Pay attention to your surroundings whilst engrossed in radio - that’s a new habit I’ll need to perfect…
Are passers by more or less likely to be affected by RF if they are stood with neck craned and open mouthed?
This also means I can’t use members of family as temporary antenna supports unless operating QRP…
Ahh but surely working as an antenna support she’s become an operator working under your supervision/callsign? 
Meanwhile SOTAri from VK and US sigh and shake their heads at all the fuss being made here as they have had to comply with exposure limits for many years.
In the far field the electric and magnetic fields are linked - they are in the ratio of the impedance of free space.
In the near field they haven’t organised themselves together yet. If you stand near a low-impedance part of your antenna (e.g. feed point on a dipole) the field is predominately magnetic. If you move to a high impedance part (e.g. dipole ends) the electric field dominates. Precisely how high that E (or H) field gets will depend on the circumstances. That’s why you need near-field modelling.
The far field formulae are just a simplistic torch-beam type model. What’s the output power? Multiply it by the antenna gain. Apply a 1/r² line-of-site loss to get a power density. This is going to be important for things like a microwave setup, or even UHF. It’s probably appropriate for considering if you are Ok on your home setup if you point your 2-m Yagi at the neighbours’ bedroom. In a SOTA setting if you allow non-involved people to get arbitrarily close to activate parts of your antenna that’s likely to be a near-field question to determine just how bad it is.
Still, my reading of the Ofcom document is that it’s mostly not going to trouble me:
From https://www.ofcom.org.uk/__data/assets/pdf_file/0025/214459/guidance-emf-compliance-enforcement.pdf
6.5 This assessment can be very simple. For example, spectrum users can comply with the EMF
condition if:
a) Their radio equipment never transmits above 10 W EIRP (6.1 W ERP). For example,
radio equipment may not be capable of transmitting above 10 W EIRP (6.1 W ERP) or it
may be set-up or installed in a way which means it cannot transmit above 10 W EIRP
(6.1 W ERP).
My FT-817 will do 5W key down and an inverted V is pretty much isotropic, so 5W EIRP. Ditto on VHF (Ok, maybe the Slim JIM has a little gain over isotropic - about the same as a dipole - so we’re still fine at about 8W EIRP).
By the way, the RSGB spreadsheet imports nicely into Google Sheets. So for my applicable installations I’ll just save that on Google and add a sheet with collected results.
Whilst we’re individually not likely to be approached by Ofcom it is of course necessary to be fully compliant. Perhaps a more likely scenario is being questioned by a member of the public (especially if we start putting “RF Hazard” warnings on our gear!). Of course we are not obliged to respond if he/she demands site of documentation but maybe an especially obstreperous individual might be mollified were you able to show this has all been considered and demonstrated to be compliant to ICNIRP limits.
Updated guidance issued today, including specifically for amateur radio operators:
Looks like joint activations will be OK 
Thanks for this, although I wonder where it leaves those such as me, who operate mainly below 10mhz, and have 99% indoor antennas ?
DAVID
G0FVH.
Cooked?
Happily operating as normal, waiting for further guidance later in 2021
"What do I need to do if my equipment transmits at a frequency lower than 10 MHz?
For the time being, you do not need to do anything for equipment that transmits at frequencies below 10 MHz. We are working on further guidance (which we anticipate publishing later in 2021) and considering whether to extend our EMF calculator to cover these frequencies. We have said that licensees will not need to have records in place demonstrating compliance for such equipment for a year after licences are varies. However, if requested by Ofcom, licensees will need to demonstrate how they comply within 20 calendar days of being asked. However, until we have provided further guidance, we do not expect to start asking licensees to demonstrate how they comply."
I like the example.
So long as we maintain the calculated separation distance apparently we are now allowed to use 142 MHz.
For a lot of us activating from a handheld with an antenna with only one 1/2 wave radiating element this effectively means we just have to write “5W @ 2.15db = 8.2W” on a piece of paper and shove it in our wallet.
