In the spring of 2010, Toronto Water began the installation phase of their residential water meter program. Participation in the program is mandatory under Municipal Code 851 – Water Supply.

Toronto Water meters:

  • record water use in homes
  • are equipped with wireless transmitters installed in or outside the home
  • send meter readings to data collector/radio receiver units located across the city

Some residents have requested information on the potential health impact from exposure to the radiofrequencies (RFs) used to send meter readings to Toronto water.

Based on the review of available information, with details found below, Toronto Public Health concludes that the RF levels from water meters meet the City of Toronto (the City)’s policy of prudent avoidance.

It is unlikely that RFs from the water meters pose a health hazard to those who live in the homes or neighbourhoods where they are installed.


Industry Canada, a branch of the federal government, is responsible for the approval of RF-emitting devices as well as the implementation and enforcement of Safety Code 6, Health Canada’s guideline for exposure to RFs. Safety Code 6 establishes safety limits for human exposure to RF energy.

In 2012, Toronto Public Health (TPH) was asked by Toronto Water to review the information on RF levels from the new water meters and respond to public inquiries related to health. TPH looked at RF levels from various sources and compared them to City’s prudent avoidance policy. This policy applies to new cell phone towers and requests that RF levels limited to 1% of Safety Code 6 values for the general public.

Toronto Public Health has reviewed available literature and product information from the water meter manufacturer.

  • Toronto Water meters are different from smart meters.
  • They do not receive data.
  • They do not create a communication network with other residential meters.
  • The water meters collect the data then transmit it directly to a radio receiver unit at various non-residential locations throughout the city.
  • RFs only emit from the units during data transmission.
  • Data transmission occurs four times a day.
  • Each transmission period lasts 0.25 seconds for a total transmission time of one second per day.


Based on the information provided in the manufacturer’s document, the meters transmit RFs at 0.0143% of Health Canada’s Safety Code 6 guidelines, a value which is well below the 1% noted in the prudent avoidance policy.


The table below puts the RFs from water meters into context when considering individual exposure to RFs in the home or in the community.

Source Frequency Exposure Level
Distance Time Spatial Features
Cell Phone 900 MHz, 1800 MHz 1 – 5 At ear During call Highly localized
Microwave Owen 2450 MHz ~50
0.05 – 0.2
60 cm During use Localized, non-uniform
Local area networks (WiFi) 2.4 – 5 GHz 0.0002 – 0.001 (wireless router) 1 m Constant when nearby Localized, non-uniform
Smart Meters 900 MHz, 2400 MHz 0.002 – 0.0002 1 m – 3 m When in proximity during transmission Localized, non-uniform
Water Meters (TO) 450 – 470 MHz 0.000043 20 cm When in proximity during transmission Localized, non-uniform

Sources: Adapted from

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For more information, please contact Environmental Response Team (ERT), Healthy Environments: 416-392-7685