BCA 2010 - ABCB - Australian Building Codes Board

like. Compare that to Australian and US
codes; after the 25 metres you need two
stairs in all cases, regardless of the travel
distance in the corridor.
In the Australian context, there have
been fire engineered options developed
that look at single stair solutions, but
in the U.K the single stair scenario is
the accepted way of doing it under the
prescriptive code, and it is because of
the evacuation methodology that it
is used, compared to here where the
approach is accepted.
ABR Bulletin: As a fire engineer, what
are some of the better options you have
seen throughout the world in terms of
codes?
WB: That is an interesting question,
because I think one of the good things
about the Australian system and the
Australian codes is the fact that you
have a framework to actually assess
performance fire engineered solutions
against.
The BCA performance requirements set
down what you need to achieve and
what you need to look at. In contrast,
the U.K regulations have a functional
requirement, which is a single statement
on what you need to achieve. This tends
to lead to an inconsistency in how fire
engineering is applied.
The US codes are more prescriptive
when it comes to fire engineering. For
example, NFPA 101, Chapter5, sets out
a process for how fire engineering is
done and what type of fire scenarios you
should be looking at.
But I think what is interesting is
the differences between how fire
engineering is used or perceived
between the world and Australia, and
this is where Australia is different to
other countries. Elsewhere in the world
the fire code consultant and the fire
engineer are usually the one person that
produces a holistic fire strategy covering
all fire safety requirements including
any prescriptive code requirement as
well as addressing any fire engineered
solutions. In Australia you typically have
a Building Surveyor, and a Fire Engineer.
The Building Surveyor does the code
consulting, and the Fire Engineer
supports the Building Surveyor and does
the technical analysis of solutions.
In all parts of the world they all deal with
the typical issues such as getting the
people out and getting the fire brigade
in, but as a consultant your agreement
changes depending on the country you
work in.
A fire engineering consultant’s role in
Australia, the U.K and the US, has a remit
of making sure the building achieves fire
safety in a cost-efficient manner so fire
engineering is more readily used.
In places like the Middle East it is about
de-risking the scheme. The schemes can
get built so quickly, you cannot afford to
spend a lot of time in negotiation with
authorities, so it is about making sure
that the scheme is robust enough to
ensure it is easily approved.
For example, we recently designed
a very large and complex mixed use
building in the Middle East where the
architects were based in London and
Chicago and a structural and mechanical
engineering designer based in Paris.
We did the entire design from scratch
facing geographical and programme
challenges in 16 weeks. Elsewhere, the
design of a building of this size and
complexity design could be anything up
to 12 to 18 months long.
When you have a longer design program
you are actually able to enter into a
meaningful dialogue with authorities
around how the design should be
progressed. When the design program is
compressed as much as in my example
the role of the fire engineer is to de-risk;
to ensure that what is being designed in
a hurry is safe and will be approved.
ABR Bulletin: In your presentation on the
Strata Tower within the London Borough
of Southwark, you mentioned some
novel and innovative approaches in fire
engineering, such as tying the sprinkler
systems into the domestic water supply.
How radical an approach is this?
WB: It was new in a U.K context,
although domestic sprinkler systems are
not new. If you look at low rise sprinkler
systems, you would see that they do
actually come off domestic supplies.
What we did was to take that approach
and apply it to a 43 storey building.
Our rationale in applying this approach
was that water for domestic use needs
to be pumped up and stored in the
building to cope with peak demands
such as when people get ready in the
morning and that this level of storage
far exceeds anything needed for the
operation of the sprinkler system.
The system we designed also connected
the sprinklers to the toilet cistern
creating a flow-through system. This
means there was no problem with
mixing the sprinkler water with the
potable supply as there was not an
opportunity for the water to stagnate
in the sprinkler pipes. It also means
that system reliability is maintained,
because every time someone flushes
the toilet, you know you have water in
the sprinkler system. It was a simple but
effective approach.
It was novel in the U.K context, firstly
because at that time buildings of this
height did not need sprinkler systems.
In 2007 they introduced a requirement
to install sprinkler systems in buildings
over 30 metres high, but at the time of
its design, the building did not need
it. Secondly, it was novel because it
was not as “belts and braces” as a fullyfledged
sprinkler system with separate
infrastructure, pumps and tanks.
ABR Bulletin: It sounds very much
like the whole-of-system approach
engendered in AS1851.
WB: Exactly. It is all about reliability and
making sure the water is there to do
what it is meant to do, when it needs to,
and designing the system in this way
achieves that in a simple design.
Wayne has recently returned to
Australia and is now a Director of
Philip Chun Fire & Risk based in
Brisbane.
www.philipchun.com.au
INTERNATIONAL REGULARTORY DEVELOPMENT
Australian Building Regulation Bulletin
• 37