Mobile telephones, walkie talkies including pmr446 and other small radio transmitters, with some notes on radioactivity, nuclear radiation and failure of the Japanese nuclear power station at Fukushima.


Your safety

By Mike Solomons of London Sound


Latest news - scroll down - at the end you will find some notes on the Fukushima nuclear power plant and its leaking radioactivity - and what they needed to do, (but didn't!).

There are a number of sections below - if you want just scroll down looking at the headings to find items of interest. 

From time to time, the articles in the press on the subject of mobile 'phones interestingly draws attention to some of the details below.  I don't mind, but if they did read this article, (and they should have it drawn to their attention if not), especially as it dates back to the 1980s, it would be nice to see a credit in their published articles.


Mobile Phones


There has been much publicity regarding the safety of mobile telephones, (most of the newspapers have sensationalised these issues at some point). The following brief note hopes to explain the nature of the danger, why it has now emerged, and how to respond sensibly!


At one extreme, we see the 'crazy fringe view' of those who would argue with almost anything, and at the other, those who say everything is OK.  Most of what we read comes from those with a direct financial interest of some kind or another.


And don't be fooled by the word "small" - neither by the size of a modern mobile 'phone nor by any illusion caused by claims of low power - the transmitters contained within these devices are quite powerful enough to be of concern. Just remember that in the hands of an enthusiast, small walkie talkies held in the hand can send their signals hundreds of miles, so the signal when held close to your head is quite capable of causing harm.


So what is the truth?

We all know that very large amounts of electricity can kill. We also know that food in a microwave cooker gets cooked, (and in case you are in any doubt, the microwave cooker cooks with a small radio transmitter - most mobile 'phones also use radio frequencies near to microwaves).

For many years, radio engineers have been warned about the dangers of approaching high power radio transmitter aerials. These dangers were originally made clear by people being burned by touching the aerials of early radio transmitters - a danger also experienced by army personel in the signals sections during world war 11.

We also saw this problem with the origin of the microwave cooker - birds being cooked when flying close to some early radar installations! Yes, it's true - the whole idea of the microwave cooker stems from birds being 'cooked' when they strayed too close to very early high power radar transmitters!

For many years, it had been assumed that small handheld radio transmitters, (conventional walkie talkies), were of such low power that they posed no threat. This was largely true. The early units seemed to pose no discernable threat, as initially such units were very weak, and, due to the radio frequencies used, spread their power over long aerials. For comparison, look at world war 11 backpack radios transmitting with a watt or two into aerials maybe four foot long - or even longer! Children's walkie talkies normally radiate very little power, usually between 10 and 50 mW, and the latest PMR 446 walkie talkies, (keep away from todlers and young children), are restricted to 500 mW - half a watt.

So why is there now perceived to be a threat? Modern portable radio transmitters, (walkie talkies, hand portables, wi-fi, and mobile telephones), are both more powerful than earlier units, (compare most 1980's c.b. radio walkie talkies at up to 100 mW, spread over a three foot aerial, with modern PMR446 radios at 500 mW spread over an aerial often an inch or two long, and peak power from mobiles going into watts). Wi-fi in schools poses a particular problem, as if 30 pupils are all using laptops in a single room, the radiation can be 31 times the agreed safe figure, (include the base transmitter). This suggests that it is relatively easy to exceed the intended safety margins.

The extra danger posed by the use of high power is obvious, but the implications of the shorter aerials need explanation. It's not too difficult - if the aerial is shorter, then the power is more concentrated, and nearer to the unit. Consider the radio signal concentration around your head with a mobile telephone which has an aerial of maybe an inch long, (nowadays usually concealed inside the handset, and held close to you), compared with an older style walkie talkie held in the hand, with a three foot aerial rod - with the aerial rod usually held away from the body.

The danger therefore follows on from this concentration of radio signal radiation. Higher power, a shorter aerial, and it being closer to the body make for a considerably greater risk.

In what way can it harm us? It is a bit like a rough section in a shoe. A rough section in a shoe is barely discernable for a long time, until suddenly you feel pain. Unfortunately, the fear with radio radiation is that the first warning is destruction of body cells, or in the head, brain cells, as well as a cancer risk, with no early warning of pain!

The pain comes later, when the harm has already been caused, and a cancer risk, often ireversible, may now exist.

The danger therefore is that by the time you find out you've been hurt, it may be too late.

The bottom line - do we continue to use radio equipment?

Yes, of course, but with caution. My biggest fear concerns mobile telephones held to the ear, as the aerial is close to the head, providing a highly localised transmitting field cooking part of your brain.

Equally, there is a considerable risk that hands free units using wired earphones may feed the radio signal through the wire to the earphone - which is actually inside your ear! I fear that sometimes this may even pose a greater threat!  We also have to consider which pocket the 'phone is in - are we cooking our hearts, kidneys, lungs or genitals - not a nice choice!

