Greenhouse heaters

[Robbi]

i would be very interested to know exactly what qualifications you have yourself cbr6fs as you appear to be able to quote "facts" on an impressive list of subjects.

Purely for clarification and assurance that your "advice" is sound enough and based on scientific fact.

Might even lend some creedence (sp?) to your posts.

 

[rik_uk3]

It does make one wonder how all these people on high altitude climbs, or on polar trips and cooking in small tents and sometimes running stoves for several hours melting snow manage to survive, you'd think reading some of the posts here that they'd be burnt to a crisp on day one.

My first two man Mountain tent had a fold back panel in the sewn in ground sheet so you could set your Primus up and cook, it also had tunnel vents each end. My big Vango tipi is vented at the top and around the base. I have cooked many time in my small Golite Hex 3 or Vango Force Ten and run gas lanterns at the same time but made sure I vented the tent. The chances of me dying from cooking in a small tent I suspect are far far less than getting a bad cut off a knife. I rely on knowledge, experience and common sense though, I guess I'm old fashioned.

With that I'm off to open the kitchen windows as I'm lighting the gas stove and making a Moka pot of coffee.

 

[Big Stu 12]

Who are these people you mention and what qualifications do they have to render them experts?
QUOTE]

I did ask who was most qualified earlier, no one seems to want to answer this.............

 

[ex member pyrophil]

tent size can make a lot of difference but so many bushcrafters go on so much about weight, put a posting up about multifuel stove and your have loads of people going on about how much better there coke cans are and how few grams they are lol so it make me wonder how many carry BIG tents.
If is not that windy its not colder outside than inside, talking about were most bushcrafters go. If the weather is bad i use my stove just outside the door.
seen plenty of people use stove in a tent on tv, good program about going to the south pole. That is so cold and the wind chill would kill you if you were sitting around for ages outside. just going somewere really cold is a high risk alone, making cooking outside a higher risk.

 

[rik_uk3]

Safe and sensible setup, stove starts around 2:50 using my favourite Trangia setup too

[video=youtube;sMz0aMaAUiE]http://www.youtube.com/watch?v=sMz0aMaAUiE[/video]

Great looking tent too.

 

[bigroomboy]

I've seen that video many times before and love it rik. I have an exped andromeda which I think is also an excellent tent.

The people I quoted earlier are Ray Mears in his video I posted and Cody Lundin's book when all hell breaks loose. Both recognized world wide as bushcraft and survival experts, I think I will take my information form them before some bloke on a forum.

What would be the point of the proposed experiment? The time it takes a candle to go out would easily be changed by modifying the size of the container, a tent is not a sealed system, if yours is get a better one, without putting a CO monitor in the vessel there is no way to know what the CO content is.

A much better experiment would be for me to set up my 4 season tent in my garden with a candle lit and my CO monitor in hand. Unfortunately I'm not at home and cant do that at the moment.

I think people will be able to form their own opinion from the information in the thread.

 

[bilmo-p5]

The op was talking in particular about candles, my post was in direct response to this.

The basic principles of the safe management of naked flames within tents are the same however the flame is generated

As such there is a vast difference between having candle in a tent to cooking in a tent.

Not really, if you think about it.

With a candle your likely relaxing, reading snoozing etc.

All the more reason to ensure that the siting and ventilation requirements of your candle are met. If there is a chance you will 'nod off' you should be able to do so reasonably safe in the knowledge that your candle is not going to gas you or burn your tent down around you before it burns out. Personally, I think it is sharp practice to risk snoozing with any form of naked flame burning and would much rather risk running down a set of head torch batteries.

When cooking you will have bell doors open, your attention on the job in hand and your hands free to toss the stove out if something happens.

How you achieve the ventilation your stove requires depends largely on your tent and doesn't automatically require the doors to be open. If you need to toss the stove out in the event of some mishap, your 'flame management' is already a total fail. You should have the means to extinguish say, a fireballing stove, to hand so that you can killthe flames in situ without needing to risk injury and damage by moving it. It needn't be much; a damp dish- or hand-towel is sufficient. It will successfully extinguish a chip pan full of boiling burning fat in short order, so a recalcitrant Coleman shouldn't be a problem.

Even when cooking there are different risks associated with different fuelled stoves that people need to be aware of, igniting a gas stove can cause flare up's, you need to be careful of spillage when lighting a meths burner etc etc.

