is in the closed
position

the solenoid component of this type of
device must be installed prior to the
installation of multi-layer pipe and as
close as practicable to the gas supply
point and be readily accessible

once the fault condition is rectified
the devices will either automatically
reset or have a manual reset function on
the control device

please remember that Gas Distribution
companies may have specific requirements
in relation to the location of ignition
sources around gas meters

you'll also need to consider the
clearances to ignition sources when
installing this type of device adjacent
to natural gas meters LPG cylinders and
LPG tanks

this particular system consists of three
main parts the control solenoid valve
and smoke alarm the main control system
has a status indicator and audible alarm
along with a manual reset function local
requirements for clearances to gas
meters should be checked before solenoid
valve is installed

when the green light is shown gas is
available when a smoke detector alerts
due to a fire event it sends a signal to
the control which then can be seen here
in this simulated event the status of
the system goes from green to red and an
alarm is audible the control then stops
power to the solenoid valve and shuts
off gas supply

I reset up both the smoke alarm and
control system will be required before
gas can be reinstated to the
installation

multi-layer pipe has less durability and
mechanical strength than metallic
piping when subjected to fire
gas regulators throughout Australia and
New Zealand are aware of a number of
incidences where multi-layer pipe has
been compromised during a fire event
resulting in serious injuries and
fatalities

it is important to note that in most
cases the multi-layer pipe was not the
cause of the fire but helped accelerate
the spread of the fire as a result of
its failure

extensive testing has been carried out
by Energy safe Victoria on multiple
examples of different piping materials
demonstrating that multi-layer pipe has
less durability and mechanical strength
than metallic piping when subjected to
fire

in the example shown on the screen the
multi-layer pipe has been exposed to
radiant heat of 650 degrees Celsius

it failed after six minutes of exposure.
in real world conditions the heat may be
direct flames and up to 1200 degrees
meaning the pipe could possibly fail in
a shorter period of time 

as stated previously multiple real world examples
have also demanded the committee
responsible for ASN zs5601 which is
ag006 make changes to the standard
the requirements being introduced are
already a requirement in some European
and American markets

it is important to note that some valves
are sized according to the amount of
cubic meters they are expected to pass
before shutting off

as/nzs5601 part 1 2022 appendix f
able F 0.1.5 gas property states that
the heating value of natural gas is 38
Mega joules per cubic meter and for LPG
it is 96 megajoules per cubic meter,
therefore if you had an installation
with a continuous flow hot water unit
rated at 198 megajoules an hour a
cooktop rated at 40 megajoules an hour
and a gas central heating system rated
at 120 megajoules an hour your total gas
flow rate for the installation would be
358 megajoules an hour.

the formula to convert these to cubic
meters is as follows:
total gas load in mega joules an hour
divided by the heating value of the gas

in this scenario we will use natural gas
with a heating value of 38 megajoules an
hour

358 megajoules an hour divided by 38
megajoules equals 9.42 cubic meters

you would be required to fit a device
suitable for 10 cubic meter
installations

if the installation was to be supplied
or operate on LPG you would need to
change the heating value to 96
megajoules per cubic meter

for other conversion factors you should
refer to asnzs5601 part 1 2022 appendix B
it is important to follow the
manufacturer's installation instructions
the devices should only be installed in
the position and direction that they
have been designed and installed for
a correctly sized valve will eliminate
Mission stripping and avoid costly call
outs 

some pressure drop across the
different devices can be expected and
this should be considered when sizing
the consumer piping

all the devices shown during this
presentation will meet their comments of
the new standard as long as they are
installed sized commissioned according
to their respective manufacturers
installation instructions 

this is not an endorsement of any particular device
rather a presentation outlining a
selection of available devices that will
meet the requirements

you must read the instructions for every
installation as they will all differ and
in some situations you may be required
to install additional valves in your state 

for further information you can contact the technical regulator
on your screen

ESV would like to acknowledge the
support of the following organizations
for their assistance in the development
of this video

I'd like to thank you very much for your
time
 

Reviewed 08 September 2023