Reply With QuoteAny examples of watches containing radium?
I was talking to a leading radiological chemist yesterday, and mentioned radium lumed watch dials. I asked him were they a health hazard.
Whether still luminous or not, they will still be very radioactive, and quite a threat to health if the crystals got broken.
He mentioned old aircraft lumed cockpit instrument dials from WW11 planes that were burnt on a Scottish beach, and at the concern there was over the radioactive material on that beach.
He was adamant that old radium lumed watches should not be worn constantly, that they should be taken off at bedtime, and it was wiser not to wear them on the inside of the wrist as some people like to do.
He was quite serious about it, and said the problem was not best ignored!!!
Here is a link about the beach in question and the dangers posed by radium whether on watch dials or old aircraft instrument dials.
http://news.bbc.co.uk/1/hi/scotland/4610440.stm
I wont be filed, stamped, indexed, briefed, debriefed, I am not a number, I am a free man, my life is my own!!!
Be seeing you
Toodle pip
Griff.
Any examples of watches containing radium?
Use of radium in watches was apparently stopped in the 1950s.
http://en.wikipedia.org/wiki/Radium
Thought the bit about spas was an eye-opener :shock:
I have several vintage watches containing radium.
I would never advice anybody to wear them every day, but that's more because of their age, parts availability etc. etc.
How would you tell if there was radium used on the dial of a vintage watch.
Was there any system to mark the dial, or do we assume pre 50's watches have radium?
Martin
Is the effect cumulative? If I wear my Smiths Deluxe while taking photo's with an old camera with its rare earth (thalium dioxide) lens am I doubling the risk?
Watch out for Timex.
http://alanwatch.homestead.com/radiumtimex.html
Eddie
Whole chunks of my life come under the heading "it seemed like a good idea at the time".
I would assume any watch from 50s or earlier that is or was once luminous did use radium, unless there's an indication that it used tritium - a T<25 symbol or T on the dial somewhere. Tritium dials always seem to be indicated as such in my not-very-extensive experience.Originally Posted by Page
I'm no expert mind you.
Alternatively, get a Geiger counter.
Tritium wasn't used in the fifties. It's a fairly recent material (out of use since the late 90's).I would assume any watch from 50s or earlier that is or was once luminous did use radium, unless there's an indication that it used tritium - a T<25 symbol or T on the dial somewhere. Tritium dials always seem to be indicated as such in my not-very-extensive experience.
I'm no expert mind you.
Alternatively, get a Geiger counter.
My collection of compasses are all full of radium .....and the aircraft instruments that I've got. I've also got 200 tritium tubes sitting in front of me....
Ho hum !!
When did it come into use, do you know? I would guess 60s, but no idea really.Tritium wasn't used in the fifties. It's a fairly recent material (out of use since the late 90's).I would assume any watch from 50s or earlier that is or was once luminous did use radium, unless there's an indication that it used tritium - a T<25 symbol or T on the dial somewhere. Tritium dials always seem to be indicated as such in my not-very-extensive experience.
I'm no expert mind you.
Alternatively, get a Geiger counter.
Seems a shame in some ways that proper radioluminescent materials like tritium have been replaced by phosphorescent ones that need charging. Although I suppose radiation isn't too smashing, and there is the GTLS option.
Tritium is still in use although in the glass tubes that you find in the Traser watches etc ....
http://www.mbmicrotec.com/html/engl/...rigalight.html
Radium did get used in the sixties. Every now and again, you find a watch with "Ra SWISS Ra" on the dial.
That is correct, but it cannot be compared to the way tritium was used before, in a luminescent paint on watch dials.
I do not know when tritium was first used, but I would guess it was indeed in the 60's
I watched a TV program some years ago and it was outlining the deaths of the factory workers ( mainly women ) who used to hand paint the radium onto watch dials, no health and safety precations at all and the majority used to lick the painbrushes to get a fine tip, needless to say hundreds of them died from oral and throat cancer and many had miscarriages and children born with very bad deformities.
Very sad . :cry:
A full length documentary ... http://www.youtube.com/watch?v=zLS6N...layer_embedded
Interesting article by somebody who knows watches and radiation:
http://www.vintagewatchstraps.com/luminous.htm
If I had a 50s or 60s watch in my possession, I'd be finding out if it had a radium dial. If it did, I'd be thinking twice about wearing it regularly.
The main risk comes if the dial gets exposed, either by breaking the crystal, or of you open it up to work on it. Old watches will be full of dust where the lume has crumbled. That means you will be breathing in and ingesting radioactive material, and that is a very bad idea.
Promethium was used in the 60s for a while after radium was banned and before tritium was used. Look for 'Pm' on the dial. I had a few old Roamers with Pm dials that would click away on a radiation detector.