So much for them improving safety!

PMR 446 walkie talkies, security style and police walkie talkies are generally safer, as the aerial is held further from the body in normal use.

However, it is my fear that whilst they are probably safer, some may not be completely 100% safe, especially the higher power professional units which can radiate power measured at many watts, but this also depends on intensity of use.

Be very careful when you are near high power fixed transmitters, for example if you have access to a roof area on a tall building fitted with transmitting aerials. Some of these radiate hundreds of watts - sometimes more!

The danger definitely is related to intensity of use - a five minute call on your mobile is far safer than a two hour gossiping session!  It also assumes sensible use, (imagine a todler putting the "highly chewable" transmitting aerial of a PMR 446 walkie talkie into its mouth, then pressing transmit!).

And don't sunbathe on the office roof next to an aerial transmitting all the time - you may be 'cooked' in more ways than one!

Lower power equipment is much safer. For example, the ordinary home cordless telephone and children's walkie talkies seem to pose no perceivable threat, as they are very much lower power than mobile telephones, and the higher power enthusiast and professional units.

'Keyfob' car door and alarm transmitters are the lowest power devices that we normally handle, so I believe they are completely harmless - some are so low power that ten thousand or more all operating at once would be needed to match the more powerful walkie talkies.

To sum up

Radio radiation can cause harm over a period of time, and usually gives no advance warning. If you use commonly available 'phones and walkie talkies with caution, then, as with any potential risk, you minimise the chance of hurting yourself, without losing the benefit of these modern conveniences. But be warned - and do take care!



We recycle walkie talkies of all kinds, car pmr, cb and amateur radio equipment.  Obviously this is only convenient for those who live near the London Sound shop in Harrow, but proper recycling is definitely preferable to dumping in the rubbish to end as landfill.




We saw in the press in April 2011 that there was an 8" hole in the bottom of a trench at Fukushima through which highly irradiated water was pouring into the sea, (don't eat any Pacific fish unless you have a geiger counter to check it with!).  They tried pouring concrete into it. Plain silly, it just poured through. Then they tried a different liquid sealant.  That also failed.

Why?  With an 8" hole the liquid poured in just poured out again washed away by the irradiated water! 

What's the answer?  Fill some largish containers - maybe very large saucepans at least 12" wide and tall, with rapid setting concrete.  Tip them into the area where the leak is, (they are large enough to get stuck in the hole).  Then put smaller stones also into the hole - maybe crazy paving slabs.  Then add smaller stones as used in concrete.  Finally pour a lot of sand in. That should cause the leak to be largely shut off.  At this point add concrete which, as it can no longer pour out will have time to set.  It would probably help to pour rapid setting additive into the water together with the pumped liquid concrete, (but not pre-mixed, it might block the concrete pouring mechanism).

How did they come to be so stupid as not to be able to work this out?  I think those in charge know how things work and how to run nuclear installations but they are not natural repairers, hence the stupid mistakes.  My idea of large obstructions, medium etc until the water flow has almost stopped then add concrete is any competent repairer's answer, (it's a bit like a gigantic version of a car radiator leak sealant!). Just pouring concrete in never had a chance, leading me to wonder at the stupidity of those in charge who are putting all of us at risk.

Now the original article follows

Nuclear radiation is different from the radio waves radiated from radio transmitters.  I think we have to blame the ancient Romans for that confusion; we derive the relevant words from the Latin word "radio" which literally translates as "I radiate", (but there we go again - "radiate" is derived from "radio"!).

The basic problem seems to be that very few people understand the basics of nuclear radiation.  Let us first distinguish between the radiation itself and items that are radioactive.

A radioactive item sends radiation.  This radiation becomes weaker the further away we go, so that if you hold a nuclear power station fuel rod, this would be the last thing you would do, (the radiation level would prove lethal in a very short time!   On the other hand, if you can see it through a telescope from 50 miles away, it will do you no harm at all.  This means that the direct radiation from Fukushima is no danger at all to the people of Tokyo around 150 miles away. It is also no danger to the rest of the world, it is only a problem for people working at the plant.

If that were the only problem, a large fence with a sign saying "keep out" would be all that was required to resolve the long term difficulties with the power station.

Unfortunately, when the fuel rods get hot, (as they did with the cooling system at Fukushima being out of action), they get very very hot - and radiate physical particles that can be blown in the wind. If they are relatively low, local winds are the main consideration, delivering radioactive particles that look like fine dust, (i.e. not noticeable).  If the dust reaches the upper atmosphere, it gets blown a lot further.  Officially, the nearest that it got to England was Sweden, but I detected a very slightly raised count here in Harrow.  It was marginal - less than you would be likely to experience walking near the nuclear physics department in a hospital, but it was there. It was probably rather higher over parts of America.

