I reckon two people could spend five hours in that bunker with the ventilation shafts fully closed.
But often you’d only be in there for an hour or so. It doesn’t take that long for the worst of a fire front to pass by… also it’s an absolute last resort. What you are supposed to do is evacuate and not be anywhere near the fire.
Your body will naturally start breathing faster as CO2 builds up in the air. I wouldn’t expect that to start to be noticeable until long long after the fire has passed. But yeah, don’t sleep in it overnight (you won’t be able to, you’ll go into full on panic attack mode eventually).
The real risk would be doing something stupid like starting a generator in the bunker. Those burn oxygen but don’t convert it to CO2, which means your body won’t recognise the danger and instead of panicking you’ll feel perfectly fine until you drift off to sleep, then die.
Our body can’t detect a lack of oxygen, instead we detect too much CO2. Definitely want to understand that if you’re going to use an underground bunker.
In the conditions in which you’re jumping into one of these you don’t really want much ventilation - too much heat/smoke, and potentially even the fire burning through some of the oxygen from the contained air. Underground might not be an ideal place to be but IMO it’s likely the best of a set of bad choices if you can’t get out ahead of time - dirt is a pretty good thermal insulator.
Open the air vent, or the port hole (which is just a hole), or open the door a crack, and can spend about two weeks in the bunker as long as you have water with you (which you should).
By then, hopefully someone has reported you missing and the rescue team will clear the fallen tree.
True, I was thinking about all the smoke in the air, but after some time the threat of smoke would go as the fire (at least should have) burnt passed to be safe to open vents.
Sure - but it’s better than being above ground in conditions like this: https://www.youtube.com/watch?v=lUs6iUpa4U4 - watch all the way to the end if you haven’t seen it, really scary stuff. Some of the firefighters evacuated on foot because it was so hot the fire truck started to melt while they were in it — it parts of it had melted when they came back to check the truck after the fire, there were puddles of metal on the road. There’s also footage from a go pro someone setup at their home before leaving, which shows even worse conditions.
I used to live in a fire risk area - one of these bunkers would’ve been great peace of mind. Sometimes you just don’t know if it’s time to evacuate or not, and we were in a valley with only two roads out. When the weather is perfect for fires, there’s never just one fire in the area. Having both our evacuation routes blocked was a very real risk. Some people had homes in a big clearing wiht no tree
I get they are made for short durations but ventilation is all I can think of. not sure I’d want to be underground in that environment
I reckon two people could spend five hours in that bunker with the ventilation shafts fully closed.
But often you’d only be in there for an hour or so. It doesn’t take that long for the worst of a fire front to pass by… also it’s an absolute last resort. What you are supposed to do is evacuate and not be anywhere near the fire.
Your body will naturally start breathing faster as CO2 builds up in the air. I wouldn’t expect that to start to be noticeable until long long after the fire has passed. But yeah, don’t sleep in it overnight (you won’t be able to, you’ll go into full on panic attack mode eventually).
The real risk would be doing something stupid like starting a generator in the bunker. Those burn oxygen but don’t convert it to CO2, which means your body won’t recognise the danger and instead of panicking you’ll feel perfectly fine until you drift off to sleep, then die.
Our body can’t detect a lack of oxygen, instead we detect too much CO2. Definitely want to understand that if you’re going to use an underground bunker.
5 hours is better than I thought, i can see as a last resort in that case it’s better than anywhere else you could shelter
CO2 absorbers is not a high tech thing. It can be useful additions.
In the conditions in which you’re jumping into one of these you don’t really want much ventilation - too much heat/smoke, and potentially even the fire burning through some of the oxygen from the contained air. Underground might not be an ideal place to be but IMO it’s likely the best of a set of bad choices if you can’t get out ahead of time - dirt is a pretty good thermal insulator.
I reckon you would give it a go if it was ‘try it’ vs ‘burn to death’
Also, what would a person do if something fell on top of the entrance? Running out of oxygen and trapped inside, sounds like a really warm coffin.
Open the air vent, or the port hole (which is just a hole), or open the door a crack, and can spend about two weeks in the bunker as long as you have water with you (which you should).
By then, hopefully someone has reported you missing and the rescue team will clear the fallen tree.
True, I was thinking about all the smoke in the air, but after some time the threat of smoke would go as the fire (at least should have) burnt passed to be safe to open vents.
agree. honestly it’s just not the sort of disaster that a bunker is suitable for
Sure - but it’s better than being above ground in conditions like this: https://www.youtube.com/watch?v=lUs6iUpa4U4 - watch all the way to the end if you haven’t seen it, really scary stuff. Some of the firefighters evacuated on foot because it was so hot the fire truck started to melt while they were in it — it parts of it had melted when they came back to check the truck after the fire, there were puddles of metal on the road. There’s also footage from a go pro someone setup at their home before leaving, which shows even worse conditions.
I used to live in a fire risk area - one of these bunkers would’ve been great peace of mind. Sometimes you just don’t know if it’s time to evacuate or not, and we were in a valley with only two roads out. When the weather is perfect for fires, there’s never just one fire in the area. Having both our evacuation routes blocked was a very real risk. Some people had homes in a big clearing wiht no tree
you are right, evacuation routes can be cut leaving not much choice
Probably better than inhaling smoke, but yeah. Some provide oxygen supplies, though.