Author Topic: What price safety  (Read 28368 times)

Offline Mark Sanger

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Re: What price safety
« Reply #15 on: February 22, 2015, 05:03:54 PM »
I would always use a second sheath between the T light and wood.

However there is no regulation ( at least when I checked with H&S/product design safety Gov Dept) a few years ago to state that you have to include a fire proof material between the candle and wood.

This is covered my the product safety act with no specifics for candle holders with it being a cover all regulation.

What the regulations say is that if you inform the customer with a sticker ( do not leave candles unattended, do not let burn down to the wood, do not leave in presence of children of pets etc etc etc) then you are covered.

The lady I spoke to went on to say that if you sell a candle holder without a candle then you do not even have to have a sticker.

If you look in many shops particularly the ones that sell ethnic type items, incense, Buddhas etc you will see loads of candle holders that have candles that fit straight in contact with wood, I have inspected them and many don't even have stickers and these are high street outlets.

I always use a metal or glass holder as I prefer not to test the system.   :)

Offline The Bowler Hatted Turner

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Re: What price safety
« Reply #16 on: February 22, 2015, 05:44:13 PM »
I agree that there is a moral obligation here and like Mark I do not wish to test the system but surely this is part of what being a responsible and professional turner is all about. (I use the word professional as a mark of skill in this context). We have spoken many times about raising standards and this is just a small part of it. By only making items that conform to regulations or in the absence of regulations are made as safe as possible for consumers we are demonstrating a responsibility above those that do otherwise.

andygc

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Re: What price safety
« Reply #17 on: February 23, 2015, 03:57:20 PM »
Spurred to curiosity by this thread, I tried a little experiment. I suspended a very thin, low-quality, tea light case above a tea light with the edge of the case in the hottest part of the flame (the tip, approx 1,000 deg C). The room was free of draughts. 1 hour later there was no sign of any melting, deformation or burning of the aluminium. It was too hot to touch, but as it hadn't melted, no part of it was above 600 deg C. Also, as there was no glow whatsoever, the temperature at the hottest point was less than 525 deg C - the starting temperature of incandescence.

In the real world the flame never touches the cup. The hottest part of the flame is about 1-1.5 cm above the melted wax pool, in free air. You can drip the melted wax onto your finger and although it is a bit painful, it doesn't do any damage. The wax pool does not normally reach the cup, although it might if the flame flickers in a draught, so there is, most of the time, a layer of insulation between the flame and the cup - candle wax. That insulator is itself a heat absorber since its ignition depends on it vapourising, so it absorbs the latent heat of vapourisation from the bottom of the flame. There is no way that the cup of a tea light gets hot enough to ignite wood, polished or not.

The flame is a different matter. It will ignite flammable material which is in or close to the flame. That is, not separated from it by an insulating layer. When all the wax has gone the flame goes out. Quite often the flame goes out before the wax has all gone becasue of the way the wick burns away before the wax pool has all vapourised. I note the comments about reports of tea lights causing fires, but to say that the heat of a normal tea light resting on a flammable surface caused a fire is implausible. You can try resting one on the palm of your hand as it burns down to discover how unlikely that is.

I'm not saying that you shouldn't use glass cups in tea light holders, but criticism of those who don't should be based on science, not anecdote.

Offline The Bowler Hatted Turner

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Re: What price safety
« Reply #18 on: February 23, 2015, 04:52:51 PM »
I stand by my previous posting. There are as many different types of wood as there are turners to turn it. Just think of an ordinary piece of pine, probably under normal conditions it would not catch and burn that quickly but a piece with a little bit of extra pitch is slightly more dangerous. With other woods the more times the holder has supported a lit candle the more dry the wood is likely to be making it easier to catch. The other thing to consider is the different makes of candle, I have 2 bags of tea lights in my workshop and some are 15mm deep the others are only 12. That means that the user could put a shallower cup in a deeper hole, with a little bit of draught and dry wood the conditions are ripe for a catch.
    One last thing to consider, if you put a lit candle into a tent the flame burns up the oxygen and goes out, but before it goes out the flame shoots upwards sometimes to the ridge, now I'm not suggesting this would happen with a tea light for one minute but it does show the unpredicability of candles. Personally I will not take the risk and if I see anyone in a shop about to buy a tea light holder without a sensible barrier I will point it out to them regardless of who made it.

Offline bodrighywood

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Re: What price safety
« Reply #19 on: February 23, 2015, 06:56:22 PM »
Whatever the science I have seen wood charred in candlesticks and t lights and as John said it isn't worth the risk. Science is great in ideal controlled circumstances but we need to make allowance for the unexpected.

