High Power Trial - Compliance Level Re-assessment

As part of the evaluation of the High Power Trial over 2012-13, the ACMA has been auditing the applications of amateur licensees holding temporary high power licence variations.

As a result, the EMR Calculator, developed by Doug McArthur VK3UM and available via the WIA website, has been updated to provide improved guidance to all amateurs undertaking assessment of their stations’ compliance with electromagnetic radiation (EMR) requirements, whether or not they hold or wish to seek a high power licence variation.

The ACMA’s intention from the audit is to gauge Amateurs’ level of understanding of, and compliance with, the EMR exposure requirements as part of its decision in considering a permanent power increase for Advanced amateur licensees.

The requirements of EMR compliance are complex, and the audit found that a number of stations that believed they were operating under a Level 1 (low risk) Compliance should have, in fact, been classed as Level 2 (medium risk) Compliance.

Many of these licensees used the EMR Calculator on the WIA website, developed by Doug McArthur VK3UM. Upon investigation, it was found there was a discrepancy between the requirements of the Amateur Licence Conditions Determination (the LCD) and the output of the EMR Calculator, with respect to antenna accessibility. This discrepancy appears to have arisen from the exposure levels specified in the Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) Standard, on which the EMR Calculator’s results are based, and the exposure compliance requirements in the Amateur LCD.

The EMR Calculator provided an accurate calculation of exposure levels for various station scenarios and drew a conclusion about the ACMA compliance, based on the actual calculated exposure levels.

However, in the LCD, the exposure compliance level is determined by a set of simplified station conditions, rather than actual exposure levels, and this is the requirement that the ACMA determined should apply.

In particular, stations running over 100 watts average power (greater than 400 Watts PEP) were classed by the EMR Calculator as Compliance Level 1 when the minimum antenna height was less than 10 metres, but this was at odds with the LCD’s compliance requirements.

The ACMA will be writing to those licensees affected, advising them to re-evaluate their station.

An information page titled "Amateur Radio And EMR Issues" been placed on the WIA website providing guidance in clarifying the EMR compliance requirements. It is available via the following Link or via the "Technical Reference" section of the WIA Website accessible under the "For Members" drop down menu.

Doug VK3UM has now tweaked the EMR Calculator to fully comply with the ACMA requirements, and all licensees taking part in the High Power Trial should now re-evaluate their station using the VK3UM calculator which is available for download via the "Amateur Radio And EMR Issues" web page.

Doug VK3UM and Roger Harrison VK2ZRH consulted with the ACMA to address the issues identified during the ACMA’s audit, and worked together to update the EMR Calculator and extend its functionality. The WIA sincerely thanks everyone involved for the work done to resolve this complex issue.

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