<p dir="ltr">Just to clarify the australian BCA requirements: all habitable spaces including machine rooms, switchrooms, etc. must be provided with fresh outside air. The levels required are stipulated in AS1668 but typically work out at around 1 l/s per m2 for most data centre spaces. </p>
<p dir="ltr">Hospital operating theatres are actually provided with 100% outside air via HEPA filtration with surrounding service corridors kept at approx -ve 20Pa pressure to ensure that no "dirty" air enters the theatre.</p>
<p dir="ltr">Even if it was not a BCA requirement there is a need for fresh outside air in a data centre keep ot at a higher pressure than surround areas to ensure that "dirty" air does not enter the technical space.<br>
</p>
<p dir="ltr">Regards</p>
<p dir="ltr">Tony de Francesco<br>
Technical Director<br>
P.U.E. Pty Ltd<br>
Mob: +61 (0) 457 701 179<br>
Email: <a href="mailto:tonyd@pue.com.au">tonyd@pue.com.au</a></p>
<div class="gmail_quote">On 13/01/2014 8:13 PM, "Matt Perkins" <<a href="mailto:matt@spectrum.com.au">matt@spectrum.com.au</a>> wrote:<br type="attribution"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000">
<div>That's good info Bevan, <br>
I wonder if the building code requires that fresh air be injected
into the entire building or all rooms within the building. I
wonder if Hypoxic fire prevention could be employed in small
computer room type environments or data centers where division
into smaller rooms or where cold/hot aisle for example. I guess
not useful information for centers with large floor plates but
may be useful in power room environments or small server rooms
etc. If the building code allows. <br>
<br>
Operating theaters for example dont have fresh air injected into
them. It's a highly filtered air that's injected from the outer
rooms surrounding the theater through HEPA and active charcoal.
What counts as fresh air. <br>
<br>
These guys make an interesting device.
<a href="http://altitudetraining.com/prevenex/products/airunit" target="_blank">http://altitudetraining.com/prevenex/products/airunit</a><br>
<br>
Matt.<br>
<br>
<br>
On 13/01/14 7:07 PM, Bevan Slattery wrote:<br>
</div>
<blockquote type="cite">
<div><br>
</div>
<div><br>
</div>
<span>
<div style="border-right:medium none;padding-right:0in;padding-left:0in;padding-top:3pt;text-align:left;font-size:11pt;border-bottom:medium none;font-family:Calibri;border-top:#b5c4df 1pt solid;padding-bottom:0in;border-left:medium none">
<span style="font-weight:bold">From: </span> Tony de Francesco
<<a href="mailto:tonyd@pue.com.au" target="_blank">tonyd@pue.com.au</a>><br>
</div>
<p dir="ltr">> Yes but Inergen is not used in large DCs
because of the volume required.</p>
</span>
<div>Simply not correct. Most large DC’s segregate spaces to
allow full discharge in a specific area.</div>
<span>
<p dir="ltr">> The European system is a hypoxic system at low
pressure. Very different to dumping a whole bunch of gas
through high pressure nozzles.</p>
</span>
<div>Challenge with this system in Australia (which I looked at
early in NEXTDC days) was that in Australia you need to
continually supply fresh air to a DC under the building code.
It is difficult to continually deliver a hypoxic environment
across a large facility considering the Australian standards and
the need to continually extract O2/Inject N2 into the air
supply.</div>
<div><br>
</div>
<div>Hypoxic systems are typically used in things like ship engine
rooms to reduce the risk of catastrophic fire or in environments
with low traffic flow (archives). In a colocation environment
in Australia I couldn’t get an insurer to get their head around
having staff and customers in a facility with a reduced O2, let
alone the technical issues around a requirement to continually
alter the air mix due to the building code.</div>
<div><br>
</div>
<div>So if you want to maintain a lower level of O2 you had to
operate the Agent Generator (essentially lower O2 in a bottle)
24/7 to maintain the O2 levels at the Fire Type 2 levels. The
amount of fresh air required in a 20,000m facility that had a
volumetric size of 100 megalitres is “significant”. Very
significant.</div>
<div><br>
</div>
<div>All in all it wasn’t technically or commercially viable for
NEXTDC at the time to provide a continuous hypoxic environment.
This may have changed. There was some investigation into using
an agent generator to create the refill in case of discharge
removing the need for a refill from alternate gas suppliers.
But the equipment needed to refill 20 megalitres (hall
discharge +1) was significant and the bottles required was
considerably greater from memory. Also not all gas discharge
systems are as high pressure these days so you may want to check
out the latest to ensure your points are valid.</div>
<div><br>
</div>
<div>Cheers</div>
<div><br>
</div>
<div>[b]</div>
<div><br>
</div>
<div><br>
</div>
<span>
<p dir="ltr"><br>
</p>
<p dir="ltr"><br>
</p>
</span>
<br>
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