Re: EMC in the news: RFID & Medical

[John Woodgate]

In message <380-2200872113338...@earthlink.net>, dated Tue, 1 Jul 2008, 
Cortland Richmond  writes:


>I am coming to this late, but this is in line with results for LF 
>security devices versus implanted cardiac defibrillator/pacemakers, is 
>it not?

I don't think we have enough information to say. The whole field (pun!) 
is characterized by missing data.
-- 
OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk
Either we are causing global warming, in which case we may be able to stop it,
or natural variation is causing it, and we probably can't stop it. You choose!
John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

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Re: EMC in the news: RFID & Medical

[Cortland Richmond]

I am coming to this late, but this is in line with results for LF security
devices versus implanted cardiac defibrillator/pacemakers, is it not?

Cortland
KA5S


> [Original Message]
> From: E. Robert Bonsen 
> To: 
> Date: 6/26/2008 5:39:08 PM
> Subject: Re: EMC in the news: RFID & Medical
>
> Published in the Journal of the American Medical Association:
>
> http://jama.ama-assn.org/cgi/content/short/299/24/2884
>
> $15 to download the article.
>
>
>  From the summary, no real info on the test process:
>
> *Design and Setting * Without a patient being connected,^ EMI by 2 RFID 
> systems (active 125 kHz and passive 868 MHz) was^ assessed under 
> controlled conditions during May 2006, in the^ proximity of 41 medical 
> devices (in 17 categories, 22 different^ manufacturers) at the Academic 
> Medical Centre, University of^ Amsterdam, Amsterdam, the Netherlands. 
> Assessment took place^ according to an international test protocol. 
> Incidents of EMI^ were classified according to a critical care adverse 
> events^ scale as hazardous, significant, or light.
>
>
> Regards
> --Robert
>
> E.Robert Bonsen
> Sr. Engineer
> Orion Scientific

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Re: EMC in the news: RFID & Medical

[pat.lawler]

Hi John: 

No, the article doesn't mention field strength.  However, the test procedure
is one I'm not familiar with: 
   ANSI C63.18-1997, 'American national standard recommended practice for an
on-site, ad hoc test method for 
   estimating radiated electromagnetic immunity of medical devices to specific
radio-frequency transmitters' 
In short, they vary the separation between the RFID device and the medical
equipment from 600 cm (20 feet) down to 0 cm (touching the equipment case),
and record the distance where the equipment failed.  Random RFID devices,
random power levels, with a test distance down to zero? 

I appreciate RFID interference is something to be considered.  However, it's
not fair to compare the immunity standard used in the report, to the pass/fail
testing with the fixed amplitude/fixed distance conditions in present IEC
immunity tests (mentioned elsewhere in the email thread.) 

Pat Lawler
EMC Engineer
SL Power Electronics Corp.

John Woodgate  wrote on 06/27/2008 09:28:20 AM:
> In message ,
> dated Fri, 27 Jun 2008, "Dean Gerard (Medical Physics)"
>  writes:
> >
> >Whilst I've seen the original article (Journal of the American Medical
> >Association), unfortunately I can't circulate it without breaking our
> >subscription license agreement.

> Thanks for the information you have given, anyway. The elephant in the
> room is the field strength information. Is there anything about that in
> the paper?
> --
> OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk
> Either we are causing global warming, in which case we may be able to stop
it,
> or natural variation is causing it, and we probably can't stop it. You
choose!
> John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK -
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RE: EMC in the news: RFID & Medical

[Conway, Patrick R (Houston)]

 
This is great information.  
Thank you for providing some details.  
 
The comment: "had an 868-MHz reader (2-4 W). "  is informative.  It
indicates that the RFID was not the only transmitter in the proximity of the
medical EUT.  This RFID reader adds another parameter that requires control
and investigation during the test.  
 
continuing the list of possibilities:
 
f)  is it possible that the RFID tag has much less effect than that of the
RFID reader?
Would be informative to find out if the RFID reader, in the absence of the
tags themselves, can duplicate any of the EUT problems.

 

Best Regards, 

Patrick. 
p.con...@hp.com 

 




From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Dean Gerard
(Medical Physics)
Sent: Friday, June 27, 2008 11:48 AM
To: emc-p...@ieee.org
Subject: FW: EMC in the news: RFID & Medical






Just nominal power outputs and separation distances between interfering and
susceptible equipment. 

Output info given is - 
 "The passive RFID system selected for this study (OBID, Feig Electronic,
Weilburg, Germany) had an 868-MHz reader (2-4 W). The active RFID system

(Eureka RFID, Avonwood, England) had a 125-kHz reader (68_10E-3 µT at 1m)
that forces tags to transmit in its proximity. The active RFID tag had an
operational frequency of 868 MHz at 2 µW"

Interference effects were provoked at separation distances ranging from 5 -
600cm, depending upon equipment affected. 



