I have been interested in the furore over the lost capsule, but it did make
me think about radioactive sources found in the home such as in smoke
alarms. Now I know these are quite small and supposedly well shielded but
what happens when these things are recycled? My local tip simply advised me
to sling some broken ones into the electrical waste, should they be
disposed of separately?

https://www.bbc.co.uk/news/world-64512297

Richard

Tricky Dicky wrote:

> I have been interested in the furore over the lost capsule, but it did make
> me think about radioactive sources found in the home such as in smoke
> alarms. Now I know these are quite small and supposedly well shielded but
> what happens when these things are recycled? My local tip simply advised me
> to sling some broken ones into the electrical waste, should they be
> disposed of separately?

<https://www.ezag.co.uk/radioactive-waste-solutions/radioactive-waste-disposal/smoke-detectors>

"As a private household you are permitted to dispose of your
radioactive smoke alarm to household waste, however many local
authorities would prefer that you remove the battery and take
your smoke detector to your local household waste recycling
centre."

On 04/02/2023 12:42, Tricky Dicky wrote:
>
> I have been interested in the furore over the lost capsule, but it did make
> me think about radioactive sources found in the home such as in smoke
> alarms. Now I know these are quite small and supposedly well shielded but
> what happens when these things are recycled? My local tip simply advised me
> to sling some broken ones into the electrical waste, should they be
> disposed of separately?
>
> https://www.bbc.co.uk/news/world-64512297
>
> Richard
>
They probably end up in landfill anyway.
IIRC the isotopes in smoke alarms are all alpha radiation and its not
very penetrating.

"Ionization smoke detectors use americium as a source of alpha
particles. Alpha particles from the americium source ionize air
molecules. This makes some particles positively charged and some
negatively charged. Two charged plates inside of the ionization smoke
detector create a flow of positively and negatively charged ions. The
smoke alarm triggers when smoke breaks the constant flow of ions.

Alpha particles are very heavy and cannot travel very far. They can be
shielded by a layer as thin as a layer of dead skin cells. Ionization
smoke detectors have a small americium source encased in a layer of foil
and ceramic, which stops the alpha particles from travelling outside of
the smoke detector. Because of this shielding, the smoke detector poses
no radiation health risk when they are properly handled.

There is no health threat from ionization smoke detectors as long as the
detector is not damaged and used as directed. Do not tamper with your
smoke detectors, as it could damage the shielding around the radioactive
source inside of them. There are no special disposal instructions for
ionization smoke detectors. They may be thrown away with household
garbage, or your community may have a separate recycling program."

blah blah blah.

--
"Anyone who believes that the laws of physics are mere social
conventions is invited to try transgressing those conventions from the
windows of my apartment. (I live on the twenty-first floor.) "

Alan Sokal

On 2/4/2023 7:42 AM, Tricky Dicky wrote:
>
> I have been interested in the furore over the lost capsule, but it did make
> me think about radioactive sources found in the home such as in smoke
> alarms. Now I know these are quite small and supposedly well shielded but
> what happens when these things are recycled? My local tip simply advised me
> to sling some broken ones into the electrical waste, should they be
> disposed of separately?
>
> https://www.bbc.co.uk/news/world-64512297
>
> Richard
>

The Australians found that little capsule by the way.

https://www.bbc.com/news/world-australia-64483271

Paul

I am not aware of the story, baton the second question, my smoke alarm says
it has no radioactive parts inside. The one before that claimed it would
wear out in 10 years as the source of the alpha radiation gradually
reduced. The very first one I had had a big box inside with a yellow label
and a skull and crossbones on it warning to not just throw it in the
rubbish.

So from this I was under the opinion that these days some other way of
detecting smoke was in use, perhaps optical rather than changes in the
ionisation current.

