Radiation risk???

[markbee]

Hello to all!
I had a clear out the other day and found some interesting items. A type xv11a altimeter. A fuel gauge, a radar compass dial (with cracked glass) and a p8 compass with broken glass. I've done some research and read that the luminous paint used on these was hazardous and the p8 compass also has tubes in it containing some not so nice stuff. All the advice i've obtained off the internet just says 'Don't stand too close for too long'. Does anyone know what too close is? 1 ft? 5ft? Also, is there a way to make these 'safe' as i don't want to get rid of them. They're nice pieces!
All advice will be gratefully received.
Thanks in advance.
Mark.

 

[Kingscoy]

Hi,
I know from German instruments that if the instrument is intact that the radiation levels are near to nothing outside the instrument. A very low level of radiation was messured within 1 meter distance for the larger instruments such as the artificial horizon. Further away the levels dropped to 0. If the glass or housing is broken then of course it will be more then nothing but still within legal ranges of health regulations. It will become a different story when you have hundreds of gauges of course. We even had instruments tested from wrecks we have recovered and even then the radiation is within health regulations. To be sure you can put them in a showcase wich will reduse the levels to 0. Remember most of us had similar clocks beside the bed! I have a Me109, P-47 and Spitfire panel and they are tested standing together in a showcase...levels are 0!! As long as you don't take them apart and do strange things with them you will be okay.
Kind regards,
Sander

 

[Shinpachi]

Please read the following story as reference and I am not in a position to guarantee any safety but -

Fewer cares such small radiation after the Fukushima Dai-ichi nuclear incident in my country because, though I will have to check older news again to describe in details but, more and more people in Tokyo have become radiation counter owners since the incident.

One day, a housewife in Tokyo detected stronger radiation, roughly in my memory ten times stronger than the safety level, walking on the road in her neibourhood. It was impossible for her because her location was as far as hundreds kilometers from Fukushima. Authority came to check immediately. They found a metal box under a house floor and there were several sets of radium in glass tubes inside. An old widow was living in the house and her husband was a scientist about sixty years ago. No one knows why he hid the box there but the couple, and probably their children, were living on the box for more than half a century as an ordinary family. The widow is, in my memory, now 92 and healthy.

 

[stona]

I don't have any first hand experience of luminous dials. I was however a chemist once upon a time. I would estimate that close to the glass of an intact radium painted dial instrument you would be able to measure a low level of radiation but I doubt that you'd measure anything though the metal back or even a few centimetres (10-30) from the glass.

I would be wary of a damaged instrument. The dried paint may well powder,particularly given the ability of the emissions of the Radium to damage both the Zinc Sulphide chrystals (which actually do the glowing)and the bonding agent in the paint. Breathing in or otherwise ingesting such particles would be a bad idea.

Is the P8 compass a later instrument? The tubes may be a Borosilicate glass containing Tritium. Given Tritium's short half life and that the emmisions can't penetrate the glass I doubt that there is much risk attached.

Cheers
Steve

Edit. I've just found some figures measured for some WW2 instruments,measured at the glass face. They would suggest that long exposure at very close range would be ill advised. I also read a report from the UK Health and Safety Executive which whilst being very cautious did suggest that fitting a thicker glass to instruments for museum display might be a simple way of reducing any potential hazard to the public.

It has also occured to me that storing such instruments in a confined space might lead to high concentrations of Radon gas in that environment which would surely be more hazardous. Haven't found anything on that on the internet

 

[tyrodtom]

The main hazard of these instruments was in the manufacturing of them. The needles, and other markings were painted by hand, and the daily exposure was very unhealthy.

 

[stona]

The main hazard of these instruments was in the manufacturing of them. The needles, and other markings were painted by hand, and the daily exposure was very unhealthy.

And because the painters ingested the material by routinely "pointing" the brushes between their lips . I've even read accounts of workers painting their teeth!

The most likely hazard today would also be ingestion of radioactive material,something made much more likely when handling a damaged instrument or when opening a previously sealed unit.

It's been a long time since I did any radio chemistry but given the readings I found for WW2 instruments at the glass I wouldn't want to ingest the material giving those emmisions.

Cheers

Steve

 

[evangilder]

My great aunt died of radium poisoning, she painted the dials with radium. They used to put the tip of the brush in their mouth to make the pointed tip sharp. They also painted themselves up and played in the dark with the stuff, that was considered perfectly safe at the time. But the majority of the danger is from ingesting the material, whether by drinking/eating it or by breathing the vapors. If the instrument is intact, the danger is pretty minimal to non-existent when a foot or so away from the item, and even closer for reasonable periods of time is probably safe. Now if you plan on taping it to your head for several weeks, you may have some exposure.

When in doubt, have them checked with a geiger counter or other instrument.

Similarly, some depression era glass that has a yellow tint to it may contain uranium. The way to test the glass is to place it under a black light. If it glows, you have glass with uranium in it. It's probably safe to display, but I wouldn't recommend eating from it. I have a depression area glass plate that I have had for years. I recently tested it with a black light after using it for several years. Fortunately, it is free from uranium.

 

[markbee]

Thank you all for your time, experience and advice.
Steve, i'm pretty sure the P8 compass is an early instrument and the N, S, E, and W pointers or the tubes were painted or filled with radium and zinc sulfide which as you say turns to dust over a period of time. The glass is broken so it is a damaged instrument. I'll have to think about what to do with it!
Once again, thank you all for your input. It's much appreciated!
All the best. Mark.