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</head><body><p>PS I see that at frequencies around 100MHz ANSI now recommends a lower level than the general 10mW/cm2 used at much higher and lower frequencies. They recommend 0.2mW/cm2, but even at that much lower level recommended as safe for public exposure, you'd still be clear at more than a metre or so away from a dipole radiating a total of 25W<br></p><p><br></p><p>Alex<br></p><blockquote type="cite">On 30 September 2015 at 21:00 Two Lochs Radio <tlr@gairloch.co.uk> wrote:<br><br><p>If the officers know what they are doing, they should be happy with you providing a Declaration of Conformity with ICNIRP with the planning application. Because of the large size of VHF FM antennas, it is quite hard to reach recommended maximum dosage for a 25W erp even at close range.</p><p><br></p><p> <br></p><p>The most common rule of thumb limit for incidental exposure is 10mW/cm2. So for 25W to be safe it only needs to be spread over at least 2500 sq cm or 0.25 sq metres. In other words the whole 25W could be spread across your trunk and would just about reach the recommended maximum. <br></p><p><br></p><p>Of course, the radiation pattern from the antenna is usually 360-degrees around for a dipole, so if you stand to one side, you're unlikely to be able to intercept even a quarter of the radiated power without literally hugging the antenna.</p><p><br></p><p>If you're a glutton for punishment, there is a sophisticated calculator at <a href="http://www.vk3um.com/emr%20calculator.html">http://www.vk3um.com/emr calculator.html</a><br></p><p><br></p><p>Of course, when putting an antenna close (say 50 metres or less) to residential property, a much more likely problem, and one that can cause you a lot of grief or loss of reputation, is interference with the radios or TVs of residents, especially cheapy radios or TVs using indoor antennas. TVs can usually be easily fixed with a cheap filter, but crappy radios can be much more of a problem, even if it is actually the fault of a poorly performing radio rather than your transmission exceeding 110dBuV. <br></p><p><br></p><p>Alex<br></p></blockquote></body></html>