"Given a good working knowledge of one's equipment, including its shortfalls and hazards, the exercise of a little common sense and a good deal of care, there is no reason why a naked flame appliance such as a camp stove should not be safely used in all but the tiniest of synthetic tents."

While i'm at it, there is also a vast difference between cooking in a teepee style tent to cooking in a tiny 1 or 2 man tent and different risks associated with either.

It's primarily an available space issue. Beyond that, it boils down (excuse me) to the individual's choice and use of equipment.

If someone is using a candle for heat then it seems pretty obvious to me that they are not going to have the tent doors wide open.

No reason why they should if they can adequately ventilate the space without doing so

They're also going to be tucked up in their sleeping bag,...

If they still need a candle for warmth when they're tucked up in their sleeping bag, they're peeing into the wind and need to seriously review their choice of bag.

... so more ready to snooze than for a quick exit.
If they do snooze they then run the risk of knocking over the candle in their sleep.

Leaving a candle burning when there's a likelihood of falling asleep is bad enough. Leaving it somewhere where it might get knocked over is inexcusable.

Do you see the difference?

No, because other than the size of the flame, there isn't any.

The basic principles of the safe management of naked flames within tents are the same however the flame is generated

 

[ex member pyrophil]

nice vid rik, -14 chilly lol yeah if i was there with that size tent i would of done the same.
in cold conditions, were you are, what you have, how cold ect its putting the risks in order.

 

[ateallthepies]

I'm glad this thread has come up, Co poisoning has been of interest to me since I have started getting into Paraffin fuelled heaters and lamps. I often wonder how most people pre central heating/electric lighting dealt with this issue, maybe houses were inherently draughtier?

This sad case of the girl killed in the tent.... http://www.dailymail.co.uk/news/art...Harris-poisoned-BBQ-New-Forest-Hampshire.html

I suspect that barbeque was pumping out much more Co than any well maintained gas, petrol or Paraffin appliance could achieve? The thing that worries me is that there seems to be plenty of ventilation around the outer skin at the bottom of the tent? So maybe ventilation isn't enough and some actual air movement is needed to purge the Co?

Steve.

 

[rik_uk3]

Charcoal is just about the worst thing you can burn in terms of fumes I believe, thats one I'd never use indoors including a tent because you realistically have no control over the burn. After Katrina there were quite a few deaths caused by people bringing charcoal BBQ's indoors....fumes, poor ventilation = death. Know your kit, make sure you have a good air flow and = warm camper

 

[cbr6fs]

Charcoal is just about the worst thing you can burn in terms of fumes I believe, thats one I'd never use indoors including a tent because you realistically have no control over the burn. After Katrina there were quite a few deaths caused by people bringing charcoal BBQ's indoors....fumes, poor ventilation = death. Know your kit, make sure you have a good air flow and = warm camper

Again it's not the fumes, they died specifically of CO poisoning.


I am not going to bother answering the nit picking and bickering posts, i think Blimo has made some good points and my opinion is clear i believe.

I have cooked in a tent and chances are i will again, i do take precautions though and i do feel strongly that if we are advising people it's ok to cook in a tent then it's imperative that these precautions are made 100% clear.

With regards to having a candle or heat source in the tent.
Tents specifically designed for this purpose (teepee etc) aside i can't see any point in having a lit candle in atent.
It's heat output is insignificant and in this day and age torches last forever and are a LOT safer if it's illumination you want.
For me the risks simply do not outweigh any sort of usefulness.

For other heat sources again with modern materials i really don't see the point in the UK.
I've camped out in conditions where my urine disposal bag was frozen solid in the morning yet i was toasty warm all night tucked up in my sleeping bag.

I can see the draw of older simpler ways of doing things, but if this floats your boat your better off having a tarp or natural shelter next to a fire with a back block to focus the heat towards you.

I just can't envisage a case where i would risk having a open flame in my tent purely for heat generation, even if it keeps you warm for 30 mins or so only a fool would sleep with it lit so it offers no advantage during the night.


I didn't really want to get into all this bickering my intention was to clear up on some inaccurate posts and confusion.
I've made my points clear and i think it's obvious that i err on the side of caution.

The other side is this:

well you're still alive so is that not enough proof, did you feel ill?

If your adult you make your own risk assessment, if your a minor then please please please speak with someone face to face that knows what they are talking about before risking your life.

 

[bilmo-p5]

If your adult you make your own risk assessment, if your a minor then please please please speak with someone face to face that knows what they are talking about before risking your life.

Sound advice.

 

[rik_uk3]

Sound advice.

