Underground fireproof bunkers

[GumbyLearner]

I agree with Uncle. You would cook in a shipping container. I worked at QRX for years loading shipping containers for export. In summer all the blokes would lose a ton of weight in body salts from just a day of labour.

I partially agree with Snake. I think Aboriginal people have traditionally managed the land and have for millenia known about the harshness of bush fire in Australia.

As for fire-proof bunkers I really can't give any in-depth knowledge like that posted by Uncle.

But I do know that if a fire-proof bunker was to be constructed on a property, it wouldn't be advisable for anyone to use the old-growth timbers situated next to the water-catchments of Victoria such as the Thompson, Cardinia, Yan Yean or Sylvan dams (All very proximate to where this tragedy has occured) as building materials. I'm sure they would be just as flammable as any other material in a wildfire.

I'm sure if more of an effort was made by the Vic Govt for the last couple of decades, to leave the trees lying next to the catchments in the ground. After all those catchments do need there drop or two of precipitation to maintain life. Then probably Victoria's dwindling water resources, drought and resultant water restrictions would not have resulted in the terrible destruction of the beautiful landscape of Victoria we have seen over the previous week.

The drought is a reality and the worst thing that has been done in Victoria
is to log next to the catchments. I'm no scientist by do remember simple stuff from high school. There is no point to precipitate an event by messing with the precipitation cycle.
http://en.wikipedia.org/wiki/Precipitation_(meteorology)

Just my

 

[Uncle Festivus]

Uncle, since you're in the RFS you might know what fire retardants are available to the public... eg something to add to water.

I use an agricultural wetter and spreader to get better effect from water sprayed on vegetation (mainly grass and undergrowth) immediatly ahead of a fire but have never enquired if there is anything else that we can use.

I suspect that many people wouldn't know a few little tricks to make a little bit of water go a long way to sufficate fires better.

We sometimes use foam additive in 20l drums, but not sure if it's available or cost effective for personal use as you would go through 20l in a few minutes, but it's good stuff. If you do find some make sure it's not AFFF type as it's a bit toxic 3M usually make it.

 

[acouch]

some amazing photos of the victorian bush fires
ac

http://www.boston.com/bigpicture/2009/02/bushfires_in_victoria_australi.html

 

[SevenFX]

As someone mentioned placing the shipping containers away from any falling items and IMO one step further would be to bury the container underground with 2 access doors & air inlets to avoid the extreme heat which may only last few hours till firewall passes..???

Gonna need a big shovel or a dozer, but Lifesaver I'm sure.

SevenFX

 

[awg]

An exposed shipping container would cook you alive, they are bad enough just on hot days. If you buried it you then get rusting?

I would be building a rammed earth house structure, with double glazed (small) windows to minimise exposure to radiant heat, gutter leaf proofing, along with the concrete tank and side building built below ground level or into the side of a hill or behind some sort of earthen wall as above, with the besser blocks filled with concrete, and concrete roofs to both tank & bunker also. I'm in the local RFS so from experience it's all about the radiant heat in the first instance, then it's maintaining the fire rating untill the fire front passes, usually 20 mins or so??

Not only would you have a house with good fire resistance but an excellent energy efficient house too. Perhaps this is what the law will now require?

After I posted this thread for my research, I googled and found another forum, with some details..I should have done that first

I have previously read a bit in Earth Garden and Owner Builder mags on the topic

Basically, the best solutions were along the line of above by Uncle, BUT that COSTS.

ranging down to (cheapest)...dig a muddy ole trench, and use wet woollen blankets. (will save life)

seems intense radiant heat is the usually the main problem, so one must be able to be protected from that for about 15 mins, either below earth or in building that WONT CATCH fire for 30+ mins.

the consensus seems to be that the air is breathable, with some precautions.

Seems preparation and drill are essential, in fireprone areas.

As they are having a Royal Commission, I expect there will be many recommendations along these lines

 

[seasprite]

although expensive , I would be inclined to have a bunker similar to the one that "overit" posted , however it would be out in the open at a radius far enough from the highest tree and the pathway to and from it clear of overhead electrical wires.
Construction would be fully concrete with a bunker inside a bunker , so there is an air gap to prevent heat conduction between walls and roof.

