Are vacuum tubes/valves radioactive?

yes, the 12ax7a in my phono stage gave me mutant powers. i can now convert ordinary plant and animal matter into a disgusting brown substance that I've yet to discover a use for.

research continues....
 
I sold some military type giant tubes years ago that had "hot" glass blobs in the top section.

I've forgotten the number.

The buyer wanted them only if they were the "hot" type.

Collectors for anything out there.
 
Eimac had the uranium glass pass thru collars on their VHF transmitting tubes.

(in Australian accent) (Holds up KT88) That's not an output tube. (Holds up Eimac 4-400) This is an output tube.

Those transmitters tubes work on sufficiently high voltage (10 kV to 20 kV) to generate x-rays. Not quite the radiation the OP referenced, but close enough.

Tubelab built one that ran on 2 kV or so. Lethal voltage. Death by misadventure lethal.
 
Lethal voltage. Death by misadventure lethal.

I just don't get this lethal codwallop.
Lightning is only lethal, (and there not every time) if it strikes you.

High voltages are only lethal if you happen to slam a large current from one side of your body to the other through the heart area, and even then NOT ALWAYS....usually by sticking your stupid finger somewhere you shouldn't!

You routinely get on metros, electric trains where power lines above or below have voltages anything between 630V DC and 23Kv AC, yet I don't see everyone swooning or dying.

Somehow the mere fact a potential difference exists of up to 1KV DC seems to make the tube audio brigade pronounce "shock horror" and a cult of the extraordinarily dangerous.
This is just getting STUPID.

Can people just get over it, and realise ionising radiation exists everywhere you go.
Fukujima even, killed nobody, (but of course people totally forgot the enormous 1000s of casualties of the Tsunami!)

Penguins are not dying in Alaska because of background radiation.
Everyone will experience a lifetime dose which will inevitably kill some cells - which usually replicate perfectly normally.
It really gets up my nose this paranoia about perfectly normal energy and ionisation, states and somehow having to "WARN, DO SOMETHING, MAKE UP SOME STORY".
 
I just don't get this lethal codwallop. Lightning is only lethal, (and there not every time) if it strikes you.

My point was not that the electrons will leap across the room—the voltage is not high enough for that—but that accidental contact with a live circuit, or a charged capacitor, at these voltages can injure or kill.

We, those who build and repair amplifiers, are far more readily expose to such voltages than riders on the subway or underground. You are introducing a red herring.

High voltages are only lethal if you happen to slam a large current from one side of your body to the other through the heart area, and even then NOT ALWAYS....usually by sticking your stupid finger somewhere you shouldn't!

Accidents happen, particularly to people who work on such equipment, touch equipment where insulation breach or failure can occur, replace tubes, etc. If a tube cap, which most of those transmitter tubes have, is live, one can easily contact fatal levels of voltage.

Forty years ago I was working on a tube amplifier and grounded a hot chassis across my chest. I had touched my hand to the chassis while using a scope probe and with the other hand changed a setting on a oscilloscope and touched the metal chassis with the other hand. This was US mains voltage, so it was only 120 VAC. It was not lethal, but I learned to never trust a tube chassis. I was not being stupid, per se, but it was an accidental contact. I learned a valuable lesson. Most people who work on tube gear have similar stories.

My British co-workers told me similar stories for 240 VAC and how much worse that was. Others have told me stories about having high voltage DC where they couldn't let go.

I've also heard stories from guitarists about live chassis because of reversed plugs or failed death caps, and read such stories which include death as the outcome.

You routinely get on metros, electric trains where power lines above or below have voltages anything between 630V DC and 23Kv AC, yet I don't see everyone swooning or dying.

This is irrelevant and a red herring. I routinely drive by substations where AC transmission lines at hundreds of kV are stepped down. So what? This is not a tube amplifier on a bench or shelf.

Again, one is not on top of this as one would be with a tube amplifier and as long as one is on the platform, not inches away, the risk is non-existent.

Somehow the mere fact a potential difference exists of up to 1KV DC seems to make the tube audio brigade pronounce "shock horror" and a cult of the extraordinarily dangerous. This is just getting STUPID.

High voltage is dangerous. Denying this doesn't change the facts.

Fukujima even, killed nobody, (but of course people totally forgot the enormous 1000s of casualties of the Tsunami!)

Fukushima Daiichi was the worst nuclear disaster since Chernobyl, and vast quantities of radiation were released: 10% of the amount from Chernobyl. The ground is so contaminated that nobody will be able to live there for longer than human recorded history. The amount of contaminated seawater is unknown, but simply staggering.

Radioactive iodine and cesium were found in California waters.

The tsunami is irrelevant to whether or not it is safe for people to own or use equipment with high-voltage transmitting tubes operating at tens of kV.

All of this is a non-sequitur and a distraction; I merely point it out to rebut your argument.