Ged Dean 
Nottingham University Hospitals NHS Trust 

 

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Re: EMC in the news: RFID & Medical

[John Woodgate]

In message , 
dated Fri, 27 Jun 2008, "Dean Gerard (Medical Physics)" 
 writes:


>Whilst I've seen the original article (Journal of the American Medical 
>Association), unfortunately I can't circulate it without breaking our 
>subscription license agreement.

Thanks for the information you have given, anyway. The elephant in the 
room is the field strength information. Is there anything about that in 
the paper?
-- 
OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk
Either we are causing global warming, in which case we may be able to stop it,
or natural variation is causing it, and we probably can't stop it. You choose!
John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

-

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RE: EMC in the news: RFID & Medical

[Dean Gerard (Medical Physics)]

  

Whilst I've seen the original article (Journal of the American Medical
Association), unfortunately I can't circulate it without breaking our
subscription license agreement.

The investigation was apparently commissioned by the Dutch Ministry of Health. 

Standard they refer to is - 

American National Standard Recommended Practice for On-site Ad Hoc Test Method
for Estimating Radiated Electromagnetic Immunity of Medical Devices to
Specific Radio-frequency Transmitters (Standard C63.18). (AAMI:/ IEEE; 1997).

(not a rigorous EMC product test standard - but rather a suggested basic
methodology for equipment users to investigate possible EMI in a consistent
way)


The project was apparently driven by the search for a system to monitor blood
products, which influenced their choice of RFID systems to test, as follows -

"The selection of 2 RFID systems tested in this study was based on 3
characteristics: (1) the systems needed to comply with RFID standards set by
the European Telecommunications Standards Institute; (2) radio frequencies
needed to fall within the most common internationally used RFID frequency
bands and (3) performance needed to fulfill the operational requirements of
the project including availability of temperature sensitive RFID tags,
low-cost tags suitable for disposable materials, contemporary integration with
the local communications network, and location accuracy within a health care
facility."

Tests were performed in a 1-patient room, free of reflective objects, based
upon methodology in the standard above. 


Ged Dean 
Nottingham University Hospitals NHS Trust 


___
_ 

-Original Message- 
From: emc-p...@ieee.org [mailto:emc-p...@ieee.org <mailto:emc-p...@ieee.org> ]
On Behalf Of John Woodgate 
Sent: 27 June 2008 08:29 
To: emc-p...@ieee.org 
Subject: Re: EMC in the news: RFID & Medical 

In message <48640ca5.3060...@orionscientific.com>, dated Thu, 26 Jun 2008, E.
Robert Bonsen  writes:


>Assessment took place^ according to an international test protocol. 

Really? Don't they cite the reference? I don't know of one that covers 
125 kHz and 868 MHz. 
-- 
OOO - Own Opinions Only. Try www.jmwa.demon.co.uk
  and www.isce.org.uk   
Either we are causing global warming, in which case we may be able to stop it, 
or natural variation is causing it, and we probably can't stop it. You choose! 
John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK 

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Re: EMC in the news: RFID & Medical

[John Woodgate]

In message <48640ca5.3060...@orionscientific.com>, dated Thu, 26 Jun 
2008, E. Robert Bonsen  writes:


>Assessment took place^ according to an international test protocol.

Really? Don't they cite the reference? I don't know of one that covers 
125 kHz and 868 MHz.
-- 
OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk
Either we are causing global warming, in which case we may be able to stop it,
or natural variation is causing it, and we probably can't stop it. You choose!
John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

-

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RE: EMC in the news: RFID & Medical

[Gert Gremmen]

 

TNO made a suggestive title by referring to RFID devices, where most problems
are induced by only 2 of the available systems. Probably to draw more
attention for their article, and they succeeded.

TNO is a Netherlands institute for applied science and have been forced to
change their way of being financed from public to private.

 

Apparently, most of the problems occur with high power 868 MHz backscatter
RFID systems. These are conditionally allowed to transmit up to 3.8 watts EIRP
(Friss tells us that that might be up to  50 V/m ) For frequency power
allocations in NL :

 

http://www.agentschaptelecom.nl/nfr/main_nfr_uk.html

 

This is close to  the  GSM-standard and power range, and we all know that
these devices are to be used with care (forbidden) in medical environments.

 

These RFID’s  are definitely not the items we usually use as RFID such as 
Legic, Mifare or other low power RFID systems.

The article should therefore be read as a warning against high power RFID
backscatter technologies.

