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4. Controlling RF/MW Radiation

Disclaimer: This resource has been prepared to help the workplace parties understand some of their obligations under the Occupational Health and Safety Act (OHSA) and regulations. It is not legal advice. It is not intended to replace the OHSA or the regulations. For further information please see full disclaimer.

Engineering Controls

  • RF/MW sources are regulated under the federal Radiation Emitting Devices Act. This Act is administered by Health Canada and enforced by Innovation, Science and Economic Development Canada.
  • Sources of RF/MW radiation should be properly shielded to minimize stray radiation.
  • Devices which can produce acute thermal injuries (e.g., industrial MW ovens) should have interlocked doors.
  • Devices which produce high levels of stray RF radiation (e.g., induction heaters, vinyl welders and dielectric heaters) should be operated remotely whenever possible.

Administrative controls

  • Training appropriate to the potential level of RF/MW exposure should be provided to workers.
  • Controlled spaces should be clearly demarcated.
  • Exposure of workers to RF/MW radiation should not exceed the recommended occupational exposure limits.
  • Areas where it is suspected that worker exposure to RF/MW radiation could exceed the recommended limits should be surveyed to determine the exposure levels.
  • Needless exposure to RF/MW fields should be avoided.
  • Exposure times should be kept as short as reasonably possible.
  • Potentially hazardous RF/MW devices should be appropriately labeled, and areas of excessive exposure around them clearly demarcated. Notices with warnings and the necessary precautions should be posted.
  • Electrically-activated explosive devices should not be placed near sources of RF/MW radiation.
  • RF/MW devices should not be used in flammable or explosive atmospheres.
  • Equipment sensitive to RF/MW radiation, such as telephone switchboards or control panels, should not be installed near sources of RF/MW radiation.
  • Maintenance of devices used to produce RF/MW radiation should be done by qualified personnel following standard safety procedures. The equipment should be turned off whenever possible.

Personal protection

  • When exposures cannot be reduced by the above methods, RF/MW protective suits, including head and eye protection, can be used. Suits should be tested to determine whether they reduce worker exposure to levels below the recommended occupational exposure limits for controlled spaces, and that they do not pose any additional safety hazards to workers (e.g., from overheating, shocks or fire).

Controlling RF shocks and burns

  • Metallic structures producing contact shocks should be electrically grounded and/or insulated.
  • Insulating platforms or shoes (e.g., rubber-soled shoes) can be used to reduce energy absorption and currents to the ground.
  • When the above measures are ineffective or not reasonably possible, workers should wear insulating gloves.

First aid

  • Remove worker from exposure area to a cool environment and provide cool drinking water.
  • Apply cold water or ice to burned areas.
  • Seek immediate medical attention.
  • Severe MW or RF overexposure may damage internal tissues without apparent skin injury, so a follow-up physical examination is advisable.

For more information

For more information about radiation protection in the workplace, please call the Radiation Protection Service at (416) 235-5922.


Health Canada

The Royal Society of Canada


ISBN: 978-1-4606-7601-1 (HTML)

Disclaimer: This web resource has been prepared to assist the workplace parties in understanding some of their obligations under the Occupational Health and Safety Act (OHSA) and the regulations. It is not intended to replace the OHSA or the regulations and reference should always be made to the official version of the legislation.

It is the responsibility of the workplace parties to ensure compliance with the legislation. This web resource does not constitute legal advice. If you require assistance with respect to the interpretation of the legislation and its potential application in specific circumstances, please contact your legal counsel.

While this web resource will also be available to Ministry of Labour inspectors, they will apply and enforce the OHSA and its regulations based on the facts as they may find them in the workplace. This web resource does not affect their enforcement discretion in any way.