It really gets up my nose this paranoia about perfectly normal energy and ionisation, states and somehow having to "WARN, DO SOMETHING, MAKE UP SOME STORY".

I did not fabricate any claims, and my off-hand observation remains cogent and true that 10 kVDC to 20 kVDC is a lethal voltage.

No need to be angry or hijack the thread to spout red herrings about radioactive penguins riding the subways to their jobs at nuclear-power plants. Such busy penguins, one wonders how they have time to eat, breed, or tangle with high voltage.

"Ever been to Utah? Ra-di-a-tion. Yes, indeed. You hear the most outrageous lies about it. Half-baked goggle-box do-gooders telling everybody it's bad for you. Pernicious nonsense. Everybody could stand a hundred chest X-rays a year. They ought to have them, too."—J. Frank Parnell*

* The quote, for those of you not familiar with 80's cult films, is from Repo Man (1984), a work of genius. The term "goggle-box" is slang for television, dating to the 1955 to 1960 period. Interesting how a minor change makes it into "google box" or computer.
 
We, those who build and repair amplifiers, are far more readily expose to such voltages
That's their fault. So what?
This was US mains voltage, so it was only 120 VAC.
Big deal! You weren't doing this in the bath were you?

My British co-workers told me similar stories for 240 VAC and how much worse that was.
No it's not, we were brought up with this in England, and our BS (not b..lls..hit - BUT BRITISH STANDARD) plugs are the safest in the world.
Nobody else makes shuttered plugs anywhere except the UK.
Kids can't kill themselves just by shoving pens and knitting needles in 'em.

Others have told me stories about having high voltage DC where they couldn't let go.
Well they obviously COULD because they wouldn't have been telling you about it...OR was it an Irish joke?

Fukushima Daiichi was the worst nuclear disaster since Chernobyl,

The ground is so contaminated that nobody will be able to live there for longer than human recorded history.

Sorry you are talking utter bollox.
It's perfectly safe to live close by, and they don't even eat mushrooms from the forests like they are doing now in Bielorussia.

let's get this straight, while we are on the subject.
What was the greatest radiation disaster ever?

It was the USA doing BAKER first in a lagoon, then making their b..l dy great big hydrogen bomb test CASTLE BRAVO which went totally beserk with the wind blowing the wrong way.

(Dr Strangelove was a real nutcase)!
300px-Castle_Bravo_Blast.jpg


Had it happened over the USA instead of some innocent islanders the entire country would have suffered enough fall out to poison half of the states for good.
So NIMBY (not in my back yard) never applies to the USA does it?
Then they can preach to others?

I don't need lectures from a country who are the only ones ever actually to nuke 2 cities, and behave like eco vandals for 30 years.

Of course we don't even need to think about what the USA did to the paradise lost of bikini do we,- never mind all those of your own servicemen you deliberately poisoned, yet when it comes to pointing the finger it's the US of A at it again!

You do realise the Bikini islanders can't live there ever again, and it is ENTIRELY the fault of the lying, cheating USA? It really reads like one of those tests from Stanley Millgram!
"It is neccessary for our experiment for you to follow orders no matter what!"

FYI little info:-
My father was one of the best friends of the chief radiation protection officer on Great Britain for many decades, as he worked next door to HARWELL. (The same Harwell, the HQ of the medical research council MRC)
(Mr I Jones was a Welsh speaking Welshman, - quite quiet and terse in English)
His job was cleaning up the mess when something stupid happened.

He could tell some interesting stories, ESPECIALLY how uninformed people reading the news and media have absolutely NO IDEA what they are on about.
(Big pinch of salt needed especially for Greenpeace biased cr..p)

Interestingly enough my Dad also worked for Mullard in Mitcham for a number of years, so I might know a little on both subjects.
 
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AB, you may have swallowed a little bit too much koolaid to present a fully rational point of view describing and framing relative cancer risks to the public. To date, there is no direct link between causative radiation exposure and cancer, just as there is no proof that increased cancer rates follow more/less radiation exposure. However, there is epidemiological data, and a fairly strong degree of correlation, that supports increased cancer incidence from increased exposure. Almost a third of us are going to have cancer in our lives, so there are many cancers that are caused merely by heredity and/or radiation exposure at background levels. Radiation risks are a nebulous field to argue, unless you get cancer, and then risk becomes a very personal thing.

"It's perfectly safe to live close by, and they don't even eat mushrooms from the forests like they are doing now in Bielorussia."
I would not go here until there is a strong body of investigative work accomplished by peer reviewed data reports from health physicists working on the issue as we speak. Good science means allowing the scientists to do their job, establishing relative risk models, and allowing the public to be educated so they can make informed decisions.

