Danger of RF to pacemakers and other medical devices

[VK4WDM]

For a start, this is not just Wayne dreaming up things after a good batch of weed

The RAAF museum station VK4KG will be operated in a "public environment" - the radio shack at the museum where visitors enter, or "public events"such as the up-coming Catalina memorial event at Bowen.The station runs a maximum of 200w and I have done all the EMF calculations and we will have the correct exclusion zones around the antennas both on-site and in the field.

But to be allowed to operate, the station has to comply with a number of "public safety issues" which would not normally be a worry with a private station. One of the questions being asked is the effect of RF on implanted pacemakers and the other medical devices like the pumps that deliver insulin. One could imagine what could happen if a visitor to the station went into fibrillation and blamed it rightly or wrongly on the RF. Yep, unlikely, but we live in a strange world.

My take on the matter is that, given the number of RF-emitting devices that people come into contact with every day, it is unlikely to be a problem, but I would like to hear what others think, especially those who have pacemakers and the like, and those who have run stations where the public were exposed.

Please - no stupid comments, this is something that I have to provide an answer to.

73

Wayne VKWDM

[VK4WDM]

I just found the follow material from the ARRL, but I would still like more input.

http://www.arrl.org/pacemaker

Wayne VK4WDM

[VK2HRX]

Wayne,

Implantable medical devices such as pace makers and defibs have to comply with a set of standards, some of which are electromedical. These standards specify EMI and EMR. Do a search for these standards and you will find the EMI/EMR specs and then compare these to the specs of the electronics you are operating to gauge if you will have any risks that you may need to mitigate against. The implantable devices will have the specifications declared in their various manuals which is another way to discover them.

PM me if you need any more direction.

Disclosure: I am a member of the Standards Australia HE-019 Committee (covers a large range of medial equipment)

[VK4WDM]

Hi Compton

Thank you for that advice. I Just need to have these things on hand in case the museum management committee needs some hard evidence.

73

Wayne VK4WDM

[VK3DXE]

One of my (least) favourite sayings: "The world is going to ruin on the back of bean counters and risk managers".

[VK5TX]

If you follow the australian standard from ARPANSA. http://www.arpansa.gov.au/pubs/rps/rps3.pdf‎ The non occupational limit is safe for the general public (this includes people with pacemakers and pregnant women).

As the museum is at RAAF Townsville, 452SQN should have Defence Radio Frequency Safety Officer (DRFSO) and the equipment to measure the RF exposure limits.

Ben

[VK3BSF]

Go to the following WIA site

http://www.wia.org.au/members/technical/emr/

and download the EMR Site Radiation calculations..input your power, antenna and get the safe Radiation Limit distances for your site. u can print out and show the Co/radiation officer your results against the safe limits for medical devices (which u will need to get).

VK3UM EMRCalc Ver 7.07
VK3UM EMRCalc Ver 7.07 Install.zip

[VK3KTO]

Greetings all.
As a matter of interest my XYL has had a pacemaker fitted for some time and has not reported any ill effects from my radio activities. I can run 400 watts on hf and 150 watts on 2 metres and have used the VK3UM program and it it gives me the OK.
73 de Mike VK3KTO

[VK3ART]

One of my (least) favourite sayings: "The world is going to ruin on the back of bean counters and risk managers".

Alan, I'm a Risk Manager !!
Russ VK3ART

[VK3MV]

Wayne
The Commonwealth Therapeutic Goods Administration (TGA) is the responsible government agency that regulates medical device which includes heart pace- makers. The issue is the how imune a device is the RF field in the near proximity. The TGA mandates standards for safe working of devices, so that is where I would go to seek reliable information. See: http://www.tga.gov.au/

Peter VK3MV

[VK4UH]

Hi Guys

Radio hobby here is funded by career as Medical Specialist trained as a Cardiothoracic Anaesthetist and in Intensive Care.

Just some further background on RF and pacemakers particularly for fellow hams who might have one of these already implanted. As suggested earlier in the string the modern design of these unit makes them very well "immunised" against most external RF fields, certainly as would be found in the average ham station complying with EMR (and some!).