I had my say on Radium: here (post #32).
And here's a bit of info and history about Radioluminescent Paint.
Then there's: Everything you wanted to know about lume, and a bit more.
There is more on TZ if you care to search for it!
For what it's worth, I posted some comments about the radiation output of a particular watch here: http://forum.tz-uk.com/showthread.ph...=1#post2846629 (also links to earlier comments).
Maybe this Ingersol Radiolite is older than I thought.
The name strongly suggests that the lume is Radium.
I've found two papers that are relevant. One that's available online from 2007, and another from 2012 that's only available as an abstract online, although you can buy the paper for $39.95 and download it. The first is:
Radium Timepiece Dose Modeling was prepared for the US Nuclear Regulatory Commission (link)
On page vii, there is a summary of results and the first two of these may interest you:
"The shallow-dose equivalent calculated to the skin is 1,600 millirem per year (mrem/yr)."
This is a dose to the skin, not the whole body (in radiation protection the skin is one of the body's organs that is not the most sensitive to radiation).
1600 millirem (mrem) = 1.6 rem = 16 millisievert (mSv)
"The effective dose equivalent calculated is: 61 mrem/yr for a person who wears a Ra-226 wristwatch, 110 mrem/yr for a person who wears a Ra-226 pocket watch in a pants pocket, and 480 mrem/yr for a person who wears a Ra-226 pocket watch in a vest pocket."
These are whole body equivalent doses that may be compared to the levels of background radiation and limits that are often quoted.
If you're interested in old instruments (historic aircraft etc) then there is a supplement:
Radium Gauge Dose Modeling (link)
As those are US publications they record doses in 'rem' rather than the SI unit, the 'sievert'. This page: link will help you with the conversion. Also:
1 millirem (mrem) = 10 microsievert (μSv)
100 millirem (mrem) = 1 millisievert (mSv)
The second paper is:
Radium dial watches, a potentially hazardous legacy?
The abstract concludes: "The risk from old watches containing radium appears to have been largely forgotten today. This paper indicates a health risk, particular to collectors, but with knowledge and appropriate precautions the potential risks can be reduced."
You may also find these useful:
Thanks for those links and refs. Most informative.
I was going to say that they are most illuminating but that would just be a terrible pun.
Hmm. I wear some vintage watches on a daily basis that I now (thanks to this thread) believe to have radium hands and markers.
I've considered putting a thin piece of lead foil "inside" my NATO strap -- i.e. between the two strips behind the watch -- and fixing it in place to block the gamma rays; is that unnecessary and a bit paranoid? Or a simple and sensible precaution?
What do we think?
When ever I have worked on any of these old watche's I always make sure I have a fag going , it takes away the stress of worrying about the radio active content
I don't want to worry you, but:
Tobacco Smoke
While cigarette smoke is not an obvious source of radiation exposure, it contains small amounts of radioactive materials which smokers bring into their lungs as they inhale. The radioactive particles lodge in lung tissue and over time contribute a huge radiation dose. Radioactivity may be one of the key factors in lung cancer among smokers.
Gamma rays can probably penetrate a thin piece of lead foil, although obviously it will have an attenuating effect. However, as per my comments here, the dose you get through the case back is only a part of the story.
First of all, the dose you receive through the case base will be against your wrist, which is not the most critical spot in terms of radiation damage. Secondly, the dose will already be attenuated due to the radiation having to pass through the movement and metal case back to reach your wrist (although still see my linked comments for how much this level of radiation could be). Thirdly and most importantly, the dose you receive through the front of the watch when it is facing your body or head is more difficult to account for, and this route is much less shielded by metal! The head and body are more critical locations for radiation exposure.
Personally I'd be more worried about the dose through the front of the watch against the head and body than through the back of the watch against the wrist. There is also the issue of exposure to people around you while you wear the watch and the issue of exposure to you and others whilst the watch is stored.
As per my comments and my earlier linked messages, the radiation from a radium dialled watch is unlikely to be immediately harmful to one's health but it is nevertheless more than I personally would be willing to accept on a daily basis, lead foil or no lead foil. I simply would not wear radium dialled watches on a regular basis. In the long term I think it would be unwise (regardless of a little extra shielding with some lead foil) to do so. As I said before, however, I'd still be willing to own and occasionally wear radium dialled watches but prolonged exposure by daily wearing would be too close to being risky for my liking. As I mentioned above, exposure whilst in storage is an issue to consider too if the watches are stored anywhere near people and not in a more heavily shielded container.
It's very difficult to quantify the risk but if you read my earlier linked comments and all the other links provided here then I think you can draw your own qualitative (but reasonably informed) estimate of the risk.
