Your new icon is very becoming. Hope it is flush with success.
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My impression of these spreadsheets was that they were of limited use in the near field of an antenna. For example, what worries me is when a family comes and parks themselves beside the stake-down point of my inverted V. So I suppose it’s all to do with just what the E field is doing there and not so much the EIRP of the antenna in the far field. We could do with some specific guidance on this.
I’ve always assumed that at QRP levels the effects of my signals are diminutive compared with environmental influences.
Perhaps it’s all a conspiracy to force us activators to make use of the AZ and not set our gear up right beside the trig point or in another popular areas of a summit!
Joking aside, it would now seem more sensible than ever to make a bit of extra effort to keep out of other people’s way. That’s probably no bad thing.
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Very good Andy - with 6 antennae in use here - some used on up to five different frequency bands from 1.8 MHz to 145 MHz and a capability to run the legal limit on some bands, I will need to produce at least 15 data sheets showing that I am in compliance with the OFCOM safety limits. One out of fifteen now completed!
Sorry, but I don’t think OFCOM would be impressed if you stuck your mobile phone in their faces and asked them to interpret your readings, maybe you were having a joke 
!
The latest RSGB excel spreadsheet calculator (not the orgiinal OFCOM one) is tailored to amateur radio and allows one to select aerial types, band, type of feeder etc from pull down menus. It is helpful in determining the safe distances in metres that OFCOM may wish to see if your station is inspected. In the case of my 2m 7 element yagi, at 10m AGL running the maximum power available 50 watts, using Ecoflex 15 feeder the minimum OFCOM separation to a persons head would be 3.4m. Just out of interest if I were to increase my power to 400 watts the minium OFCOM separation increases to 9.7m. The yagi is horizontally 5.4m from my neighbours garden boundary, therefore if I were to ever run the legal limit I would be outside the safe limit, however if I were to introduce a 3 dB sidelobe loss into the calculation which I understand I am allowed to do, the safe OFCOM separation distance becomes 6.8m to a persons head (1.8m AGL average is assumed for that), so taking into acount the vertical distance of 10m AGL for the yagi I would then be within safe limits.
Where amateurs may find they are likely to be non compliant is where the end of a wire antenna runs up to or along a boundary fence, especially on frequencies below 10 MHz where a different type of calculation is necessary. I haven’t yet done calculations for my other antennae and bands. I supect an 80m band sized OCF dipole I use may not be compliant as the end of it comes within 1.5 metres of an adjoining garden to mine.
This is a very technical field once you you start to delve into it, so having the RSGB calculator at least takes some of the maths (and having to look things up) out of it.
73 Phil G4OBK
Very true Tom, I agree. Our days of operating from shelters on summits could be numbered if there are other folk around talking into their mobile phones and emitting RF into their heads! However I cannot see Mr OFCOM being prepared or even able to follow activators up to the many of the places where activators set up, although I would watch out for them appearing on summits such as The Cloud, Gun or even Bishop Wilton Wold!
73 Phil
Hi Phil
Put the numbers in the spreadsheet last night - and the OfCOM separtions all looked resonable and attainable BUT was more concerned with the red area marked “Near Field Assessment Required”, this could well overlap with SOTA - 40W into a linked dipole on 80m produces a near field zone of 13.1 m. Given the length of a linked dipole that would be a very large part of most AZ’s!
Q) Has anyone tried any of the Near field Modelling yet? Seems to indicate that the issue is the electric and magenetic fields NOT tissue absorbtion below 10MHz.
PS Whilst I can’t imagine that OfCOM will be checking compliance if this became an issue in the media I can imagine both National Parks and the National Trust taking a safety first point of view and if we are not careful banning operations…
73 Paul
I’ll happily challenge any official to a game of “hide and seek” on The Cloud!
… easy with a 2m HH but harder with an 80m linked dipole…
What are these “officials” you speak of? Surely not Ofcom staff out in the field checking on amateurs.
I’ll have an ounce of what you’re smoking please! 
Wouldn’t it be lovely to discuss with OFCOM the niceties of RF exposure on one of these rather exposed summits.
GM/SI-002 Sgurr Dearg - Inaccessible Pinnacle (activations = 2)
GM/SI-214 Stac Lee (activations = 0
GM/SI-204 Stac an Armin (activations = 0)
I think activating these summits is only a dream of glory for normal mortals.
73 de
Andrew G4VFL
Off topic but worth a comment: The West Ridge Route up the In Pin (the route facing the bulk of the mountain) requires a rope run-out of 20 metres and this includes the length of rope used in belaying at the top. As a consequence the col between the In Pin and Sgurr Dearg is inside the AZ so it is possible to activate the summit without climbing the Pinnacle itself, thus avoiding the queue of rock climbers that have been there every time I have climbed Sgurr Dearg! The only time I went equipped to climb the In Pin I gave up after about an hour and a half of waiting my turn and wandered along the main ridge instead. Sgurr Dearg itself is easy(ish) from the campsite in Glen Brittle though it includes some tiresome scree trudging.
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…and midgie dodging 
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No joke Phil - it’s the actual OFCOM spreadsheets stored on my phone (better than carrying dozens of sheets of paper!). I think I’ve done 29 assessments for the various bands and locations (home, high-power SOTA & low-power SOTA).
I haven’t had a chance to look at the RSGB version yet, that’s a project for a quiet weekend. I might just wait a bit until it looks as though they have finalised exactly what we are required to do. I don’t want to keep re-running the assessment everytime they tweak something.
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It’s Phil OBK you need to speak to. He was the one above who suggested that Ofcom people may come lurking on G/SP-015!
Ofcom people couldn’t be bothered to enforce CE markings where there was a possibly of a buck to be made. I can hardly see them worrying about this. I understand Phil’s concern due to him having a bunch of neighbours who wield pitchforks and flaming torches much like the villagers in Young Frankenstein.
I shall do the paperwork anyway.
I’ll be lazy and wait to see if my station matches any of the pre-calculated configurations that the RSGB is preparing.
Ive plugged some data in and as I mainly operate on 2 Meters on low power there seems to be no risk as when Im on a summit I usually have it to myself…
Next thing OFCOM will be expecting us to wear Hi-Viz jackets, hard hats and put cones out when we operate high power on HF…
What is this OFCOM you talk of?
Pedant! 