Brian

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"Tricky Dicky" <tricky.dicky@sky.com> wrote in message
news:trljrd$1vh9b$1@dont-email.me...
>
> I have been interested in the furore over the lost capsule, but it did
> make
> me think about radioactive sources found in the home such as in smoke
> alarms. Now I know these are quite small and supposedly well shielded but
> what happens when these things are recycled? My local tip simply advised
> me
> to sling some broken ones into the electrical waste, should they be
> disposed of separately?
>
> https://www.bbc.co.uk/news/world-64512297
>
> Richard
>

The ones I have now have no user replicable battery. When the battery dies
send Amazon a nice fiver or whatever and you shall have a new one.
Brian

--

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This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...
briang1@blueyonder.co.uk
Blind user, so no pictures please
Note this Signature is meaningless.!
"Andy Burns" <usenet@andyburns.uk> wrote in message
news:k475gaF18e4U1@mid.individual.net...
> Tricky Dicky wrote:
>
>> I have been interested in the furore over the lost capsule, but it did
>> make
>> me think about radioactive sources found in the home such as in smoke
>> alarms. Now I know these are quite small and supposedly well shielded but
>> what happens when these things are recycled? My local tip simply advised
>> me
>> to sling some broken ones into the electrical waste, should they be
>> disposed of separately?
>
> <https://www.ezag.co.uk/radioactive-waste-solutions/radioactive-waste-disposal/smoke-detectors>
>
> "As a private household you are permitted to dispose of your
> radioactive smoke alarm to household waste, however many local
> authorities would prefer that you remove the battery and take
> your smoke detector to your local household waste recycling
> centre."
>

What happened to all of those betalite things inside dial trimphones then?
These I gather had a radioactive gas inside and this made the coating on the
glass glow to allow the numbers to be seen.
Being beta and a gas, I'd have thought that these were more dangerous. I
also recall a product that you pulled up a central stem on them and placed
then near the edge of a record as you played it and it dissipated the
static. That has to have been radiation, or was it snake oil?

Oh and what about all those millions of tin alarm clocks made in Hong Kong
back in the 50s with those dobs of glowing green paint at the hour markers?

Brian

--

--:
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...
briang1@blueyonder.co.uk
Blind user, so no pictures please
Note this Signature is meaningless.!
"The Natural Philosopher" <tnp@invalid.invalid> wrote in message
news:trm1o1$21v0m$1@dont-email.me...
> On 04/02/2023 12:42, Tricky Dicky wrote:
>>
>> I have been interested in the furore over the lost capsule, but it did
>> make
>> me think about radioactive sources found in the home such as in smoke
>> alarms. Now I know these are quite small and supposedly well shielded but
>> what happens when these things are recycled? My local tip simply advised
>> me
>> to sling some broken ones into the electrical waste, should they be
>> disposed of separately?
>>
>> https://www.bbc.co.uk/news/world-64512297
>>
>> Richard
>>
> They probably end up in landfill anyway.
> IIRC the isotopes in smoke alarms are all alpha radiation and its not very
> penetrating.
>
> "Ionization smoke detectors use americium as a source of alpha particles.
> Alpha particles from the americium source ionize air molecules. This makes
> some particles positively charged and some negatively charged. Two charged
> plates inside of the ionization smoke detector create a flow of positively
> and negatively charged ions. The smoke alarm triggers when smoke breaks
> the constant flow of ions.
>
> Alpha particles are very heavy and cannot travel very far. They can be
> shielded by a layer as thin as a layer of dead skin cells. Ionization
> smoke detectors have a small americium source encased in a layer of foil
> and ceramic, which stops the alpha particles from travelling outside of
> the smoke detector. Because of this shielding, the smoke detector poses no
> radiation health risk when they are properly handled.
>
> There is no health threat from ionization smoke detectors as long as the
> detector is not damaged and used as directed. Do not tamper with your
> smoke detectors, as it could damage the shielding around the radioactive
> source inside of them. There are no special disposal instructions for
> ionization smoke detectors. They may be thrown away with household
> garbage, or your community may have a separate recycling program."
>
> blah blah blah.
>
>
>
> --
> "Anyone who believes that the laws of physics are mere social conventions
> is invited to try transgressing those conventions from the windows of my
> apartment. (I live on the twenty-first floor.) "
>
> Alan Sokal
>

On 05 Feb 2023 at 11:41:03 GMT, ""Brian Gaff"" <brian1gaff@gmail.com> wrote:

> What happened to all of those betalite things inside dial trimphones then?
> These I gather had a radioactive gas inside and this made the coating on the
> glass glow to allow the numbers to be seen.

