Re: OT Re: The fires.

Possibly true, though the partial pressure of oxygen at 10,000
feet (lowest altitude where some folk start, after a day or more,
to experience altitude sickness) is the equivalent of 12% (since
the atmos. pressure there is 60% of sea level).

I doubt that problems from low oxygen start at 15%. In a short
duration event, I'd guess more like 8%.

Clifford Heath.

Possibly. AFAIUI, the problem for humans is not the abscence, but the
reduction in oxygen in the air. 21% oxygen is the normal level with some
people suffering breathing problems when it drops as low as 15%.

I suspect a motor would probably just act as if it was choked. Caveat,
they are either broke or working in my limited skills.

I do not know how critical continuous pumping would be when the firefront
is passing. My understanding is that you want to wet down prior and have
a bit of water on the roof and in the gutter to extinguish smaller
embers/burning leaves, burning twigs, etc when they land on the roof.

When the fire front as passed, you would most likely want the sprays to
continue, but also be able to use fire houes firstly on any part of the
house that is alight, then move wider a field to sheds, etc. So
easy restart would be important.

If you have a petrol / diesel / LPG powered generator used for running
a fire fighting pump, wouldnt it be at risk of stopping / misfiring /
losing power,  just when its needed, if the available oxygen is
depleted by fire ? or "choked" from intense smoke ?

Would some sort of "air supply" be practical in this case ?
Just another possible thing to consider in planning a fire protection
system.

How big was the slab? If it collapsed, it sounded like the
supports/walls gave way.

I'm not worried about the changed nature of the slab,but the collapse.
the purpose is to protect life. Replacing the slab as part of
rebuilding seems sensible.

I suspect that air cylinders might be required. TV carried a few comments
from people about difficulty of breathing when the fire was around and
intense fires can deplete available oxygen.

I agree entirely.

I helped out with the cleanup in Cockatoo after the Ash Wed fires.
Behind the place I helped at, just over the crest of the hill and
set into a slight slope was a 2-storey double-brick house which an
engineer had built with a nuclear bunker under the north-east ground
floor, which was a 9" thick reinforced concrete slab on footings each
side weighing nine tonnes.

The slab was collapsed into about eight big sections, and had changed
so you could break off pieces in your hand - it was like Weetbix.
So much for his nuclear shelter.

As they left during the start of the initial firestorm, an aluminium
dingy, unpainted and stored on its side in a cutting (so mostly below
ground level) beside a steel shed, *burst into flame*.

The cement-sheet house below the road was occupied the whole time and
was untouched by the fire. Firestorms are like that, I saw the same
thing in the Adelaide hills where I'd been 3 days after the fires.

The underground bunker or dugout is the only possible thing that can
survive such a fire. They used to have multiple doors, made of wet
hessian, to allow air exchange.

It's time that every house in such an environment was required to
have one within 50 metres. Other defences too, if they're to get
insurance at the same place that other folk shop.

Unfortunately, I believe it was lack of adequate prior preparation. We
love to live in bushland and too many of us take the risk they we will
never have to deal with a bushfire.

If you look at the surviving houses, many of them show no adaption and/or
accessories for dealing with bushfires.

Things such as radiant heat shelds across windows, permanently fitted roof
sprinkler systems, fire houses diesel powered water pumps, proper fire
hoses.

It is clear that there has been fires of varying intensity in different
places. For some of those fires, you would definitely have need an
underground fire cellar, which has not been a prior recommendation. For
others, people have survived the passing of the firefront and then saved
their and neighbours houses with the garden hose and a still working town
water supply. some simply were able to use the house as a shield until the
firefront passed and then exit it, but were unable to save it.

What we have missed this time on the TV is the usal copious scenes of
urban firefighters in their uniform of thongs, shorts and t-shirts, which
raises another requirement of proper clothing and personal safety gear
(boots, smke googles, smoke respirator and gloves.

Then there isthe old issue of moving the lawn and removing fallen bark,
branches and other dead groeth from around the house prior and during
bushfire season.

Thanks, its a very sad time for friends and relatives of those who've died
and those who've lost everything..

Does anyone know why so many people were overwhelmed in their houses?

   Ian, you have my deepest sympathy. This horrific event has deeply
affected everyone directly and indirectly.

   Coles stores in Australia will be donating their profits for next
Friday to the Red Cross bushfire appeal, see
http://www.coles.com.au/about/community/bushfire_appeal/?WT.mc_id=COLES_BushFire
Appeal

How little we can say.
How little we can do.
Now is the time to dig deep, and say silently with our pockets what we have
difficulty saying out loud.

redcross.org.au
salvos.org.au

There was another UK family on the news today who've been touched by the
tragedy, I'm sure the same will be true for many other places in the world
too.

My cousin wasn't actually killed by the fire itself, he collapsed with a
heart attack as he arrived at my aunt's property to help.

My condolences also Ian,

We went through the strain of trying to find out about a nephew and his
family in Upper Plenty, about half way between Kilmore and King Lake. We
spent Christmas day with them.

We found they were at a hall oval, surrounded by fire trucks Sunday
morning. They have lost their house, but at least they are still alive.

Now living with a sister at Baccush Marsh.

My eldest daughter and her family, was living in Strathewen until they
recently returned to Darwin. Most people in the road (Bowden Spur Road)
lost their homes and lives.

I think almost everyone in Australia will find some sort of personal
connection to this tragedy.

Don...

Thanks.

Aunt Irma emigrated when I was very young and only visited England rarely,
I've never met my cousin.

Irma was my mothers closest sister so she is very upset.

 I offer my condolences, Ian.

RIP an aunt and a cousin.