What he said lol

 

[Doc]

Thought I’d look at this from a scientific viewpoint. It’s a long time since I did A level chemistry….


I estimate my tent contains about 3 cubic metres of air. That’s a mass of about 5kg of air.

A tealight candle has a mass of 10g. Assuming paraffin wax is something like C30H62, roughly 9g of that is carbon.

The sticky bit is I have no idea how much of that carbon will be converted to CO2 (likely most of it), and how much to CO. It will obviously depend on ventilation and the pO2 of the surrounding air.

Just suppose all the carbon reacts to form CO. That 9g of carbon will produce roughly 25g of CO, which will diffuse in our 5000g of air. That would equate to 5 000 ppm by mass (and something similar by volume, as the density of CO is so similar to that of air). Inhaling 1000 ppm for a few hours would likely make you unconscious or worse, and even 100ppm could make you pretty ill.

However, in real life the majority of the wax will combust to CO2, not CO. This scientific article: http://fire.nist.gov/bfrlpubs/fire05/PDF/f05141.pdf suggests combustion is nearly complete, at least in the candles they studied. But in the absence of robust evidence of the CO production of candles inside tents I don’t think I would advocate using candles in a tent with a closed door.

Will it keep you warm? Paraffin wax has an energy density of 43kJ/g, so there’s 430 kJ in our 10g tealight, which is released over 4 hours, or 14 400 seconds. That translates to about 30 J/sec or 30 watts. As most electric heaters are at least a kilowatt, I doubt it would do much to keep you warm!

 

[cbr6fs]

Fantastic post Doc

As i said in a earlier post, if folks are interested in seeing exactly how much oxygen a candle consumes then place on inside a 1 litre sealed container and see how long it lasts, i think people will be surprised how quickly even a small flame will consume the air.

It gets even worse though as when that candle goes out it means there is not enough oxygen left in the container to sustain the flame, the CO readings will be off the scale longggggggggg before that.

If the candle lasts 1 min then you have to factor that the environment would deadly at around 20 seconds.


Obviously a tent is not a hermetically sealed environment BUT it does show just how much air throughput you need to be safe.


I'm not saying that every time someone has a naked flame in their tent they are going to die, obviously that is not the case.
I'm simply saying that people need to know the facts, and not get confused with CO2, CO and the candles going out before you die rubbish.

Some people will read this and make their own risk assessment and continue or try a heater in a tent, others will, like me figure even if it's 1 in a million chance the gains simply don't offset the risks, each to their own.

People do need the facts though to make a calculate judgement, and that has been my goal from my first post to try and clarify the facts rather than letting people try it and see if they're still alive after.

 

[ex member pyrophil]

some people could take one of these with them

 

[rik_uk3]

This

will be heating

next trip and I won't die.

 

[bigroomboy]

cbr6fs, you continue to shout out your "Facts" however at no point have you provided any evidence, only opinion. I have provided evidence and references to counter your highly vocal claims yet you choose to ignore them.

The heat pal rik will be using is designed for heating small spaces such as boats and tents and I have never head any problems with people using them who know what they are doing.

I wouldn't mind your opinion if you were not so forceful in trying to convince people of your opinion by packaging it as fact and you insistance at insulting people (mainly me) in your posts for no reason.

One last repeat of key information. It is common advice to use a candle in a snow cave etc to provide light, heat and and indication your air vent is blocked. Please watch the video I posted on page 2 for this advice straight from Ray Mears.

 

[Nice65]

cbr6fs, you continue to shout out your "Facts" however at no point have you provided any evidence, only opinion. I have provided evidence and references to counter your highly vocal claims yet you choose to ignore them.

The heat pal rik will be using is designed for heating small spaces such as boats and tents and I have never head any problems with people using them who know what they are doing.

I wouldn't mind your opinion if you were not so forceful in trying to convince people of your opinion by packaging it as fact and you insistance at insulting people (mainly me) in your posts for no reason.

One last repeat of key information. It is common advice to use a candle in a snow cave etc to provide light, heat and and indication your air vent is blocked. Please watch the video I posted on page 2 for this advice straight from Ray Mears.

You should read the Methanol thread on BB

 

[rik_uk3]

I've read it, does my head in to be honest, the way people talk you'd think methanol was on a par with Uranium, utter tosh. I'll be using methanol in the Heatpal and I have absolutely zero, nada, not one worry about doing so; I won't drink it, won't wash in it, just burn it.

A familiar name over there spouting off the same as here, like a