Pete
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Offline seventhdevil

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Re: What price safety
« Reply #20 on: February 23, 2015, 07:18:37 PM »
Spurred to curiosity by this thread, I tried a little experiment. I suspended a very thin, low-quality, tea light case above a tea light with the edge of the case in the hottest part of the flame (the tip, approx 1,000 deg C). The room was free of draughts. 1 hour later there was no sign of any melting, deformation or burning of the aluminium. It was too hot to touch, but as it hadn't melted, no part of it was above 600 deg C. Also, as there was no glow whatsoever, the temperature at the hottest point was less than 525 deg C - the starting temperature of incandescence.

In the real world the flame never touches the cup. The hottest part of the flame is about 1-1.5 cm above the melted wax pool, in free air. You can drip the melted wax onto your finger and although it is a bit painful, it doesn't do any damage. The wax pool does not normally reach the cup, although it might if the flame flickers in a draught, so there is, most of the time, a layer of insulation between the flame and the cup - candle wax. That insulator is itself a heat absorber since its ignition depends on it vapourising, so it absorbs the latent heat of vapourisation from the bottom of the flame. There is no way that the cup of a tea light gets hot enough to ignite wood, polished or not.

The flame is a different matter. It will ignite flammable material which is in or close to the flame. That is, not separated from it by an insulating layer. When all the wax has gone the flame goes out. Quite often the flame goes out before the wax has all gone becasue of the way the wick burns away before the wax pool has all vapourised. I note the comments about reports of tea lights causing fires, but to say that the heat of a normal tea light resting on a flammable surface caused a fire is implausible. You can try resting one on the palm of your hand as it burns down to discover how unlikely that is.

I'm not saying that you shouldn't use glass cups in tea light holders, but criticism of those who don't should be based on science, not anecdote.


the tip of that flame can not have been that hot as aluminium melts at around 660c.

strange that it didn't melt as candle flames are supposed to get up to 1400c.

i wonder if the wax in the candle burned at a lower temp?

Offline Les Symonds

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Re: What price safety
« Reply #21 on: February 23, 2015, 07:38:40 PM »
........we need to make allowance for the unexpected.....
Pete
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Education is important, but wood turning is importanter.

Offline Graham

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Re: What price safety
« Reply #22 on: February 23, 2015, 08:11:16 PM »
Who was it that said.....
The whole world is stupid, except me and you.


and I am not to sure about you !!!
Regards
Graham
I have learnt the first rule of woodturning.
The internal diameter should never exceed the external width.
Nor the internal depth, the external height.
Does that make me an expert now ?

Offline The Bowler Hatted Turner

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Re: What price safety
« Reply #23 on: February 23, 2015, 08:32:44 PM »
Ah Graham wasn't that our chap Shakespeare?....I thought he said..."all the world is strange my friend except you and I ..and even thou art a little queer!!" but as eng lit was never my subject I may be wrong.

Offline Graham

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Re: What price safety
« Reply #24 on: February 23, 2015, 08:46:05 PM »
:)
You may well be right John. I think there are several versions now and I wasn't about to tell anyone on here I thought they were queer  :)
Regards
Graham
I have learnt the first rule of woodturning.
The internal diameter should never exceed the external width.
Nor the internal depth, the external height.
Does that make me an expert now ?

Offline Paul Hannaby

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Re: What price safety
« Reply #25 on: February 24, 2015, 11:16:21 AM »
Andygc, I think I would prefer to put my faith in the findings and experience of the fire service rather than your somewhat limited "science". As others have already said, not all tealights are the same so unless you have tested them all in a variety of situations, I don't think you are able to reach any meaningful conclusion.

History has shown that science has a habit of confounding even the best scientists!
« Last Edit: February 24, 2015, 11:19:25 AM by Paul Hannaby »

Offline TONY MALIN

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Re: What price safety
« Reply #26 on: February 24, 2015, 11:40:27 AM »
I use the ones with batteries. Problem solved.

Offline happy amateur

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Re: What price safety
« Reply #27 on: February 24, 2015, 04:37:18 PM »
Ah Graham wasn't that our chap Shakespeare?....I thought he said..."all the world is strange my friend except you and I ..and even thou art a little queer!!" but as eng lit was never my subject I may be wrong.
According to my computer it was Robert Owen

Fred

Offline Graham

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Re: What price safety
« Reply #28 on: February 24, 2015, 05:22:17 PM »
The other one I like is...
 I know the world is full of idiots and I don't mind that, but why do they all gather around me ?
Regards
Graham
I have learnt the first rule of woodturning.
The internal diameter should never exceed the external width.
Nor the internal depth, the external height.
Does that make me an expert now ?

Offline TWiG

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Re: What price safety
« Reply #29 on: February 24, 2015, 07:11:46 PM »
This subject seems to re-appear regularly , ( I do not make candle holders of any sort ) however,  has the fire brigade actually attributed a turned wooden candle holder of any kind with a T -light in it  being responsible for a fire or just  T-lights themselves ,  possibly being placed too close to  flammable materials such as curtains , paper etc ..If the H&S deem T lights being safe by way of the foil cup then I would not criticise any  one selling such items .  Terry..