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Canada's Safety Code 6 - Online Training

The exposure limits in Safety Code 6 are based on an ongoing review of published scientific studies, including both internal and external authoritative reviews of the scientific literature, as well as Health Canada's own research.  The current version of these exposure guidelines is specified in a document entitled: Limits of Human Exposure to Radiofrequency Electromagnetic Energy in the Frequency Range from 3 kHz to 300 GHz - Safety Code 6 (2015). This code is accompanied by the Technical Guide for Interpretation and Compliance Assessment of Health Canada's Radiofrequency Exposure Guidelines, to assist users in understanding and assessing the safety of electromagnetic exposures in working and living environments.

The 2015 version of this code, is one of a series of safety codes prepared by the Consumer and Clinical Radiation Protection Bureau, Health Canada. These safety codes specify the requirements for the safe use of, or exposure to, radiation emitting devices. This revision replaces the previous version of Safety Code 6 (2009).  Please see download for complete documentation

1.1 Purpose of the Code

The purpose of this code is to specify maximum levels of human exposure to RF fields at frequencies between 3 kHz and 300 GHz, to prevent adverse human health effects in both controlled and uncontrolled environments.

Controlled Environments:

  • the RF field intensities in the controlled area have been adequately characterized by means of measurements or calculation,

  • the exposure is incurred by persons who are aware of the potential for RF exposure and are cognizant of the intensity of the RF fields in their environment and,

  • the exposure is incurred by persons who are aware of the potential health risks associated with RF field exposures and can control their risk using mitigation strategies.

Uncontrolled Environments:

areas where either insufficient assessment of RF fields has been conducted or where persons who are allowed access to these areas have not received proper RF field awareness/safety training and have no means to assess or, if required, to mitigate their exposure to RF fields and do not meet the specifications listed above.

2.1 Basic Restrictions

2.1.1 Internal Electric Field Strength Limits (3 kHz–10 MHz) Limits for internal electric field strength are intended to prevent the occurrence of NS. At frequencies between 3 kHz and 10 MHz, basic restrictions for internal electric field strength in excitable tissues (Table 1) shall not be exceeded. For conditions where the determination of internal electric field strength is not possible or practical (e.g. by measurement or modelling), external unperturbed field strength assessment shall be carried out and the reference levels outlined in Section 2.2 shall be respected.

2.1.2 Specific Absorption Rate Limits (100 kHz–6 GHz) The SAR is a measure of the rate at which electromagnetic energy is absorbed in the body. Basic restrictions for SAR are intended to prevent the occurrence of thermal effects from RF energy exposure on the body. At frequencies between 100 kHz and 6 GHz, the SAR limits (Table 2) take precedence over field strength and power density reference levels (Section 2.2) and shall not be exceeded. The SAR should be determined for situations where exposures occur at a distance of 0.2 m or less from the source. In all cases, the values in Table 2 shall not be exceeded. For conditions where SAR determination is impractical, external unperturbed field strength or power density measurements shall be carried out and the limits outlined in Section 2.2 shall be respected.

2.1.3 Frequencies from 6 GHz–300 GHz For frequencies above 6 GHz, energy deposition occurs predominantly in the uppermost layers of superficial tissues (e.g. skin, cornea). In this case, power density is a more appropriate exposure limit metric. Therefore, for the frequency range from 6 GHz to 300 GHz, the incident unperturbed power density and its derived electric- and magnetic-field strengths (assuming a free-space impedance of 377 ohms) form the basic restriction in this safety code (Section 2.2.2) and shall not be exceeded.

2.2 Reference Levels

2.2.1 Electric and Magnetic Field Strength (3 kHz–10 MHz) To ensure compliance with the basic restrictions outlined in Section 2.1, at frequencies between 0.003 MHz and 10 MHz, both the NS- and SAR-based reference levels for electric and magnetic-field strength must be complied with simultaneously at frequencies where reference levels for both apply.

2.2.2 Electric Field Strength, Magnetic Field Strength and Power Density (10 MHz–300 GHz) To ensure compliance with the basic restrictions outlined in Section 2.1, at frequencies between 10 MHz and 300 GHz, the reference levels for electric- and magnetic-field strength and power density must be complied with.

2.2.3 Induced and Contact Current (3 kHz–110 MHz) Induced current is defined as the current flowing through a single foot to ground in a free-standing body (no contact with conductive objects) exposed to an electric field. Where assessment is made of the current flowing through both feet, the result shall be compared to twice the reference level for a single foot.

 

Contact current is defined as the total current flowing through the body to ground resulting from finger-touch contact with a conductive object insulated from the ground that has been energized in an electric field. Conversely, it can be defined as the total current flowing in an insulated body that has been energized in an electric field and is in finger-touch contact with a grounded conductive object. The current path in the body is from point of touch to ground through the feet. The total current can be assessed anywhere along the path of flow.

The 2015 version of this code, is one of a series of safety codes prepared by the Consumer and Clinical Radiation Protection Bureau, Health Canada. These safety codes specify the requirements for the safe use of, or exposure to, radiation emitting devices. This revision replaces the previous version of Safety Code 6 (2009).  Please see download for complete documentation

2.2 Reference Levels

2.2.1 Electric and Magnetic Field Strength (3 kHz–10 MHz) To ensure compliance with the basic restrictions outlined in Section 2.1, at frequencies between 0.003 MHz and 10 MHz, both the NS- and SAR-based reference levels for electric and magnetic-field strength must be complied with simultaneously at frequencies where reference levels for both apply.