[Eeglablist] question about shieldroom specifications

Makoto Miyakoshi mmiyakoshi at ucsd.edu
Thu Oct 16 16:09:40 PDT 2014

Dear Archana,

EEG signal range is 1-500Hz. Not even kiloHertz. Because of this, any
shield room is fine (i.e. does not work anyway).

The most problematic environmental artifact is 50/60Hz line noise. This is
hard to shield because of low frequency. I heard that you need a type of
magnetic shield instead of ordinary copper ones to shut it off.

I've seen labs that is not shielded. Their data tend to have higher 50/60Hz
line noise, but we can low-pass the data below that. Our Mobilab does not
have a shield either.

> I would like to know what does the cutoff in Hz represent.

The noise level is guaranteed to be attenuated to the specified levels.


On Wed, Oct 15, 2014 at 10:20 PM, Archana Singh <sine.arc at gmail.com> wrote:

> Dear All,
> I  hope that some of you have experience with construction of electric
> shielding room for your EEG experiments. I am negotiating with shieldroom
> companies for our new EEG lab.
> I would like to know how to interpret the shielding cutoff specifications.
> I have received various shielding specifications as follows. I know 40dB
> would be sufficient for our purpose, but I would like to know what does the
> cutoff in Hz represent.
> 100K-30MHz / 40dB
> 10-30MHz  / 80dB
> 500k-500MHz / 40dB
> Best,
> Archana
> __________________________________________
> Archana Singh,
> ERATO Researcher,
> Functional and Chemosensory brain imaging group
> Department of Applied Biological Chemistry
> Graduate School of Agricultural and Life Sciences
> The University of Tokyo, Tokyo 113-8657
> _______________________________________________
> Eeglablist page: http://sccn.ucsd.edu/eeglab/eeglabmail.html
> To unsubscribe, send an empty email to
> eeglablist-unsubscribe at sccn.ucsd.edu
> For digest mode, send an email with the subject "set digest mime" to
> eeglablist-request at sccn.ucsd.edu

Makoto Miyakoshi
Swartz Center for Computational Neuroscience
Institute for Neural Computation, University of California San Diego
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://sccn.ucsd.edu/pipermail/eeglablist/attachments/20141016/827db2ba/attachment.html>

More information about the eeglablist mailing list