Re: Safety presentation to non-ra personnel

[P.Hill@kfa-juelich.de (Peter Hill )]

>They are using several varieties of thoriated weld rods and I
>would like to find out more about these rods. 
>

During the last meeting of the working group on incorporation monitoring of
the German Fachverband fuer Strahlenschutz e.V. (the equivalent to HPS) ,
which  we organized here in Juelich there was a talk presented by T.Ludwig
and G.Seitz on Thorium Exposure during Welding and Grinding with thoriated
tungsten Electrodes.

Thorium might be emitted during welding (especially altenate current
welding), as well as during grinding of the electrodes. Using thoriated
electrodes at welding without technical ventilation could lead to annual
body burdens of about 200 Bq Th-232, which is far beyond the limits set by
German regulations for non radiation workers. Also only about 400 grindings
per year would already lead to body burdens beyond this limit. Ludwig and
Seitz conclude that :
- where possible thorium free electrodes should be used
- welding with thoriated electrodes should only be done with technical
ventilation/exhausting
- for grinding the electrodes the use of an exhauster on the wheelstand is
always recommended.When cleaning the waste box of the wheel stand breath
protective equipment should  be used. 
- it is suggested that the Welders grind their electrodes themselves instead
of one person grinding all the electrodes of a number of welders, as is
common practice in some factories.

Conclusions and recommendations of Ludwig and Seitz are based on
experimental investigations in 26 factories. They are affiliated with the
Berufsgenossenschaft fuer Feinmechanik und Elektrotechnik,
Koeln(Cologne),Germany.(industrial insurance company).

Some work has been done on this subject by our institute in collaboration
with the university of Wuppertal, too. However up to now the funding agency
reserves the right of publication of the results for itself. Sorry about that.

Kind regards


 
 

 Dr.Peter Hill                          phone: +49-2461-61-5081
 Forschungszentrum Juelich GmbH         fax  : +49-2461-61-3726
 D-52425 Juelich/Germany            email:P.Hill@kfa-juelich.de
 
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