While we can discuss about if  Medical equipment should or should not be
immune to this field strength, we may discuss the suitability of these 868 MHz
backscatter radar type RFID systems,  in medical and  residential 
environments where fields of 3 or maximum 10V/m should be expected.

I wonder btw how this allowance of  2W ERP (3.8 W EIRP) got into the European
frequency tables. Maybe because the power and frequency are close to GSM. Not
taking into account the much closer operating distance that goes with RFID.

 

For the time being we will have to live with RFID technologies  that interfere
with medical (and other) electronics, until the  standards committees again 
noticed their lag on technology. and raise the immunity levels to  50 V/m or
more.

 

(EN 55024  for example still uses 3V/m and limits the test range to 1 GHz only
, where 1.8 GHz GSM are used all over Europe, and even higher frequency UMTS
systems are being rolled out: new problems are to be expected!)

 

Regarding the discussion: both interfering RFID systems should not be
‘simulated’ with the EN 6100-4-6 method, as the 125 kHz is below it’s 
f-limits (and would go unnoticed), and the other is way above it’s upper
f-limits (80  or 230 MHz)

 

 

Gert Gremmen

ce-test, qualified testing bv

 

Van: emc-p...@ieee.org [mailto:emc-p...@ieee.org] Namens Ken Javor
Verzonden: Friday, June 27, 2008 12:57 AM
Aan: Untitled
Onderwerp: Re: EMC in the news: RFID & Medical

 

None of the below.  61000-4-3 specified rf source impedance is 150 Ohms,
calibrated into 150 Ohms load impedance. The 1, 3, and 10 Volt levels are
open-circuit quantities, thus the potential developed in the matched load is
one-half the limit.  The current flowing on a cable under test will depend on
the cable impedance, which is not controlled, except on the AE side, because
the injection device is designed to insert a high common mode impedance on the
AE side of the cable (high relative to 150 Ohms).  As far as I know, you do
not measure injected current doing the test this way.  There is an alternative
current injection test when a suitable coupling device is not available, but
then you inject and measure current, not rf potential.  The current limit is
the short circuit current available from the open circuit potential limit
divided by the 150 Ohm source impedance, even though you will not have a 150
Ohm source impedance when injecting current.
 
Ken Javor

Phone: (256) 650-5261





From: Daniel Roman 
List-Post: emc-pstc@listserv.ieee.org
List-Post: emc-pstc@listserv.ieee.org
List-Post: emc-pstc@listserv.ieee.org
Date: Thu, 26 Jun 2008 17:53:59 -0400
To: Ken Javor , Untitled 
Conversation: EMC in the news: RFID & Medical
Subject: RE: EMC in the news: RFID & Medical

While slightly off-topic, this discussion got me thinking about the
measurement of the voltage on the cable.  If done with a RF cable current
clamp, do you have to do a conversion of some sort if the cable is assumed to
be 150 ohms?
 
For a 50 ohm system, a 3V level measured with a clamp would be 96 dBuA minus
the transfer impedance in dB ohms.  If the cable is 150 ohms though does that
mean you are measuring the equivalent of 1V from the clamp instead of 3V
because the clamp is measuring current?  Stated another way, assuming the
transfer impedance of the current clamp is zero to simply things, for an
assumed 150 ohm cable should you be reading 96 dBuV on a spectrum analyzer
hooked up to the probe or something less that than equivalent to 1V?
 
Never worked with this stuff so I’m curious.
 
Dan
 

From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Ken Javor
Sent: Thursday, June 26, 2008 11:14 AM
To: Untitled
Subject: Re: EMC in the news: RFID & Medical

Comment (e) is unrealistic.  Assuming 61000-4-6 was applied, the amount of
power required to directly inject 1, 3 or 10 Volts oc into 150 Ohms is well
above the radiated power from an rf id de

Re: EMC in the news: RFID & Medical

[Ken Javor]

None of the below.  61000-4-3 specified rf source impedance is 150 Ohms,
calibrated into 150 Ohms load impedance. The 1, 3, and 10 Volt levels are
open-circuit quantities, thus the potential developed in the matched load is
one-half the limit.  The current flowing on a cable under test will depend on
the cable impedance, which is not controlled, except on the AE side, because
the injection device is designed to insert a high common mode impedance on the
AE side of the cable (high relative to 150 Ohms).  As far as I know, you do
not measure injected current doing the test this way.  There is an alternative
current injection test when a suitable coupling device is not available, but
then you inject and measure current, not rf potential.  The current limit is
the short circuit current available from the open circuit potential limit
divided by the 150 Ohm source impedance, even though you will not have a 150
Ohm source impedance when injecting current.
 