I wouldn't bother. The penetrating radiation (γ-ray) is already being attenuated by the body of the watch and the skin dose isn't too much of a problem in any case.
I'm reviving this thread, because there have been a few threads recently with members sharing their purchase of vintage military/pilots watches with (lovely looking) radium dials.
I don't want to spoil their threads with a post which might be interpreted as "hey nice watch... might give you cancer!", and obviously it is entirely up to each individual to form their own view of any risks, and decide for themselves what, if any, precautions they take.
However, I am always curious to discuss with people who collect vintage watches with radium dials what their thought process is, and what steps they go through.
When you buy a vintage watch, do you consider whether or not it has/had a radium dial? Do some of you even check (Geiger counters can be bought relatively inexpensively now)? Have any of you bought radium dialled watches without realising or considering that there might be any risk?
When you end up with one in your possession, how much consideration do you give to it? Do you limit wearing it to short periods of time? What precautions do you take when/if you open the case?
I'm very interested in this, and I've done a lot of reading around it.
My personal, perhaps over-cautious approach would be that I would not have a problem with owning one, but I would not wear it. Not so much because of the exposure to gamma radiation through the case or crystal, which could be significant enough to be worth avoiding over time in itself, but because of the increased risk of disturbing and breathing in particles of radium dust (or its fission products, a film or dust of which will likely be spread throughout the movement and case). Internal contamination from breathing in or ingesting this dust is where the real risk lies. With that in mind, I would not be opening any watches with radium dials. I'd also be hesitant about owning one if the case didn't seal air-tight. I'd also take extra precautions posting such a watch, as I'd feel pretty bad if the crystal cracked, and I had to worry about some poor bugger down at the sorting office getting a nose full of radium dust.
What is your view. I'm expecting I'm going to be at the cautious end of the scale, but views will run from people who wouldn't touch them at all, through to people who dismiss the notion of risk entirely, and like, lick the radium off the hands and stuff...
From my reading, the gamma dose through the case varies, but could be equivalent to a wrist X-Ray over 24 hours. So if you're wearing it every day...
A doctor would be very reluctant to expose you to that much radiation.
That's interesting...if it's true. Can you supply a reference, please?
I can't remember where I read that actually, but here:
http://rolexblog.blogspot.co.uk/2009...-of-rolex.html
There is a picture which Mark linked to earlier in this thread showing a reading of 13.73 µSv/h (micro-Sieverts per hour) through the metal caseback of an old panerai. Over 24 hours that's 165 µSv, or 0.17 mSv. The estimated dose from a wrist X-Ray is only 0.06 mSv (http://hps.org/physicians/documents/...Procedures.pdf) so in the case of this particular watch, wearing it for 24 hours would actually be equivalent to nearly three wrist X-Rays.
Even more worrying is the reading through the crystal in the link above: 37.53 µSv/h. If you're wearing a watch, different parts of your body will be exposed to gamma radiation emitted through the crystal, as well as the constant dose through the back on the wrist.
As I say though, my main concern would still be ingesting or inhaling particles of radioactive dust, rather than to gamma radiation through the case.
My maths, or my understanding of the units involved could be out. I'm a layman.
Last edited by seikokiller; 29th November 2015 at 13:29.
Speaking of exposure through the crystal I recall reading some archive material which stated that this was a significant risk for people who slept with their watch on and with their wrist over their eyes. Although this may have been referring specifically to strontium 90 on dials.
I sleep with my watch on, and sleep on my front. I often tuck my left hand under my pillow, so would be beaming 0.04 mSv/h up into my ear in the case of that old panerai.
The archive story
https://news.google.com/newspapers?n...,2980602&hl=en
Is your watch Radium luminised ?
I don't think I'd want to wear any Ra luminised watch in bed. Especially one that is heavily luminised like that old Panerai.
What I will say is that the Effective Dose quoted in the article you linked about X-ray doses from medical procedures will be the whole-body dose rather than the local dose to the wrist or limb (for which the tolerable levels will be higher). If you review the list of doses you'll see that the procedures for the trunk, especially away from the air-filled lungs) are considerably greater. This is for two reasons: a higher exposure will be needed to get a decent exposure through more tissue; and the organs exposed are more radio-sensitive than the limbs and extremities. The Sievert, as a dose of radiation equivalent dose, takes into account the sensitivity of the exposed organs to the absorbed does (see BBC Bitesize: Dosimetry and safety).
The best info I could find was linked in my post #22 above.
You're not wrong, but it is a bit more complicated...see post #32 in another thread.
Ah I get it. Thanks for the clarification.
So the dose from gamma radiation associated with wearing the watch might not be significantly above background radiation.
I still wouldn't though, for all the other reasons discussed. Wearing the watch means you will constantly be disturbing the radioactive dust contained within (both the radium paint itself, and the fission products from the radon gas it produces, which will be dispersed throughout the watch.