The nightmare scenario of a nuclear explosion is, it is claimed, impossible.  I am not convinced, so just regard it as unlikley.  If one of the reactors did blow up, it would probably set the others off, resulting in a very big explosion, and dispersing radioactive dust into the upper atmosphere.

The two biggest fears with this dust, whether from the present catastrope, or the further nightmare of an explosion, is that it will be breathed in and consumed.  Both of these are extremely dangerous in a way that is not easy to understand.  I will, here, attempt to explain-

There is a law of physics called the Inverse Square Law, the maths of which I'll carefully ignore. What it means is that radiation reduces with distance in a way that is not equally as you would expect with distance.

To help to understand the effect, get a small piece of steel and a permanent magnet.  If you place the magnet six inches away, the steel does not move - the radiation of the magnetism is too weak. Move it much closer and there will come a point when the steel item jumps to the magnet. When it's touching, the magnetic force seems very great. In the same way if you have a speck of radioactive dust it might barely register on a meter only an inch away. Open the meter up and put the dust on the detecting device inside and there will be a significant reading. If you could put it inside the detecting device the reading would be much higher.

The danger we fear is that if we ingest a radioactive particle in food or by breathing it into our lungs it is firstly in direct contact, and there is a risk that it will stay, continually causing damage. This particularly applies with radioactive substances that remain radio active for a long time, especially if they will stay a lifetime on entering the lungs. 

Let's look at the main source of radiation at Fukushima, the fuel rods. If encased in a radiation proof shield, there is no danger. If the shield is damaged, radiation comes out in the same way that light would leak out if instead of fuel rods we had a bright light in the chamber.  The danger is intense but only localised.  Radioactive dust can travel the globe, but when we have only tiny dust like specks widely distributed, they represent little risk.  However those close, residents of Tokyo for example, received a lot of the dust in the air, in water, on foodstuffs, so significant amounts got inside their bodies.  The Tokyo residents probably noticed no immediate effect, but I am expecting a small increase in cancers and other radiation induced health problems.  I hope it proves low, or even better, that I am proven wrong, but I doubt it.

As with mobile 'phones and radio transmitters, we have to ask what should we do?  If we continue to have the profit motive allowed to balance risks against cost, there is a chance, in extreme cases, of catastrophic incidents.  However, public ownership is not a perfect answer either, as with the right regulation, the profit motive in privately owned nuclear facilities can see safety that matches or exceeds that of state owned power stations.  The answer has to be truly independent supervision by experts of unquestioned integrity.

There are those who want no nuclear power stations.  That is not a sensible option.  If we closed down just the European nuclear power stations, the rest of the power stations would be insufficient and we would instantly suffer serious power shortages. Serious power shortages would mean hospitals in darkness, failed street lighting and traffic signals - and resultant loss of life.  Alternative power supplies, wind generators as an example, will help but not replace nuclear power.

The answer is simple - we need nuclear power stations that are built and maintained to even better standards than we are used to.  We also have to close down all nuclear power stations that are in "at risk" locations like those near the sea, waterways and in earthquake zones.


Meanwhile, my advice is to regard nil as the only safe level of radiation. Do not visit Tokyo or northern Japan for more than a few days until at least 2020 and if you are there flee as fast and as far as possible.

The same applies to medical procedures involving radioactive substances.  As an example, people with heart disease are often offered investigative scans that use radioactive substances.  Follow these patients through, and the information gained helps the surgeon so the patients' hearts remains ok, but a significant number will die of cancer in the following 20 - 30 years.  A procedure using radioactive sources, dyes etc should only be used where there is an imminent risk of avoidable death.

Radioactivity is a natural and useful part of our world, but best kept at a safe distance!


This leaflet has been prepared by Mike Solomons, based on a lifetime's involvement in these subjects. Did you find this article helpful?  If so, do please ring or email to let me know.  Also, please distribute it as widely as possible, (with acknowledgement of source), so it can help as many people as possible, (see below).

As a further note, you may be interested in Mike's source of expertise in radioactivity. Mike has no relevant qualifications in nuclear radiation, but was trained by Civil Defence in the late 1960s with regard to the possibility of a nuclear war. This training dwelt of radiation's basic transmission through air and the nature and effect of radioactive fallout.  Mike found this interesting and has absorbed further knowledge over the years. His relevant equipment is modest but includes two geiger counters and an ex MOD high level radiation meter.

Please feel free to copy this article about mobile telephones, and other radio equipment, as well as radioactivity and distribute as appropriate.  Mike Solomons owns the copyright on this article which whilst regularly updated, was first written in the 1980s. Mike permits its copying for any purpose, on the sole condition that its source is acknowledged either by simple full copying together with our contact details printed below, or alternatively by partial edited copying, but with our advanced approval of the edited version in writing.


If you found this helpful or if you are going to reprint it, please email  I like to have "feedback" to know how it helps.



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