Ken Javor

Phone: (256) 650-5261





From: Daniel Roman 
List-Post: emc-pstc@listserv.ieee.org
List-Post: emc-pstc@listserv.ieee.org
List-Post: emc-pstc@listserv.ieee.org
Date: Thu, 26 Jun 2008 17:53:59 -0400
To: Ken Javor , Untitled 
Conversation: EMC in the news: RFID & Medical
Subject: RE: EMC in the news: RFID & Medical

While slightly off-topic, this discussion got me thinking about the
measurement of the voltage on the cable.  If done with a RF cable current
clamp, do you have to do a conversion of some sort if the cable is assumed to
be 150 ohms?
 
For a 50 ohm system, a 3V level measured with a clamp would be 96 dBuA minus
the transfer impedance in dB ohms.  If the cable is 150 ohms though does that
mean you are measuring the equivalent of 1V from the clamp instead of 3V
because the clamp is measuring current?  Stated another way, assuming the
transfer impedance of the current clamp is zero to simply things, for an
assumed 150 ohm cable should you be reading 96 dBuV on a spectrum analyzer
hooked up to the probe or something less that than equivalent to 1V?
 
Never worked with this stuff so I’m curious.
 
Dan
 

From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Ken Javor
Sent: Thursday, June 26, 2008 11:14 AM
To: Untitled
Subject: Re: EMC in the news: RFID & Medical

Comment (e) is unrealistic.  Assuming 61000-4-6 was applied, the amount of
power required to directly inject 1, 3 or 10 Volts oc into 150 Ohms is well
above the radiated power from an rf id device. 
Ken Javor

Phone: (256) 650-5261




From: "Conway, Patrick R (Houston)" 
List-Post: emc-pstc@listserv.ieee.org
List-Post: emc-pstc@listserv.ieee.org
List-Post: emc-pstc@listserv.ieee.org
Date: Thu, 26 Jun 2008 14:17:00 +
To: Gert Gremmen , "Rudd, Adam"
, "emc-p...@ieee.org" 
Conversation: EMC in the news: RFID & Medical
Subject: RE: EMC in the news: RFID & Medical

Gert-
You mention one possible reason for the test results is that the EUT's
have immunity deficits.
  I agree, that is one possibility.  

  here are a few other possibilities:   
(BTW- not affiliated in any way with medical devices nor with, all
comments OOO )

 
b)Could it be a systemic testing error?
Was a shield room used?   
Were the ambients controlled and eliminated?
Were the devices connected to a patient simulator?
Did the test engineer have his personal GSM phone "OFF"?  etc. 
(...crazier things have happened.)

 
c)Maybe the EUT are old.
Through outdated design specs perhaps RFID proximity was not a
consideration during their design.
  And yet, in today's hospitals, the two types of devices may be in
close proximity.
  If this is the case then the study has done a great service to the
community by uncovering a problem that was unknown.

 
d)Maybe the EUT are old (not a repeat) 
  Through many years of use perhaps once immune equipment has lost
some of their designed immunity?
  Again- if this is the case this study may have uncovered a
previously unknown problem.


e)Is it possible for an RF ID device to overwhelm the immunity levels of
the EUT?
If a medical device is tested at 10 V/m and an RFID device TXout is in
the mW range- is it possible for a RFID mW transmitter to generate 10 V/m?
Perhaps.
For instance- since an RFID device operating at 125 kHz in not
transmitting in the classic sense, then there may be near-field resonant
effects that are not previously understood in the medical device immunity
requirements?
   

 
  It seems that we, as professionals in this field, have the unique ability to
analyze these reports like no other community can.  I wonder if we will find
the answers to the large number of questions raised by the article.  

 
 
All comments OOO.
Best Regards, 

Patrick. 
p.con...@hp.com 

  

__

RE: EMC in the news: RFID & Medical

[Daniel Roman]

While slightly off-topic, this discussion got me thinking about the
measurement of the voltage on the cable.  If done with a RF cable current
clamp, do you have to do a conversion of some sort if the cable is assumed to
be 150 ohms?

 

For a 50 ohm system, a 3V level measured with a clamp would be 96 dBuA minus
the transfer impedance in dB ohms.  If the cable is 150 ohms though does that
mean you are measuring the equivalent of 1V from the clamp instead of 3V
because the clamp is measuring current?  Stated another way, assuming the
transfer impedance of the current clamp is zero to simply things, for an
assumed 150 ohm cable should you be reading 96 dBuV on a spectrum analyzer
hooked up to the probe or something less that than equivalent to 1V?

 

Never worked with this stuff so I’m curious.