They are still however susceptible to external fixed magnetic fields ie from fixed magnets which should be avoided. This is because they all deliberately have magnetic switches in them to allow people like me to change their function and mode with a magnet applied to the pacemaker through the skin. For example under general anaesthesia and surgery when RF diathermy current is used directly through body tissue.

Careful note however this advice DOES NOT APPLY to AICD automatic Implanted Cardiac Defibrillators (implanted defibrillators) which are becoming far more common. These devices are much less well protected against and external RF or any form of AC electrical interference. If you have one of these then you do need to be extra vigilant about avoiding large RF fields or contact with even modest 50Hz voltages as they will "FIRE" and shock you with a very low threshold of signal - as they are supposed to do

73 Kevin VK4UH
Dr Kevin Johnston MB BCH, FFARCS, FRCA, FANZCA
Specialist Anaesthetist

[VK2XSO]

If you're below the ARPANSA public exposure limits (which are very low) I would tend to think that they have already conducted some sort of research or based those public exposure limits with such medical implants in mind. Public exposure is meant to cover everybody, including all foreseeable problems.

I don't have a pacemaker, but I have a few other pieces of metal in my person. I undergo a medical every two years now. I can't get any of the doctors to take an interest in my resonant properties.
They take one look at the scars and say, "eh, that'll be fine !"

So as far as metalic implants go with regards to fractures; I've had doctors for 20 years say there is nothing to worry about even as an RF worker.

[ZL2FAE]

Wayne

Err on the side of caution.
I understand that Australia is particularly litigious so I would suggest seeking approval to operate with the proviso that you:
1) Post multiple hazard signs warning people with medical implants, etc that to enter the "zone" could be hazardous to their health and is done at their own peril.
2) Have ushers advising every person enteing the "zone" about the risks and obtaining their sign off of understanding and confirming they have no medical implants.

Sounds crazy..... yep it is, but this is now the tone of the world we live in.

[VK4UH]

further to my previous posting

There IS NO ISSUE with RF exposure on metallic medical implants like hip or knee replacements_ totally and I mean totally safe

What is being discussed are electronic implants like pacemakers, AICS or I suppose cochlear implants.

see my earlier post today

Dr Kevin Johnston VK4UH

[VK3ZAZ]

I just found the follow material from the ARRL, but I would still like more input.

http://www.arrl.org/pacemaker

Wayne VK4WDM

Wayne somewhere years ago this has been hashed and rehashed.

It was proven that the rf field to stop a pacemaker wold be very intense.

I dont know of any cases in USA where we run 1500 watts that pacemaker has stopped by a ham transmission.

But I notice on the TESLTRA exchange on my site a PACEMAKER and MEDICAL IMPLANT Warning sign

whichTELSTRA do not put on country exchange fences inside town boundaries FWIW.

Only out of towns, dont know why thats the case.

I just did a recalc after the stuff up with the emr program announced last weekend and find my 1000 watts into 10db at 25 metres is still CLASS 1 compliant.
A are my HF Triband and HF 1KW.

I do not as a matter of course run 1KW on dipoles on 80 and 40 whic is more than I can say for others in this country.

I THINK dipoles have to be 10M agl at ends correct me if I am wrong.

if we put a sign on yourgate saying anyone with a medical implant dont enter I think we will be asking for trouble.


FWIW I am onsite today and have towo guys climbing the tower

They will pass within 2 metres of the fm stack of dipoles andI have to wind down the FM transmitters from 100kw to 3%

3KW and they are wearing stainless threaded rf suits.

The rule is DONT GET EXPOSED
DONT OPEN VHF TV PAS and run power through them
Dont mess with unshileded RF at any level

and you might live to a ripe old age like me..
BCAST ch since 1969 everything from 400 to 50000 watts MF and 100,000 VHF 1000000 UHF.

Healhy as a mallee bull cough cough spluuter spit...

[VK4WDM]

OK, thank you for all the material, especially from Kevin VK4UH. I will stick it in a file so I can haul it out when the museum undergoes an audit by the ADF safety cell.

We have done the EMR compliance measurements and doubled the exclusion zone around the antennas just to make sure.

Hope you all work VK4KG in the RD contest.

73

Wayne VK4WDM