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Environmental and Workplace Health

Understanding Safety Code 6

The Government of Canada is committed to protecting the health and safety of Canadians from environmental risks, including those posed by exposure to radiofrequency (RF) electromagnetic fields - the kind of energy given off by various electronic devices such as cell phones and Wi-Fi, as well as broadcasting antennae and cell phone towers.

The purpose of Safety Code 6 is to establish safety limits for human exposure to RF fields in the frequency range from 3 kHz to 300 GHz. The safety limits in this code apply to all individuals working at, or visiting, federally regulated sites. The limits established in Safety Code 6 incorporate large safety margins to provide a significant level of protection for all Canadians, including those working near RF sources.

The Code is divided into two sections. The first section is an introduction that provides an overview of the purpose and rationale of the Code, specifically outlining what electromagnetic radiation is and where RF fields fall within the electromagnetic radiation spectrum. The introduction also provides a high level synopsis of what the literature indicates with respect to the health impacts from human exposure to RF fields and how these health effects have been used in the establishment of the exposure limits within Safety Code 6.

The second and most significant section of the Code provides details on what the exposure limits are. The exposure limits are specified as "basic restrictions" (exposure limits within the body) and "reference levels" (exposure limits outside the body). The Code concludes with definitions of key terms used throughout the Code and a list of the key literature or reference materials used in the revisions to the Code.

While Health Canada recommends limits for safe human exposure, Health Canada does not regulate the general public's exposure to electromagnetic RF fields. However, many provinces and territories apply the exposure limits in Safety Code 6 for general public exposure. Wireless devices and their associated infrastructure (such as cell towers) are regulated by Industry Canada, and are required to comply with Safety Code 6.

Health Canada scientists monitor the scientific literature on this issue on an ongoing basis. Safety Code 6 is reviewed on a regular basis to verify that the guideline provides protection against all known potentially harmful health effects.

When developing the exposure limits in Safety Code 6, Health Canada considers all peer-reviewed scientific studies. The exposure limits in Safety Code 6 are set well below the lowest exposure level (threshold) at which any scientifically-established, adverse health effect occurs and take into account the total exposure from all sources of RF energy.

Canada's limits are consistent with the science-based standards used in other parts of the world (e.g., the United States, the European Union, Japan, Australia and New Zealand) and provide protection against all known adverse health effects from RF energy.

Reviewing Scientific Evidence on Safety Code 6

Safety Code 6 is reviewed on a regular basis to verify that the guideline provides protection against all known potentially harmful health effects. Health Canada employs a weight-of-evidence approach when reviewing scientific evidence that may have an impact on Safety Code 6. The weight-of-evidence approach takes into account both the quantity of studies and, more importantly, the quality of those studies.

Poorly conducted studies (e.g. inadequate exposure evaluation, lack of appropriate control samples or inadequate statistical analysis), receive relatively little weight, while properly conducted studies (e.g. all controls included, appropriate statistics, complete exposure evaluation) receive more weight.

International Standards

The limits in Safety Code 6 are science-based exposure limits that are consistent with the science-based standards used in other parts of the world, including the United States, the European Union, Japan, Australia and New Zealand.

Large safety margins have been incorporated into these limits to provide a significant level of protection for the general public and personnel working near RF sources.

Internationally, a few jurisdictions (cities, provinces or countries) have applied more restrictive limits for RF field exposures from cell towers, although there is no scientific basis to support the need for such restrictive limits. Additionally, in many instances these more restrictive limits are not applied to other wireless devices in these same jurisdictions.

Safety Code 6 protects all Canadians

The Safety Code 6 limits for human exposure to RF fields are designed to provide protection for all age groups, including children, on a continuous (24 hours a day/seven days a week) basis.

This means that if someone, including a small child, were to be exposed to RF fields from multiple sources for 24 hours a day, 365 days a year, within the Safety Code 6 limits, there would be no adverse health effects. Safety Code 6 exposure limits are not device specific, but the limits do take into account the total exposure from all sources of RF fields. Health Canada scientists have concluded (and the Royal Society of Canada has agreed) on the basis of current scientific data, that no adverse health effects will occur from exposure to RF fields at the levels permitted by Safety Code 6.

Health Canada reminds all Canadians that their health is protected from RF fields by the human exposure limits recommended in Safety Code 6. The current Safety Code establishes and maintains a human exposure limit that is far below the threshold for potentially adverse health effects.á The limits in Safety Code 6 provide protection against all known adverse health effects for all individuals.