 

Dan

 

From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Ken Javor
Sent: Thursday, June 26, 2008 11:14 AM
To: Untitled
Subject: Re: EMC in the news: RFID & Medical

 

Comment (e) is unrealistic.  Assuming 61000-4-6 was applied, the amount of
power required to directly inject 1, 3 or 10 Volts oc into 150 Ohms is well
above the radiated power from an rf id device. 
Ken Javor

Phone: (256) 650-5261





From: "Conway, Patrick R (Houston)" 
List-Post: emc-pstc@listserv.ieee.org
List-Post: emc-pstc@listserv.ieee.org
List-Post: emc-pstc@listserv.ieee.org
Date: Thu, 26 Jun 2008 14:17:00 +
To: Gert Gremmen , "Rudd, Adam"
, "emc-p...@ieee.org" 
Conversation: EMC in the news: RFID & Medical
Subject: RE: EMC in the news: RFID & Medical

Gert-
You mention one possible reason for the test results is that the EUT's
have immunity deficits.
   I agree, that is one possibility.  

   here are a few other possibilities:   
(BTW- not affiliated in any way with medical devices nor with, all
comments OOO )

 
b)Could it be a systemic testing error?
Was a shield room used?   
Were the ambients controlled and eliminated?
Were the devices connected to a patient simulator?
Did the test engineer have his personal GSM phone "OFF"?  etc. 
(...crazier things have happened.)

 
c)Maybe the EUT are old.
Through outdated design specs perhaps RFID proximity was not a
consideration during their design.
   And yet, in today's hospitals, the two types of devices may be in
close proximity.
   If this is the case then the study has done a great service to the
community by uncovering a problem that was unknown.

 
d)Maybe the EUT are old (not a repeat) 
   Through many years of use perhaps once immune equipment has lost
some of their designed immunity?
   Again- if this is the case this study may have uncovered a
previously unknown problem.


e)Is it possible for an RF ID device to overwhelm the immunity levels of
the EUT?
If a medical device is tested at 10 V/m and an RFID device TXout is in
the mW range- is it possible for a RFID mW transmitter to generate 10 V/m?
Perhaps.
For instance- since an RFID device operating at 125 kHz in not
transmitting in the classic sense, then there may be near-field resonant
effects that are not previously understood in the medical device immunity
requirements?
   

 
   It seems that we, as professionals in this field, have the unique ability
to analyze these reports like no other community can.  I wonder if we will
find the answers to the large number of questions raised by the article.  

 
 
All comments OOO.
Best Regards, 

Patrick. 
p.con...@hp.com 

 



From: Gert Gremmen [mailto:administra...@ce-test.info] 
Sent: Thursday, June 26, 2008 2:57 AM
To: Conway, Patrick R (Houston); Rudd, Adam; emc-p...@ieee.org
Subject: RE: EMC in the news: RFID & Medical

The report was produced by TNO, a Dutch private organization
(http://www.tno.nl/content.cfm?&context
markten&content=markt_persbericht&laag1=189&item_id=200806250026&Taal=2
<http://www.tno.nl/content.cfm?&con
ext=markten&content=markt_persberic
t&laag1=189&item_id=200806250026&Taal=2>
<http://www.tno.nl/content.cfm?&context
markten&content=markt_persbericht&laag1=189&item_id=200806250026&Taal=2>  )
 
and some results are available here:
 
http://www.amc.nl/?pid=5266
 
Manufacturers name and equipment type included.
 
Please note that the energy levels of RFID are in the milliwatt range,
so all problems are to be categorized as immunity deficits.
 
 
It is astonishing that the security of healthy persons (like car drivers) 
is taken much more seriously (by car manufacturers for example )
as the security  of people with bad health like in hospitals.
Most medical equipment is tested  at 10 V/meter or less.
where critical car parts must  be tested up to 200V/m.
 
Cars are to be sold at low 

Re: EMC in the news: RFID & Medical

[E. Robert Bonsen]

Published in the Journal of the American Medical Association:

http://jama.ama-assn.org/cgi/content/short/299/24/2884

$15 to download the article.


 From the summary, no real info on the test process:

*Design and Setting * Without a patient being connected,^ EMI by 2 RFID 
systems (active 125 kHz and passive 868 MHz) was^ assessed under 
controlled conditions during May 2006, in the^ proximity of 41 medical 
devices (in 17 categories, 22 different^ manufacturers) at the Academic 
Medical Centre, University of^ Amsterdam, Amsterdam, the Netherlands. 
Assessment took place^ according to an international test protocol. 
Incidents of EMI^ were classified according to a critical care adverse 
events^ scale as hazardous, significant, or light.


Regards
--Robert

E.Robert Bonsen
Sr. Engineer
Orion Scientific

-

This message is from the IEEE Product Safety Engineering Society
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Re: EMC in the news: RFID & Medical

[John Woodgate]

In message 
, 
dated Thu, 26 Jun 2008, pat.law...@slpower.com writes:


>Unfortunately, the printed report doesn't seem to be available at that 
>address.  I was hoping to read a computerized translation of the 
>report, as poor as that might be.

