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Author
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Topic: another nitrate question
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Stephen Furley
Film God
Posts: 3059
From: Coulsdon, Croydon, England
Registered: May 2002
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posted 07-23-2007 01:49 PM
quote: Peter Conheim I happen to have a nitrate print of a 1932 melodrama called FALSE FACES, bought on eBay and shipped to me via UPS Ground (!!!!!). I've not projected this - and I won't - but I've hand-inspected all 9 reels. Of the 9, 4 seem nearly perfect, but 5 have decomposition at the tails and the last 20-30 feet are sticky and ruined.
I've seen something very similar to this at theNational Film and Television Archive. In that case the damage was caused by some early plastic cores on which the film had been wound; I don't know what type of plastic they were made of, but I think they were marked Agfa. The effect was very strange, the centre hole was no longer round, but had become a polygon, with curved sides, and the strengthening ribs wer all very distorted. Wooden cores were ok, as were modern polystyrene ones, it was just this type that caused the problem.
quote: Peter Conheim My questions are: is there any truth to the idea that it can SELF ignite? And are the decomposing reels potentially causing damage to the non-decomposing reels via their proximity?
Opinions vary on this one. There was a case some years ago of a fire involving cans of film which had been left in the sun in, I think, a car park. I don't remember the exact details, but is was thought that the high temperatures reached in the cans over a period of time may have led to decomposition, and eventually, spontanious ignition. Several years ago there was a fire at Henerrson's Laboratories in London. There was speculation that the fire could have been started by spontanious ignition of the nitrate film, but I don't think that was ever proven.
Whether of not it can just burst into flames is not really the point. Where are you storing this; do you have it at home? The film certainly will ignite if you apply a flame to it; if you happen to have a perfectly ordinary, otherwise minor, house fire it would be much worse if there happened to be nine reels of nitrate film sitting in the middle of it. What happens if it goes up while you're asleep? The fumes from burning nitrate are pretty nasty; there would be a good chance that you would be overcome by them. Nitrate becomes more unstable as it starts to decompose; and you have several reels which are doing just that. Are your insurane company aware that you are storing nitrate film? Get it to somewhere that has the facilities to store it safely, to evaluate it's condition, and to decide what needs to be done with it.
quote: Peter Conheim The film originally came in a large hexagonal metal cylinder on 1000' reels; I've since put the non-decomposing reels on cores and as a result they won't fit in the can, so they're in a box. The lid on the can is extremely tight and I'd hate for gas/pressure/anything to build up in there so I'm loathe to store any of it in that can. Thoughts or advice?
Film does give of gases, and needs to be able to 'breathe'; it shouldn't be stored in airtight containers. Yes, fumes given off by decomposing film can accelerate the decay or other reels.
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Leo Enticknap
Film God
Posts: 7474
From: Loma Linda, CA
Registered: Jul 2000
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posted 07-25-2007 06:05 PM
quote: Richard May Self-igniting is not likely, but there have been some historical disasters where this has happened.
Sorry to be anal, but AFAIK there have been some historical disasters where this is very strongly suspected to have happened, but no-one has been able to conclusively prove it - only cite some pretty convincing circumstantial evidence.
Reference - James Cummings et al., 'Spontaneous Ignition of Decomposing Cellulose Nitrate Film', JSMPTE vol. 54 (March 1950), p.271-4. Although this study was done 57 years ago and its methodology wasn't exactly comprehensive, I don't know of any work since which has contradicted or added much to it since.
The most convincing circumstantial evidence I've heard is that of the Hendersons laboratory fire in south London in 1992. The fire was proven to have started in a wood and breeze block outhouse in which there was quite simply no source of ignition: there was no mains electricity supply to the building, nothing that could conduct static electricity, no battery-powered appliances in it ... basically nothing that could have ignited the reels inside. But people have tried to make nitrate spontaneously ignite under laboratory conditions and in similar ambient temperatures to those of the suspect incidents before and since, and unless I've missed some recent research, no-one has ever been able to do it.
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