Doors would be offset to each other and have the ability to jettison them from the inside.

contents would include snippets of the above postings as well as a tramping bag with spare clothes/shoes for each member of the family. Torch , first aid kit , heavy duty gloves (fireproof) ,tool kit , water, food and axe .

As mentioned before, I know Liquid oxygen (LOX) is highly combustible in contact with petroleum products (hydrocarbons) ie grease/oil . Filter type respirators or wet towel may help breathing inside the bunker , unsure about scuba gear.

 

[So_Cynical]

I worked as a professional fire fighter with State forests of NSW for 7 years, been to dozens
of fires...i would chose a buryed shipping container over staying in a mud brick house any day.

Was thinking today that a very high percentage of the victims would of died due to poor
decision making, so education to enable some of them to make better decisions maybe
should be compulsory for people living in high danger areas...i remember the 2 day intensive
course we all did was very very good, and certainly gave me the confidence to go to any fire
situation as a very aware, confident and safe fire fighter.

Interesting how in this latest disaster no fire crews were lost at all...first time i remember a
super big fire where no fire fighters were lost or even hurt, i think that the intensive training
has alot to do with that.

 

[Smurf1976]

I recall hearing what I believe to be a true story about someone boiling to death when they took shelter in a water tank during the Tasmanian fire disaster of 1967.

So I'd be careful that if you're building something above ground, it needs to have a huge amount of thermal mass and/or insulation to prevent it heating up. If it's 40 - 45 degrees to start with, the fire won't need to add too much heat into your shelter to kill you.

With 60 or so lives lost and entire towns obliterated, what happened in Tas 42 years (to the day) earlier was an event broadly similar to the Victorian fires just on a smaller scale. Likewise the Ash Wednesday fires in 1983 in Vic / SA were also a massive disaster. There's a lesson there - odds are it's going to happen again sometime so it makes sense to prepare.

 

[noirua]

How much does a fireproof bunker cost? How many would be needed? If 500,000 were needed, how long would it take to make and install them? Who would pay for them?

 

[Uncle Festivus]

How much does a fireproof bunker cost? How many would be needed? If 500,000 were needed, how long would it take to make and install them? Who would pay for them?

The concrete tank mobs have the knowhow already, just need to bury it? It doesn't have to very big either, big enough to last the 20 minutes for the main front to pass over - 5 sq m - like they use on NSW railway for comms huts? Never use pure oxygen, probably use SCBA - 1 cyclinder would last 20 min but expensive.

 

[Happy]

I saw on TV report that material used in napkins and tampons is great fireproofing medium.

It was made into foam-gel, applied externally to building as single use protection, but looked impressive.
Lasted long enough for fire to go past.

Cannot find link now, maybe somebody seen it and has link?

 

[awg]

Something I should have added in the initial post.

In rural areas there is a problem of theft of property for various reasons, including absentee owners.

So making the fireproof bunker double as a security shed for things you dont want pinched, makes economic sense, as well as risk reduction.

So heavy concrete walls, roof even, and heavy steel doors, will stop casual theft ( although nothing stops oxy, as a certain person I know says).

I think the pic of the unit (earlier in the thread), right up against the concrete water tank, seems a good simple design, to save your life.

 

[tubbyt111]

hi the cost of a fire bunker is not inportent.just put the best one in if its going to save your life.as for the shipping containers they will rust over time.
I can put fire bunker in the ground that will not rust not leak .with a fire brick
and fire door entry .has anyone thought of a vent that comes up from the bunker and vents though a bed of small rocks .Dont think this will not happen again it will.that is why im going to put everythink into makeing fire bunkers .
The one and only part i need is how to vent or keep air in the bunker for at least 40 min I think under ground is the way to go. what price do you put on
your wife your kids and yourself just look at the papers dont try to save money If anyone can give me ideas on this vent would be great

 

[seasprite]

If anyone can give me ideas on this vent would be great

that's a tricky one , it is beneficial that you maintain some sort of positive air pressure so that there is a differential inside your bunker to prevent ingress of smoke. If you were to install a vent , I would suggest that you install some sort of valve/tap on it so that you can close the vent should it start causing a negative pressure in the bunker and suck smoke past your door. As uncle festi said self contained breathing aparatus (SCBA)/ respirator would be my personal choice.