Even if you never open it up, old watches are not necessarily air-tight, and I don't think it's unreasonable to suggest that stuff could find its way out of the watch, onto your skin, clothing, and ultimately into you.
Then obviously, by wearing it, you massively increase the risk of breaking the crystal.
If I had one, I'd keep it in the box.
I wonder how many people on this thread living in abject terror of old luminous watches are smokers or are happy to lie frying in the sun?
The other thing I've heard people say is that people wore these for decades with no ill effects.
While that's true, it doesn't really mean anything.
For a start, a radium dialled watch was much safer when it was new, because the paint was stable. Old lume is crumbly, flaky. It breaks off into conveniently inhalable sized chunks in a way it wouldn't have 50 years ago, and with a 1600 year half-life, that 50 year interval has done little to mitigate the damage internal contamination would do.
Secondly, radiation doesn't work that way. It doesn't "give you" cancer. It just gradually increases the risk of getting cancer the more you are exposed to. So it is usually impossible in individual cases to say whether somebodies cancer was or was not caused by radiation. Maybe somembody got lung cancer from radium dust in their lungs. Maybe they were going to get it anyway. Or maybe they were, but not for another 10 years. If they can't determine whether or not Chernobyl has caused a statistically significant number of deaths, it's not going to be possible with something like this.
But that's not a good reason to up and move into the exclusion zone.
Or live in London, where just breathing the air kills more people each year than smoking...
Ach, it's all bluster - everyone knows that diesel is cleaner than horrid old petrol. The Government and the carmakers all said so!
...but what do I know; I don't even like watches!
I can't say I've ever met anyone in abject terror of an old luminous watch. I have however: handled many a radium luminised bit of kit, including watches; monitored the areas where the radioactive material decay products from Radium have plated out inside display cabinets etc; lived in a house that had an asbestos roof on the garage; worked in buildings known to contain blue asbestos; smoked for 10 years; ridden motorcycles; stroked a lion; found myself underneath an inverted raft in a Zambezi rapid...all of which carry a level of risk that I found tolerable.
Radium, like asbestos, is a particularly pernicious substance that needs careful handling. Both Radium and asbestos have useful properties that, in the past, found practical application. Both can still be found if you look for them. Left alone and properly managed the risks should be minimal. Even if the worst happens and I were to ingest/inhale some there's a fair chance that the effect would be nil or negligible. At my age the latency for cancer means that I'd probably die from another cause first. But if I've managed to ingest/inhale it then the genie is out of the bottle, as they say and someone else will have to clear it up/contain it. That exposes someone else to an additional risk...and therein lies a problem.
Good grief, on top of all things now I have radium to worry about. Where is my tin hat?
Next to your sunglasses...link?
Ha ha I think they just banned it under Geneva convention
I think some people have got their millisieverts and their microsieverts mixed up. The radiation from a radium-dialled watch will do you no harm whatsoever, or at least, nothing comparable to smoking, or living in Cornwall.
The danger, which is real, is of ingesting contaminated material if the watch is damaged, or if you open it up to repair it. Even then, so long as you don't start licking the dial, you're probably OK: just be very careful about inhaling or spreading the dust.
If you keep the watch closed, you've nothing to worry about.
Does releasing the crown to adjust the time etc constitute opening the watch as water can get in through an open crown.
Does that include Gillmore, Crockett, Denman, Flowers and Harris? Link:
"A phantom experiment using a TLD suggested an effective dose equivalent of 2.2 mSv/y from a 1 μCi (37 kBq) radium dial worn for 16 h/day throughout the year (dose rate 0.375 μSv h−1). For this condition we estimated maximum skin dose for our pocket watches as 16 mSv per year, with effective doses of 5.1 mSv and 1.169 mSv when worn in vest and trouser pockets respectively. This assumes exposure from the back of the watch which is generally around 60-67% of that from the front. The maximum skin dose from a wristwatch was 14 mSv, with 4.2 mSv effective dose in vest pocket."
That sounds believable. Normal background radiation dose is about 2mSv/yr in the UK, and about 7 in Finland. So wearing a radium dial watch is somewhat less dangerous, in radiation terms, than moving to Finland.
Yep...all things are relative, as they say.
As I've posted elsewhere, an intact Ra lumunised watch isn't much of a hazard. Until, that is, you need to open it for servicing. Then the hazard increases greatly and has the potential to affect more people. The MOD spent a lot of our money replacing and getting rid of its Ra luminised equipment. They did it, IMO, for a very good reason...Ra is nasty stuff. I wouldn't want it in the same house as any children...there are plenty of other good looking watches without any Ra attached (or floating about).
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