With a few days off from work I had a clean out around the shack and stumbled across a document that may be useful information for the fellow radio enthusiast. A bit out of date on the low Freq range but gives a good explanation of the hazards and symptoms at different Freq ranges. I scanned a few pages and uploaded to Google docs Radio Freq Hazards
73
Graeme
Draft UK amateur licence published on Ofcom’s website.
With the many references to near field and far field I wanted a better definition of these terms. I found this article useful …
https://www.everythingrf.com/community/what-are-near-field-and-far-field-regions-of-an-antenna
A couple of points : firstly the transmit duty cycle can be taken into account. This applies to both the average power of the mode used relative to the peak, and also to the Tx/Rx ratio. The spreadsheet takes these into account.
Secondly don’t forget that the operator (you) (and as I understand it any other licensee who is working along with you) is excluded : these limits apply to the “general public”. So if you know the “exclusion zone” for your circumstances (power/mode/antenna) and stop transmitting when anyone comes inside it, then you have also complied.
I wondered how long it would be before this thread on EMF assessments was rekindled! I have still have not received an email notifying me of the neccessity to produce the figures for my station G4OBK. Whatever happened to notifying this sort of thing via the London Gazette?
Just back from a cracking activation of G/TW-002 Cringle Moor and eating a cake I got from the Lord Stones Cafe at the car park with my sandwich back at home. Cinder Road - like Rocky Road but containing more Belgian Chocolate - nice. 63 QSOs with several S2S - best and most productive band was 30m Best DX was K4DY on 20m CW, pretty good to work USA before UK lunchtime. 20m and 40m becoming a little more like summertime condx - I worked Don G0RQL on 40m SSB.
73 Phil
Then either Ofcom don’t have a correct email address for you or your email system deleted it as spam. Either way you should probably contact Ofcom and ask them to clarify the situation rather than moaning about it here.
Ah ah but I’m not moaning about it, wrong, I’m neither dissapointed or glad about it actually. I received an email from OFCOM about a different matter last summer when they kindly responded to a Freedom of Information request to the same email address that I have registered with them, but yes an email to me about the need for an EMF assessment could have gone down a black hole.
Phil
looks better weather than the last time i activated that! Snow, windchill and darkness by 4pm on the walk down in early winter i think it was.
Phil,
Lovely sunny photos, but guessing it must have been cool up there? Not done that route from Lord Stones to G/TW-002 before, and thinking of trying it next time.
On another subject, and just wondering. Have you changed from a KX2 to a KX3, because I thought in a previous post I saw you using a KX2?
73’s
David
HI Dave
Yes, I am enjoying a secondhand KX3 I bought about 5 weeks ago Dave, it is in mint condx and gives a full 15 watts output with a plug in Zippy 4.2 amp LiFEPo 13.8v battery - 10 watts out with my other 12.5v battery (3 X 18650), she throttles back herself when the lower voltage is used. She also came with 8 X NiMH batteries and charger. I sold those on ebay. Very poor output and too heavy for carrying. Even lower voltage with those internal batteries and she throttled back to 5 watts, so not a good option. I bought the KX3 privately with a built in ATU, side plates, roofing filter, 4 amp Tracer battery and charger, KXPD3 paddle and MH3 microphone. I sold on the KXPD3 and MH3 mic as they were of no use to me. Once I got the KX3 I sold my KX2 (without ATU) with sideplates and a home made 18650 battery pack and Loewe case also privately. The chap who sold me the KX3 was buying an IC-705 he isn’t a SOTA player…
Its less than 30 mins walk up from Lord Stones Cafe/free car park. Made it in 25 mins without having to stop, 18 mins down. Very cosy in the sink hole on the south side of the pile of stones out of the wind. Highly recommended!
Enjoy if you go soon but check out the NYCC Traffic website as there is a road closure in Bilsdale on the B road coming up this next week if you are travelling from Helmsley. G4UOK Mike (Gisborough) told me he would be activating TW-002 on Saturday, but the WX forecast looks very wet then if he decides to turn out.
73 Phil
