How To Understand The Kv3Um Electro Magnetic Radiation

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2 Acknowledgements WIA Spectrum Committee Michael Owen.. SK VK3KI.. founder of the modern WIA. Phil Wait VK2ASD [President WIA]. Roger Harrison VK2ZRH [WIA Director]. Peter Young VK3MV [ex Director and ACMA]. Noel Higgins VK3NH [ex ACMA]. (BTW.. I am also a member and ex ACMA).

3 EMR Electro Magnetic Radiation (a more friendly term is EME.. Electro Magnetic Energy) I will address :- The ACMA requirements for the operation of Amateur Radio transmitters. [LCD] The impact this requirement has upon all Amateur antenna installations with respect to EMR. Why this has been raised again with such importance since the LCD first came into force in Why the ACMA said no at the end of the HF HP trial. [LCD].. Radiocommunications Licence Conditions (Apparatus Licence) Determination 2003.

4 Quick Survey if I may! How many present applied for a HF HP permit? How many were asked for a subsequent audit? How many down loaded the ACMA Amateur License conditions [LCD] or referred to them? How many here believe you know what the safe distance is necessary for their Station antennae installation? [to comply with MEL]

5 Myths and rumors heard over the air and seen on various reflectors. Only BIG stations can cause EMR. Incorrect.. We all can exceed MEL at 100 watts [or far less]. Other countries have high power so why cant we? Yes some do.. but most of those have very specific and detailed operating requirements. I will demonstrate if I have time tonight. We need high power for reliable communication [viz Darwin Cyclone Tracy] Maybe.. But I was there in 1974 with a FT 101B! It did good!! The WIA sold out to the ACMA. Totally wrong.. We did our very best and are continuing discussions with the ACMA on LCD and HP matters. Its all a lot of baloney and any way, I really don t care! Well that s an opinion that needs responsible re-focusing!!

6 IT IS NOT THE PERMITTED POWER THAT IS THE REAL ISSUE. IT IS THE SAFETY REQUIREMENTS THAT MUST BE MET WITH THE POWER WE USE.

7 My past [and current] involvement with EMR management. Radio Australia Darwin First EMR measurements. New staff births.. their gender. Applying for a High Power EME permit in Difficulty gaining approval and costs that it incurred resulted in me writing EMRCalc. There was no LCD or precedent at this time and remained this way until 2002/2003. Broadcasting from Stringent EMR requirements. Designation of a RF worker and safety requirements. Site radiation folders. Keeping them up to date.

8 Maintaining calibration of radiation meters. Ever present Linies disregard for EMR safety! A previous study into the high incident of cancer in Artarmon. (NSW) and my involvement with the ITU IEC Committee. Repair and maintenance procedures. How safe is a RF PA to work on? Do we as Amateurs' really know what we are getting into when working with high power amplifiers and high gain antennae? Do our magazines warn of the dangers of high power amplifier construction and alignment?

9 What is RF EME? Electromagnetic energy (EME) is the energy stored in an electromagnetic field. It is a part of our natural environment, emitted by sources like the sun, the Earth and the ionosphere, as well as artificial sources such as mobile phones and base stations, broadcast towers, radar facilities, and electrical and electronic equipment. EME is non-ionising radiation, meaning that it has insufficient energy to break chemical bonds or remove electrons (ionisation). In contrast, ionising radiation (such as X-rays) can remove electrons from atoms and molecules thus leading to damage in biological tissue. Radiofrequency (RF) radiation, which is used mainly for communications purposes, is the transfer of energy by radio waves. RF radiation lies in the frequency range between 3 kilohertz (khz) to 300 gigahertz (GHz). In these fact sheets, RF and RF EME are interchangeable terms..

10 Does exposure to RF EMR cause adverse health effects? THE EPIDEMIOLOGICAL (POPULATION STUDIES) EVIDENCE DOES NOT GIVE CLEAR OR CONSISTENT RESULTS THAT INDICATE THAT EXPOSURE TO RF EME CAUSES DISEASE IN PEOPLE. SOME STUDIES HAVE SHOWN AN ASSOCIATION BETWEEN HEAVY MOBILE AND CORDLESS TELEPHONE USE AND BRAIN CANCER (MOST PRONOUNCED FOR GLIOMA). LIMITATIONS OF THE METHODOLOGY PREVENT CONCLUSIONS OF CAUSALITY BEING DRAWN FROM THESE OBSERVATIONS. MORE RIGOROUS LONG-TERM STUDIES ARE BEING COORDINATED BY THE WORLD HEALTH ORGANIZATION (WHO) AND AUSTRALIA IS TAKING PART IN THIS RESEARCH PROGRAM.

