IEEE Committee on Man And Radiation—COMAR Technical Information Statement Radiofrequency Safety and Utility Smart Meters

Abstract

This Technical Information Statement describes Smart Meter technology as used with modern electric power metering systems and focuses on the radio frequency (RF) emissions associated with their operation relative to human RF exposure limits. Smart Meters typically employ low power (−1 W or less) transmitters that wirelessly send electric energy usage data to the utility company several times per day in the form of brief, pulsed emissions in the unlicensed frequency bands of 902−928 MHz and 2.4−2.48 GHz or on other nearby frequencies. Most Smart Meters operate as wireless mesh networks where each Smart Meter can communicate with other neighboring meters to relay data to a data collection point in the region. This communication process includes RF emissions from Smart Meters representing energy usage as well as the relaying of data from other meters and emissions associated with maintaining the meter’s hierarchy within the wireless network. As a consequence, most Smart Meters emit RF pulses throughout the day, more at certain times and less at others. However, the duty cycle associated with all of these emissions is very small, typically less than 1%, and most of the time far less than 1%, meaning that most Smart Meters actually transmit RF fields for only a few minutes per day at most. The low peak power of Smart Meters and the very low duty cycles lead to the fact that accessible RF fields near Smart Meters are far below both U.S. and international RF safety limits whether judged on the basis of instantaneous peak power densities or time-averaged exposures. This conclusion holds for Smart Meters alone or installed in large banks of meters.