 

[overit]

has anyone thought of a vent that comes up from the bunker

No expert here but could you not use some kind of smoke filter over your vent and also have some kind of mask. If you have cleared a suitable area around your bunker exposure should be kept to a minimum one would think.

Also some kind of battery powered extractor fan might be worth looking into to keep the air circulating.

Just some ideas. Make of them what you will.

 

[Happy]

Scuba bottles seem to be safer than pure oxygen bottles to increase oxygen content of air mixture in the bunker.
All you have to do is slightly crack the valve to keep positive pressure in bunker.
Some prior tests can be done to make sure that cracked open bottles last at least an hour.

As added bonus decompressing air would also give some cooling effect, even ice will form on the outlet.

As we breathe in air mixture, there is about 21% Oxygen, 78% Nitrogen, under 1% Argon plus 0.03% CO2, used to be 0.02%, but must have gone up with increased CO2 emissions.

Not 100% sure on my figures, but problem is that our lungs will not pick up oxygen from air if relative oxygen content drops below 16%, absolute minimum 15%, so there is not that much human life supporting useable oxygen in air mixture to start with.

I would imagine some sort of CO2 absorber would be beneficial too.
Removing CO2 from air mixture will also lift up relative % of oxygen content.

Possibly moisture absorber would be good too, as air we breathe out has 100% humidity.

Adult, not breathing heavily will breathe 1.5 to 3 litres of air about 10 to 12 times per minute.
Multiply that by number of adults and children can be counted the same, as scared or crying people seem to breathe more often.
(900 to 2200 litres per hour per person times 5 people makes it up to 10 cubic metres of air per hour)

Too small bunker, filled up with valuables will only provide limited supply of breathable air, so better to have bigger capacity as some unexpected guests might join the survival party.
(Almost funny thought, every person not only uses air, but also displaces some air by being there. Put a lot of people in a small space and all of the sudden you need a lot more air just to survive being there)

 

[Steen7771]

We have been producing Pre-cast underground bunkers for a few months now. It started out as something we did for friends and family. We decided for our own houses it was far easier to simply pre-cast it and drop it in a hole. From there we got about to designing all the necessary features. Air supplies aren't really required, there's ample air for several adults to survive several hours. You need good fire and first aid training, a first aid kit, water, clothes, food etc. Over complicating these things pushes up the cost and families won't be able to do it. You need a good, thick, concrete structure, buried, easy to get in and out of, and large enough to have a bit of air around you. Ours all have the ability to park on top of - which makes them more attractive in the off-times. Quit the hullabaloo - keep them simple, strong and cheap and keep them affordable for families. avoid expensive re-breathers etc. You aren't going to live in it, it's safe haven for an hour. visit our very amateur website if you want to argue this out or get more info. Fire bunkers will save lives, but not if there's years of debate about how to do it! www.fireshelters.com - I do have an interest in this business but only as far as bringing an inexpensive product to the fore before the big boys do and charge double the price.

 

[Steen7771]

Further,

If you build your own, DO NOT VENT IT unless you know what you're doing with one way valves etc. As the fire front passes, most if not all, of your air will be sucked out. Then, like lungs, behind the fire your bunker will inhale - a lot of smoke.

IF the fire sits around your bunker for a bit, your air will be sucked out and stay out. You will be in a lot of trouble.

Make them airtight.

Thankyou.

 

[nunthewiser]

Further,

If you build your own, DO NOT VENT IT unless you know what you're doing with one way valves etc. As the fire front passes, most if not all, of your air will be sucked out. Then, like lungs, behind the fire your bunker will inhale - a lot of smoke.

IF the fire sits around your bunker for a bit, your air will be sucked out and stay out. You will be in a lot of trouble.

Make them airtight.

Thankyou.

and thankyou actually , i never considered that side of it

cheers

 

[Steen7771]

How much does a fireproof bunker cost? How many would be needed? If 500,000 were needed, how long would it take to make and install them? Who would pay for them?

We can make 2 per day, possible 4 if we trippled our staff. They are normally under $5000 but each site is different and each shelter or bunker has custom features, access, etc. eg - we can cast in roll bars around the entry to prevent fallen branches blocking your escape .

A very large one, for say 8 adults, would be just under $8000.

Steen

Be safe everyone.