Go to the URL and towards the right,  at the top of the page, there is a 
link 'Nederlands'. Click on that.

Good luck with your computer translation: it's liable to be Double 
Dutch. What clearly aren't there are the magic symbols 'dB(μV/m)'.
-- 
OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk
Either we are causing global warming, in which case we may be able to stop it,
or natural variation is causing it, and we probably can't stop it. You choose!
John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

-

This message is from the IEEE Product Safety Engineering Society
emc-pstc discussion list.Website:  http://www.ieee-pses.org/

To post a message to the list, send your e-mail to emc-p...@ieee.org

Instructions:  http://listserv.ieee.org/request/user-guide.html

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 Scott Douglas   emcp...@ptcnh.net
 Mike Cantwell   mcantw...@ieee.org

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 David Heald:emc-p...@daveheald.com

All emc-pstc postings are archived and searchable on the web at:

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[SPAM] RE: EMC in the news: RFID & Medical

[Grasso, Charles]

Patricks point is well taken with regard to old equipment. However, if the
medical equipment is functioning as designed
then this throws the entire Medical Device Directive ( and all of its
associated immunity
testing) into question does it not?

 

After all when we test a unit for immunity the levels are typically orders of
magnitude
higher than any *emitted* noise.

 

Interesting!

 



From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Conway,
Patrick R (Houston)
Sent: Thursday, June 26, 2008 8:17 AM
To: Gert Gremmen; Rudd, Adam; emc-p...@ieee.org
Subject: RE: EMC in the news: RFID & Medical

 

Gert-

You mention one possible reason for the test results is that the EUT's
have immunity deficits.

I agree, that is one possibility.  

 

here are a few other possibilities:   

(BTW- not affiliated in any way with medical devices nor with, all
comments OOO )

 

 

b)Could it be a systemic testing error?

Was a shield room used?   

Were the ambients controlled and eliminated?

Were the devices connected to a patient simulator?

Did the test engineer have his personal GSM phone "OFF"?  etc. 
(...crazier things have happened.)

 

 

c)Maybe the EUT are old.

Through outdated design specs perhaps RFID proximity was not a
consideration during their design.

And yet, in today's hospitals, the two types of devices may be in
close proximity.

If this is the case then the study has done a great service to the
community by uncovering a problem that was unknown.

 

 

d)Maybe the EUT are old (not a repeat) 

Through many years of use perhaps once immune equipment has lost
some of their designed immunity?

Again- if this is the case this study may have uncovered a
previously unknown problem.

 



e)Is it possible for an RF ID device to overwhelm the immunity levels of
the EUT?

If a medical device is tested at 10 V/m and an RFID device TXout is in
the mW range- is it possible for a RFID mW transmitter to generate 10 V/m?

Perhaps.

For instance- since an RFID device operating at 125 kHz in not
transmitting in the classic sense, then there may be near-field resonant
effects that are not previously understood in the medical device immunity
requirements?

   

 

 

It seems that we, as professionals in this field, have the unique ability
to analyze these reports like no other community can.  I wonder if we will
find the answers to the large number of questions raised by the article.  

 

 

 

All comments OOO.

Best Regards, 

Patrick. 
p.con...@hp.com 

 

 



From: Gert Gremmen [mailto:administra...@ce-test.info] 
Sent: Thursday, June 26, 2008 2:57 AM
To: Conway, Patrick R (Houston); Rudd, Adam; emc-p...@ieee.org
Subject: RE: EMC in the news: RFID & Medical

The report was produced by TNO, a Dutch private organization

(http://www.tno.nl/content.cfm?&context
markten&content=markt_persbericht&laag1=189&item_id=200806250026&Taal=2)

 

and some results are available here:

 

http://www.amc.nl/?pid=5266

 

Manufacturers name and equipment type included.

 

Please note that the energy levels of RFID are in the milliwatt range,

so all problems are to be categorized as immunity deficits.

 

 

It is astonishing that the security of healthy persons (like car drivers) 

is taken much more seriously (by car manufacturers for example )

as the security  of people with bad health like in hospitals.

Most medical equipment is tested  at 10 V/meter or less.

where critical car parts must  be tested up to 200V/m.

 

Cars are to be sold at low prices (relatively) , medical equipment

at sky-high costs.  It seems that emc quality is the inverse of the

costs of equipment. Where much attention is given to

reliability and electrical safety of medical equipment,

emc is still  neglected. 