Possibly tritium which is the radioactive isotope of Hydrogen. Half-life 12
years. Only a small amount will be needed. Decays by beta emission to become
Helium-3.

> Oh and what about all those millions of tin alarm clocks made in Hong Kong
> back in the 50s with those dobs of glowing green paint at the hour markers?

Poor sods doing those have prolly got cancer of the tongue or throat from
licking their brushes.

--
The truth of the matter is that we Scots have always been more divided amongst ourselves than pitted against the English. Scottish history before the Union of Parliaments is a gloomy, violent tale of murders, feuds, and tribal revenge. Only after the Act of Union did Highlanders and Lowlanders, Picts and Celts, begin to recognise one another as fellow citizens.

Tam Dalyell

On 05/02/2023 11:51, Tim Streater wrote:
> On 05 Feb 2023 at 11:41:03 GMT, ""Brian Gaff"" <brian1gaff@gmail.com> wrote:
>
>> What happened to all of those betalite things inside dial trimphones then?
>> These I gather had a radioactive gas inside and this made the coating on the
>> glass glow to allow the numbers to be seen.
>
> Possibly tritium which is the radioactive isotope of Hydrogen. Half-life 12
> years. Only a small amount will be needed. Decays by beta emission to become
> Helium-3.
>
>> Oh and what about all those millions of tin alarm clocks made in Hong Kong
>> back in the 50s with those dobs of glowing green paint at the hour markers?
>
> Poor sods doing those have prolly got cancer of the tongue or throat from
> licking their brushes.
>
They did in the 1940s. But they stopped them doing that. Cancers on the
tongue and lips IIRC

--
Truth welcomes investigation because truth knows investigation will lead
to converts. It is deception that uses all the other techniques.

On 05/02/2023 11:41, Brian Gaff wrote:

> What happened to all of those betalite things inside dial trimphones then?
> These I gather had a radioactive gas inside and this made the coating on the
> glass glow to allow the numbers to be seen.

> Being beta and a gas, I'd have thought that these were more dangerous. I
> also recall a product that you pulled up a central stem on them and placed
> then near the edge of a record as you played it and it dissipated the
> static. That has to have been radiation, or was it snake oil?

I don't know to what you refer, and don't see the connection between
static and radiation.

> Oh and what about all those millions of tin alarm clocks made in Hong Kong
> back in the 50s with those dobs of glowing green paint at the hour markers?

They could be phosphorescent paint that absorbs light in the daytime and
releases it at night. I think nearly all modern luminous watches use
that method. Trimphones used radioluminicesence, using tritium (the
radioactive isotope of hydrogen) as the energy source. Watch dials like
old Rolexes used a similar method. It's a long time since radium was
used for the purposes, with silly girls painting their fingernails with
radium.

--
Max Demian

On 05/02/2023 11:32, Brian Gaff wrote:

> I am not aware of the story, baton the second question, my smoke alarm says
> it has no radioactive parts inside. The one before that claimed it would
> wear out in 10 years as the source of the alpha radiation gradually
> reduced. The very first one I had had a big box inside with a yellow label
> and a skull and crossbones on it warning to not just throw it in the
> rubbish.

Americium-241 has a half life of 432.2 years so it can't be that. I
think the detector clogs up with dust, which is why, with modern
detectors, you have to replace the whole thing not the battery.

> So from this I was under the opinion that these days some other way of
> detecting smoke was in use, perhaps optical rather than changes in the
> ionisation current.

I don't think the optical type would be anything like as sensitive as it
would require visible smoke.

--
Max Demian