ELF Effects on VDUs

[a.zapantis@qut.edu.au (Alex Zapantis)]

G'day Radsafers

I recently completed an ELF (50Hz) survey in an office which backs onto an
11000V transformer. As expected, the magnetic flux densities were quite high
- eg a maximum of 640mG at the closest point to the transformer. The
magnetic flux density at the point where the VDU is situated is about 30mG.
This appears to be causing a "wavering" effect in the screen.

My question is does anyone have a feeling for the minimum magnetic flux
density (50Hz) required to cause such an effect in a VDU screen?

Thanks in advance

regards



                        Alex Zapantis
                        Radiation Safety Officer                               
                        Queensland University of Technology          
                        Health & Safety Section                             
                        Locked Bag No.2
                        Red Hill Qld 4059
                        AUSTRALIA

                        Ph     : 61 7 864 3566
                        fax     : 61 7 864 3993
                        email  : a.zapantis@qut.edu.au