What was the greatest radiation disaster ever? It was the USA doing BAKER first in a lagoon, then making their b..l dy great big hydrogen bomb test CASTLE BRAVO which went totally beserk with the wind blowing the wrong way.
I would disagree here, both by amounts of fissile materials released, number of people impacted, and causative deaths. My list of disasters would be
1. Mayak/Kyshtym/Techa/Karachay plant complex, in the Russian Urals
2. Chernobyl
2a. Fukushima
3. Baker/Bravo
4. Three Mile Island

There are acres of land and exposed riverbed and lake bed downstream of the Mayak complex that are high and very high radiation areas, where people can walk into unfenced offsite areas that would kill them from radiation exposure within an hour. None of the other sites present such a hazard to the level that the Mayak area does. The river basin surrounding this complex provides drinking water for close to 30,000 people, and has from the first accidents and releases in 1947.

And, getting back to the original question, are vacuum tubes radioactive? The tubes the OP listed are all background, with the noise level of 5 microrem/hour here in St. Louis. We have a nice all brick ranch house built in 1957 from good St. Louis brick, which has higher trace levels of uranium, thorium, and radium, so our master bedroom is about 9 microrem/hour, and our study is 11 microrem/hour.

It takes a thousand microrem to equal(reach) one millirem, and we average about 1.5 to 2 millirem of background radiation exposure a day.

Five millirem/hour whole body exposure is the threshold for an occupational radiation area.
One thousand millirem equals one rem.
Five rem, or 5,000 millirem, is the legal annual exposure limit for occupational radiation workers.

The highest level I have ever measured on a radioactive vacuum tube, on contact with the envelope, is 90 microrem/hour, or 0.009 millirem/hour, or 0.000009 rem/hour. The risk is very, very small of contracting cancer by using the tube in your system. To give you a perspective, most medical research studies target smoking a pack of cigarettes a day with delivering between 1,000 to 1,500 millirem a year of radiation exposure to your lungs, a very large and pronounced level of exposure and cancer risk.
 
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radiation internally is also very different than whats outside the body. Much more dangerous.
 
I don't need lectures from a country who are the only ones ever actually to nuke 2 cities, and behave like eco vandals for 30 years.

(1) I wasn't aware I represented the entire country and was responsible for actions I did not commit.
(2) You never address the issue of high voltage, you just want to rant and rave.

Your anger is toxic and you are hijacking this thread which was whether or not tubes are radioactive.
 
Shuttered plugs?? No problem. I used them on my rear deck and only occasionally spray a few drops of lube in them to get them to work smoothly.
 
The only tubes I can think of that are radioactive-radioactive are TR tubes used in radars... but there are/were a lot of different applications over the years.
Tuned a few of those in my life.
Watched once a guy was working on the hatch switch or something above the TR tube and his ass came too close.
It arched and shut down as he jumped up, hit his head and collapsed and tumbled to the ground bout 15 feet. Knocked himself out.
We all bought him a beer that night as one after another we re enacted the event so he could see why we were laughing or butts off.
 
I don't need lectures from a country who are the only ones ever actually to nuke 2 cities, and behave like eco vandals for 30 years.

No but you are perfectly free to do so because of it. You and all your relations, friends acquaintances. Your hatred is not appreciated.
 
Tubes used in aviation are generally radioactive, but at very low levels. Atmospheric radiation (due to radiation from space and higher altitudes) is quite variable and wreaks havoc on the output of equipment with tubes, so they are doped with isotopes like cobalt 60, so that tends to swamp out the variability that comes from atmospheric, making the radiation effects on tube activity more stable.

Such tubes in military equipment are isolated out and dealt with appropriately in the bone yards for the birds, so it is not likely that they escape into the wild. The biggest bone yard for the AF is here in Tucson.

Tubes for commercial audio and radio gear I know nothing about.

As for radiation effects:
  • Alpha particles (essentially a helium nucleus) are the most ionizing, they penetrate the least, and are stopped by a sheet of paper or your skin. On the outside of your body they do little damage. But, if a material that releases they is inhaled or swallowed, quite a bit of cumulative damage will be sustained. Damage is generally due to contact ionization with the particles.
  • Beta particles are essentially free electrons. The ionize a bit less, but penetrate a bit more, causing burns. If materials release beta are swallowed or ingested, damage also accumulates, but a bit faster. Damage is generally due to collision by particles, and decreases with the square of the distance from the source.
  • Gamma is a high energy radiation that is the least ionizing but penetrates the most, requiring the most effective shielding to stop. Production intensity is the key to damage here. Since most passes through without causing damage, increases in intensity increase the likelihood of of interaction with molecules in the body, increasing the amount of damage produced. Damage is caused by energy transference and associated state changes and effects.
Alpha is stopped by paper. Glass will generally contain Beta. Gamma requires dense, thick shielding. This stuff is quite elementary but should be of some interest to the discussion.

Enjoy,
Rich P
 
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