Note that this investigation was made in a Dutch

University Hospital;

On  European soil , where immunity requirements have been 

virtually law since 1996 

 

The lack of EMC care might be related to the fact that

medical accidents are easy to cover up, (more easy then car accidents)

and liability of medical staff is difficult to prove, let alone

the liability of a medical equipment manufacturer.

See the discussion on the Therac-25.

 

Gert Gremmen

 

 

 

 

 

 

 

Van: emc-p...@ieee.org [mailto:emc-p...@ieee.org] Namens Conway, Patrick R
(Houston)
Verzonden: Wednesday, June 25, 2008 4:08 PM
Aan: Rudd, Adam; emc-p...@ieee.org
Onderwerp: RE: EMC in the news: RFID & Medical

 

...and if you put four of them in a circle, you can pop corn.  :)

 

 

 

Best Regards, 

Patrick. 
p.con...@hp.com 

 

 



From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Rudd, A

Re: EMC in the news: RFID & Medical

[pat.lawler]

Hi John: 

Unfortunately, the printed report doesn't seem to be available at that
address.  I was hoping to read a computerized translation of the report, as
poor as that might be. 
If anyone can find the report (or a link to it), I'm interested in it.  It
certainly seems to have stirred up interest! 

Pat Lawler
EMC Engineer
SL Power Electronics Corp.

John Woodgate  wrote on 06/26/2008 03:07:11 AM:
> In message ,
> dated Thu, 26 Jun 2008, Gert Gremmen 
> writes:
> 
> >The report was produced by TNO, a Dutch private organization
> >
> >(http://www.tno.nl/content.cfm?&context=markten&content=markt_persberich
> >t&laag1=189&item_id=200806250026&Taal=2) 
> Only available in Dutch.
> >
> > 
> >and some results are available here:
> >http://www.amc.nl/?pid=5266

> No indication of field strengths!
> >
> >Manufacturers name and equipment type included.
> >
> >Please note that the energy levels of RFID are in the milliwatt range,
> >
> >so all problems are to be categorized as immunity deficits.

> But maybe the immunity requirements of the EMC standard aren't violated.
> >
> >It is astonishing that the security of healthy persons (like car
> >drivers)
> >
> >is taken much more seriously (by car manufacturers for example )
> >
> >as the security  of people with bad health like in hospitals.
> >
> >Most medical equipment is tested  at 10 V/meter or less.
> >
> >where critical car parts must  be tested up to 200V/m.

> When cars failed due to high field strengths from broadcast
> transmitters, there was a very public outcry. I didn't hear of any
> outcry about medical equipment problems, presumably because the public
> almost never get to hear of them.

> There was a case in UK a few years ago about faulty oxygen equipment
> (not an electronics problem) causing several deaths, but such cases are
> very rarely reported.
> --

> OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk
> Either we are causing global warming, in which case we may be able to stop
it,
> or natural variation is causing it, and we probably can't stop it. You
choose!
> John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK 
-  This
message is from the IEEE Product Safety Engineering Society emc-pstc
discussion list. Website: http://www.ieee-pses.org/ 

To post a message to the list, send your e-mail to emc-p...@ieee.org 

Instructions: http://listserv.ieee.org/request/user-guide.html 

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For help, send mail to the list administrators: 

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For policy questions, send mail to: 

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All emc-pstc postings are archived and searchable on the web at: 

http://www.ieeecommunities.org/emc-pstc 

[SPAM] RE: EMC in the news: RFID & Medical

[Honkala, Ari (Espoo)]

There’s a possibility, depending the cables and interface types in EUT, that
the 61000-4-6 test did not apply much current to the device.

 

Ari Honkala

SGS Fimko Oy

Finland

 



From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Ken Javor
Sent: 26. kesäkuuta 2008 18:14
To: Untitled
Subject: Re: EMC in the news: RFID & Medical

 

Comment (e) is unrealistic.  Assuming 61000-4-6 was applied, the amount of
power required to directly inject 1, 3 or 10 Volts oc into 150 Ohms is well
above the radiated power from an rf id device. 
Ken Javor

Phone: (256) 650-5261





From: "Conway, Patrick R (Houston)" 
List-Post: emc-pstc@listserv.ieee.org
List-Post: emc-pstc@listserv.ieee.org
List-Post: emc-pstc@listserv.ieee.org
Date: Thu, 26 Jun 2008 14:17:00 +
To: Gert Gremmen , "Rudd, Adam"
, "emc-p...@ieee.org" 
Conversation: EMC in the news: RFID & Medical
Subject: RE: EMC in the news: RFID & Medical

Gert-
You mention one possible reason for the test results is that the EUT's
have immunity deficits.
   I agree, that is one possibility.  