11 All very well with low level EMR but what if EMR exceeds the limit? We all know the effects of a Microwave oven and how it can cook a chook with 800w at 13cm. And that EIRP is easy to generate on 13cm with Amateur equipment and a high gain antennae!

12 Refresher Why is EMR so important. It has the capability to kill or maim you! 2 VK s are known to have received cornea burns as a direct result of their Amateur or professional careers. Ron VK3AKC.. SK Les VK3ZBJ.. SK We have a duty by law to comply with all requirements stipulated in our license conditions.

13 The Australian Communications and Media Authority (ACMA) has the regulatory responsibility to protect the health and safety of persons exposed to RF EME from radiocommunications transmitters. In order to fulfill this regulatory responsibility the then Australian Communications Authority, now ACMA, adopted the ARPANSA limits into the Radiocommunications (Electromagnetic Radiation - Human Exposure) Standard 2003 and the licence conditions for radiocommunications transmitters.

14 EMR Standard The Australian EMR Authority is the Australian Radiation Protection and Nuclear Safety Agency. [ARPNSA] The requirements are no different to the majority of countries through out the World. Some Countries are even more stringent than ourselves. We operate under Part 3 of our ACMA License Conditions (Apparatus Licence) Determination 2003 [LCD] which adds further stipulations to the ARPNSA standard that include :- Tx Power and Antenna accessibility requirements. Additional house keeping requirements if Level 1 is not met and Level 2 compliance is required.

15 ARPNSA STANDARD For RF workers only >> Note Table 7 refers to RMS Electric and Magnetic fields best applicable to the Amateur Service whilst Table 8 refers to Peak fields. For General Public >> 6 minute average total power >> Units are in W/m² >>

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17 ACMA Licensing requirements Part 3 Section 9 (page 8) Level 1 criteria (1) This section applies to a transmitter (other than a mobile station) (a) for which: (i) the average total power supplied by the transmitter to all antennas fed by the transmitter is not more than 100 W; and (ii) each antenna fed by the transmitter is installed so that it is inaccessible to a member of the general public; or (b) for which: (i) the bottom of the lowest antenna fed by the transmitter is at least 10 m above ground level; and (ii) the average total equivalent isotropically radiated power of all antennas fed by the transmitter is not more than 3200 W in any direction; then if either (a) or (b) is met then Level 2 Assessment is not required

18 ACMA Licensing requirements. Part 3 Section 10 (page 9 & 10) Level 2 criteria (1) This section applies to a transmitter to which section 9 does not apply. (2) After 31 May 2003, the licensee must: AS ; and (a) be able to show that the licensee complies with section 8 in relation to the transmitter by: (i) measuring RF fields in accordance with AS ; or (ii) calculating RF fields using a model or method that is derived from the mathematical formulae mentioned in Appendix B to (b) keep records in accordance with section 15. Note for subparagraph (a) (ii) Models or methods include: mathematical modelling computer software programs charts and graphs. (3) If the licensee spatially averages measurements taken for subparagraph (2) (a) (i), the licensee must do so in accordance with section 2.7 of the ARPANSA standard.

19 BBBUT. The over riding requirement is contained in the preceding Part 3 Section 8

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21 In summary Antennae Height and accessibility to the Public If you run an average total power less than 100 watts pm then your antennae must be inaccessible to the Public or the lowest point has to be a minimum of 10 meters above the ground and Your total EIRP must be less than 3200 watts To meet Level 1 criteria.

22 If you run an average total power greater than 100 watts pm then your antennae must be inaccessible to the Public and the lowest point has to be a minimum of 10 meters above the ground and Your total EIRP must be less than 3200 watts To meet Level 1 criteria.

23 What does it really mean? There has not been a change to our licensing requirements Just our interpretation of the safe distance requirement. This was revealed during the HF high power permit application trial. I will now demonstrate the requirements of power and accessibility that effect Amateur Radio installations with the VK3UM EMR Calculator.

24 Changes I made to the VK3UM EMR Calculator to comply with the ACMA requirements. Documents available from

25 Relationship between the transmission mode form factor and the 6 minute period average that determines the average transmitter power. (pm)

26 If less than 100w pm and inaccessible to the public then a 10m minimum antennae height is not required. Less 0.5db transmission loss

27 Greater than 100w pm with antennae inaccessible and a 10m antennae height does not require L2 compliance Less 0.5db transmission loss

28 Greater than 100w pm requires inaccessible to the public and >= 10m min antennae height Less 0.5db transmission loss

29 Level 2 compliance is required but the safe distance is only 3.86m for a tower height of 4.13m