Classic British Flight Sim

You're right Scorpious and it's Gamma radiation they're worried about ;-)

I very much think it's a case of H&S gone mad but it kinda reflects the 'Nanny' state we live in doesn't it :roll: Zap a counter over the majority of old aircraft instruments and it's 'Bingo' time. Unfortunately, someone found this out and we've ended up in the situation we see now.

I couldn't tell you what state any of my ASI's are in. The Lanc looks pretty cool (though I'm not sure it actually IS off a Lanc as the speed calibration is too high for my liking.. perhaps a Beaufighter). All the calibration lines are still nice and off white. The Hunter ASI maybe a little worse. Although the inner calibrations and numbers are clear as is the needle, the outers have dulled to a dirty cream colour. As for the Wellington.. that's ALL cream/brown :o Ah well.. I'm not gonna get rid of em for the sake of a little radiation. I might get run over by a bus (though that's be exceptionally unlucky given the frequency of buses in this neck of the woods)

ATB

DaveB :tab:

DaveB wrote:

I might get run over by a bus (though that's be exceptionally unlucky given the frequency of buses in this neck of the woods)



DaveB :tab:

You would really have to work at it in my village Dave - one an hour - if they feel like running it.

Graham

We had a fault with our landline some years ago and a BT man, perhaps he was a PO Telephones man, arrived to fix it. For the previous 30 years or so we had used a 'trimphone' which came with the house when we bought it. When the telephone engineer saw it he almost had a stroke! He actually ran out to his van brought back amost official looking container and slammed th etriimphone into it, then back to his van. When he returned he told us that his depot had a large container full of trimphones which were now said to be dangerous from a radioactive point of view. Mid you you did not have to switch a++light on to dial ythe numbers they really did have agreenish glow at night!

In his hands he held abrand new PO approved telephone which he said the company would be pleased to give us at no charge to replace our 'trimphone.' We still have that free phone today although many of our neighbours have dispensed with using landlines preferring the latest mobile. What use telephone directories today?

The Tritium in my traser watch has a half-life of about 12 years. Surely any paint remaining on the dails would be perfectly harmless now considering the age of the thing?

Or were they using something else?

I inherited my Grandfathers watch many years ago, a rather nice Zodiac. Anyway I started wearing it daily as my normal watch had broke, about three years later I was training as an Oilwell Logging Engineer and doing the radiation protection officer course. Part way through the day the instructor handed a Geiger counter around the room, now bearing in mind we were near Aberdeen the background radiation was pretty high, but when it got to me it went off the scale. So we changed the scale. Anyway at the end of that lecture we checked the watch and did a quick exposure calculation which indicated I should see some mild hair loss in the affected area, which I'd just thought was the watch rubbing on my wrist!
Going by the age of the watch it probably uses the same strength paint as the instruments we're talking about, I won't tell H&S it's in a jiffy bag with a couple of radiation stickers at my parent's house.
If you want to find out what you can do with enough Tritium paint try and find a copy of 'The Radioactive Boy Scout' about an American Eagle scout who built a radioactive pile in his parent's back garden.

In the US, all gauges built with radium paint have to be refurbished with modern, non-radium paint prior to being certified for flight as a primary flight instrument. This has some to do with the radioactive issue (an I've run a Geiger over some un-refurbished instruments and it's amazing the count, although not harmful in normal exposure, in an enclosed stale atmosphere, I can see how it might build up to something worrisome). Most gauges made up through the 1970s used Radium instead of the much safer Tritum.

As has been said before, the problem isn't the undisturbed instruments as much as the degredation of the paint that holds the tritium and thus much of the radiation in. We have to remember that when this was a "normal" thing to do, radiation and its effects on humans (much less animals) was very poorly understood, so these things were done in ignorance. One can only imagine how they would have reacted had they known how dangerous it was to use it, much less MAKE the paint.

The difference is staggering. A pocketwatch with a "typical" amount of radium paint gave a dose of 60 mrem per year (although concentrated to the lower body). A pocketwatch with the same amount of tritium paint only gave a dose of ~0.6 mrem per year. An aircraft instrument used about double the amount of paint as a pocketwatch to meet U.K Admiralty luminescence regulations, so that's at least 120 mrem per year (the pocket watch is based on a 16 hour per-day exposure, but consider there's more than 1 radium painted instrument). That's just under half of what a smoker increases his/her exposure per year (280 mrem), and almost a third of the total exposure per year (380 mrem). So, your exposure, while not "life threatening" can make your risk for various radiation-related health issues elevated.

Personally, I would rather be safe than sorry on that issue.

Soucres: http://www.orau.org/ptp/collection/radi ... ntinfo.htm
http://web.princeton.edu/sites/ehs/osra ... ground.htm

Most interesting CT. I shall now steer a wider circle than previous around what is left of XD816 ;-)

ATB

DaveB :tab:

So they used radioactive paint to amke the dials glow in the dark? how come the dials dont glow on my ASI? could it be that the radicactivity has faded (it is from 1951 after all)

It's also possible that at some time it was refurbished (many were) and the radioactive paint removed. By the late 1960's, the dangers of Radium paint was fully understood and they began phasing in the use of Tritium instead, a much safer compound or the radioactive paint was removed all together. Tritium pain has a half life of about 12 years, so it's very possible that it's now faded because the tritium has decayed sufficiently. The radium should be good for 50-60 years of glow, however if contaminated, it can be reduced, so to be safe, I would have it inspected and see if there's any residual radioactivity to be concerned about.

The should have just put tritium gas inside little vials with phosphor and stuck them to the gauge hands like my watch, much safer.

I wonder what the H&S people would make of one of the helicopters that was used to drop sand and lead onto the burning core of Chernoby No 4!