ERP Engineering

It’s that time of the year again – New Year’s resolutions are dying in droves, the Canadian winter still has its icy grip on much of the land, and if you’re a radio broadcaster in Canada that is due for licence renewal in 2018 you probably have received a letter that mentions the need for your station(s) to demonstrate compliance to Health Canada’s Safety Code 6.

Safety Code 6 contains the established limits of human exposure to radiofrequency electromagnetic energy in the frequency range of 3 kHz to 300 GHz, a frequency range that encompasses the FM and VHF/UHF television broadcast bands.  Here’s 3 things you should know about Safety Code 6:

Compliance to Safety Code 6 is an ongoing commitment, and a condition of license for all holders of a broadcast certificate.

In short, if you do not provide proof that your broadcast station complies with the Safety Code 6 standard, you will no longer be permitted to operate your broadcast transmitter.

There are multiple ways to determine the total radiofrequency energy levels at a broadcast site

Safety Code 6 contains radiofrequency (RF) energy limits for controlled environments and uncontrolled environments, the nuances of which will be explored in a future blog post.  The first method to determine the RF contributions of all transmitting services at the site is with detailed calculations.  Innovation, Science and Economic Development Canada (ISED) maintains public databases containing operating parameters for all licensed radiocommunication services in Canada (well, mostly anyway – for security purposes you won’t find details on wireless systems used by law enforcement groups, etc.).  These calculations must consider all broadcast transmitters located within 1 km and all non-broadcast (cellular, two-way radio, paging, microwave point-to-point, etc.) services located with 100 metres of the site in question.

The other option is to perform on-site measurements with specialized test equipment.  For complicated sites, such as building rooftops or tower sites crowded with antennas, measurements can be an ideal approach.

A broadcast site can exceed the RF limits in Safety Code 6 and still comply to the standard

Wait, what?  Recall that the purpose of Safety Code 6 is to ensure the safety of persons exposed to RF energy.  Through measures such as access control (fences, locked doors, etc.), tower anti-climb devices, and the posting of appropriate signage, a site can be compliant even if there are RF energy levels which exceed the prescribed limits in Safety Code 6.

Certainly there is more to the story than this, and more questions to be explored an answered.  Stay tuned for future blog posts written on this topic, or contact ERP Engineering today to continue the conversation.