[Amps] BeO in tubes

[Nils Petter Pedersen]

Hi !
Found this link. Relevant info on hazards of Beryllium oxide.
Seems to be more to it than long term effects ( ?? )
Interested parties should have a look.
http://www.inchem.org/documents/icsc/icsc/eics1325.htm
73's Peter
LA7SL

----- Original Message ----- 
From: "John Lyles" <jtml at losalamos.com>
To: <amps at contesting.com>
Sent: Sunday, November 18, 2007 6:54 PM
Subject: [Amps] BeO in tubes


> Exactly, BeO is similar to asbestos in that it causes lung tissue damage 
> (berylliosis - pardon for spelling) that can eventually develop into 
> cancer. Although not in all cases. I know a guy (a ham) who machined it 
> for years, and is always short of breath. Its a terrible thing. I believe 
> that Eimac included that little red and white note in EVERY tube box, as 
> it was probably simpler to do that than to try and get the proper 
> notification into the proper tube carton in the shipping department. If 
> they had not warned of the hazard, they could have been proven negligent 
> in a lawsuit. Reading those notes, they always said something like "this 
> tube MAY have BeO ceramic".
>
> There are pegmatite veins (called dikes) in the mountains near my QTH and 
> one mine I have visited used to have meter long beryl crystals. In mid 
> 1940s the miners extracted microlite, an ore of tantalum and niobium, from 
> there. It was used for wartime work for electronic parts and tube elements 
> (plates, getters). In the 1950s they extracted beryllium cyclosilicate 
> ore. It was the leading beryl producer in North America in 1950-51, 
> exceeding 13,000 kg per year. In 1958 the miner working the claim died, 
> and production  ceased - over 690 tons of 11.2% BeO and 184 tons of 5.5% 
> had been shipped from that one mine. Four miners dug and hauled the ore 
> out. During the best days, they would bring about about a ton per day by 
> hand. A mule named Beryl lived there and stayed in the mine for years. 
> Needless to say, there were no dust masks or OSHA/MSHA safety regulations 
> then. So most of them had that disease.
>
> A side note, Be was also used in neutron sources and neutron reflectors, 
> and some of the early metal came from that same mine, for the Manhattin 
> project, according to something I read.
>
>
> Sorry to digress from amplifiers!
> 73
> John
> K5PRO, northern New Mexico
>
>
>
>
>
> Message: 2
>> Date: Sun, 18 Nov 2007 08:51:39 +0000
>> From: Steve Thompson <g8gsq at eltac.co.uk>
>> Subject: Re: [Amps] Misconceptions about hazmat in ham radio equip
>> To: amps at contesting.com
>> Message-ID: <473FFD1B.80502 at eltac.co.uk>
>> Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>>
>> John Lyles wrote:
>>
>> > Now for beryllia. It is used in SOME power tubes, not LOTS of them. 
>> > Eimac had to include a disclaimer about it with every tube....
>>
>> I'm intrigued by 'had to' - do you know why?
>>
>> It is also in beryllium-copper metal used for EMI gasket material
>>
>> As I understand it: Be metal in BeCu is very safe. Raw Be is
>> nasty, but no-one will encounter it in normal life. BeO is toxic
>> in the same was as asbestos - it's not poisonous, but the
>> particles cause chronic lung irritation that can develop into cancer.
>>
>> Steve
>>
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