Re: Magnetic Field Surveys

[c-m-meyer@tamu.edu (Christopher M. Meyer)]

Bernard L Cohen wrote:

>	There may be a confusion here between AC and DC magnetic fields. 
>I get the impression that your magnetic fields are DC, whereas the ones 
>that people worry about are AC. If you are worried about AC fields, a 
>meter to measure them costs only about $100, so it is cheaper to buy one 
>than to hire a consultant.
>

You are correct that these are DC fields.  You are also correct that DC
fields (at or around 5 gauss) are safe, even for persons wearing pacemakers.
However, the problem is that "the public" does not make the distinction
between AC and DC magnetic fields. 

We are still in the midst of just such a problem.  The DC fields, while
within the acceptable range in some adjacent offices, did affect computer
monitors.  By extension, the people in those offices assumed that if the
fields can affect their monitors, there is no telling what damage it is
doing to their long-term health.  Radiation Safety was unable to allay their
fears.  University administration elected to require the researcher to
install extensive shielding. The expense and efficacy of the shielding and
the effects on the researcher's magnetic fields have yet to be determined.

Chris Meyer
Radiation Safety Officer
Texas A&M University
c-m-meyer@tamu.edu

Standard disclaimer applies...