We have heard many reports of interference with people’s heart pacemakers, with implanted devices designed to improve symptoms for Parkinson’s patients, and with other medical devices.  Smart meters can interfere with medical devices in three ways.

First there is a 900 Mhz radio transmitter designed to transmit not only your own electric usage but also act as a relay for all your neighbors meters.

Next a 2.4 Ghz radio transmitter which is designed to communicate through a ‘Zigbee network” with the new ‘smart appliances’ you will soon be forced to buy. 

Lastly the new meters, even if the first two radios are ‘turned off’, contain something called a “switched mode power supply” which puts pulses on the wiring all through your house – what is known as “dirty electricity”.   Here is link to a story about the switched mode power supply.