FIRE FIGHTERS GUIDANCE NOTE # 3-4 ISSUE: RADIOFREQUENCY (RF) AWARENESS Consistent with the general duty clause 25(2)(h) of the Occupational Health and Safety Act (OHSA), employers are required to take every precaution reasonable in the circumstances to protect workers. Clause 25(2)(a) of the OHSA requires employers to provide information, instruction, and supervision to protect the health and safety of workers, and clause 25(2)(d) requires employers to acquaint a worker or a person in authority over a worker with any hazard in the work. Firefighters, in the course of their duties, may be exposed to non-ionizing radiation, such as radiofrequency (RF) radiation, as a result of Directional and Omni-Directional Antennae found on rooftops. Rooftops can present areas of high RF exposure because: the firefighter may be on the same horizontal plane as the antenna, where the signal is the strongest. rooftops may be heavily populated with different types of antennae, all transmitting at different power and frequencies. the signal strength of each antenna combines, creating a higher cumulative RF strength. a coaxial cable may be damaged and may leak a concentrated RF signal. Health hazards: The primary health concern is overheating and burns. Recommended exposure limits and more information on health hazards can be found in the Ministry of Labour Health and Safety Guideline Radiofrequency and Microwave Radiation in the Workplace, in Appendix G of this Manual. Effective: October 2015 Page 1
Equipment: Directional Antennae These antennae send and receive RF out in front of them. There is no RF energy behind them. Workers should avoid walking or working in front of these: Effective: October 2015 Page 2
Omni Directional Antennae These antennae transmit a 360 degree signal. Workers should avoid working or walking on the same plane as these: Microwave Dish Antennae often called a Drum Antennae (in the background) Folded Dipole Antennae (in the foreground) Effective: October 2015 Page 3
Considerations/recommendations for firefighters: Preplanning activities should identify antenna locations, their type and power sources, safe distances, lock out procedures, and site contacts. Always consider antennae as live unless locked out. Studies have shown that RF levels on the ground are thousands of times less than the Health Canada limits for safe exposure. In order to be exposed to levels at or above RF exposure limits, an individual would essentially have to remain in the main transmitting beam (at the height of the antenna) and within a few feet from the antenna. When setting up ladders or aerial devices consider the conditions of the site. Avoid operation of the ladder into or through the beam of RF transmission. Ungrounded conductors (i.e. ladders) in the beam may present a shock hazard. Rooftops in urban areas may be highly populated with RF transmitters. Antennae may also be mounted on elevator penthouses, at the edge or over the side of building walls, and may be disguised as or located within other objects (i.e. flagpoles, steeples, trees, signs, etc.). Do not look into the ends of open coaxial cable or remain close to visibly damaged cable. These cables carry concentrated RF signal. Sample Signs Identifying High RF Areas Effective: October 2015 Page 4
References: GN # 6-16 Machinery/Electrical Lockout During Emergency Response GN # 6-14 Safe Roof Operations GN # 6-8 Firefighter Safety During Lightning Storms Appendix G of this Manual - Ministry of Labour Health and Safety Guideline: Radiofrequency and Microwave Radiation in the Workplace For more information about radiation protection for workers, please call the Radiation Protection Service at (416) 235-5922. Effective: October 2015 Page 5