   here are a few other possibilities:   
(BTW- not affiliated in any way with medical devices nor with, all
comments OOO )

 
b)Could it be a systemic testing error?
Was a shield room used?   
Were the ambients controlled and eliminated?
Were the devices connected to a patient simulator?
Did the test engineer have his personal GSM phone "OFF"?  etc. 
(...crazier things have happened.)

 
c)Maybe the EUT are old.
Through outdated design specs perhaps RFID proximity was not a
consideration during their design.
   And yet, in today's hospitals, the two types of devices may be in
close proximity.
   If this is the case then the study has done a great service to the
community by uncovering a problem that was unknown.

 
d)Maybe the EUT are old (not a repeat) 
   Through many years of use perhaps once immune equipment has lost
some of their designed immunity?
   Again- if this is the case this study may have uncovered a
previously unknown problem.


e)Is it possible for an RF ID device to overwhelm the immunity levels of
the EUT?
If a medical device is tested at 10 V/m and an RFID device TXout is in
the mW range- is it possible for a RFID mW transmitter to generate 10 V/m?
Perhaps.
For instance- since an RFID device operating at 125 kHz in not
transmitting in the classic sense, then there may be near-field resonant
effects that are not previously understood in the medical device immunity
requirements?
   

 
   It seems that we, as professionals in this field, have the unique ability
to analyze these reports like no other community can.  I wonder if we will
find the answers to the large number of questions raised by the article.  

 
 
All comments OOO.
Best Regards, 

Patrick. 
p.con...@hp.com 

 



From: Gert Gremmen [mailto:administra...@ce-test.info]
<mailto:administra...@ce-test.info%5d>  
Sent: Thursday, June 26, 2008 2:57 AM
To: Conway, Patrick R (Houston); Rudd, Adam; emc-p...@ieee.org
Subject: RE: EMC in the news: RFID & Medical

The report was produced by TNO, a Dutch private organization
(http://www.tno.nl/content.cfm?&context
markten&content=markt_persbericht&laag1=189&item_id=200806250026&Taal=2
<http://www.tno.nl/content.cfm?&con
ext=markten&content=markt_persberic
t&laag1=189&item_id=200806250026&Taal=2>
<http://www.tno.nl/content.cfm?&context
markten&content=markt_persbericht&laag1=189&item_id=200806250026&Taal=2>  )
 
and some results are available here:
 
http://www.amc.nl/?pid=5266
 
Manufacturers name and equipment type included.
 
Please note that the energy levels of RFID are in the milliwatt range,
so all problems are to be categorized as immunity deficits.
 
 
It is astonishing that the security of healthy persons (like car drivers) 
is taken much more seriously (by car manufacturers for example )
as the security  of people with bad health like in hospitals.
Most medical equipment is tested  at 10 V/meter or less.
where critical car parts must  be tested up to 200V/m.
 
Cars are to be sold at low prices (relatively) , medical equipment
at sky-high costs.  It seems that emc quality is the inverse of the
costs of equipment. Where much attention is given to
reliability and electrical safety of medical equipment,
emc is still  neglected. 
Note that this investigation was made in a Dutch
University Hospital;
On  European soil , where immunity requirements have been 
virtually law since 1996 
 
The lack of EMC care might be related to the fact that
medical accidents are easy to cover up, (more easy then car accidents)
and liability of medic

[SPAM] Re: EMC in the news: RFID & Medical

[Ken Javor]

Comment (e) is unrealistic.  Assuming 61000-4-6 was applied, the amount of
power required to directly inject 1, 3 or 10 Volts oc into 150 Ohms is well
above the radiated power from an rf id device. 
Ken Javor

Phone: (256) 650-5261





From: "Conway, Patrick R (Houston)" 
List-Post: emc-pstc@listserv.ieee.org
List-Post: emc-pstc@listserv.ieee.org
List-Post: emc-pstc@listserv.ieee.org
Date: Thu, 26 Jun 2008 14:17:00 +
To: Gert Gremmen , "Rudd, Adam"
, "emc-p...@ieee.org" 
Conversation: EMC in the news: RFID & Medical
Subject: RE: EMC in the news: RFID & Medical

Gert-
You mention one possible reason for the test results is that the EUT's
have immunity deficits.
   I agree, that is one possibility.  

   here are a few other possibilities:   
(BTW- not affiliated in any way with medical devices nor with, all
comments OOO )

 
b)Could it be a systemic testing error?
Was a shield room used?   
Were the ambients controlled and eliminated?
Were the devices connected to a patient simulator?
Did the test engineer have his personal GSM phone "OFF"?  etc. 
(...crazier things have happened.)

 
c)Maybe the EUT are old.
Through outdated design specs perhaps RFID proximity was not a
consideration during their design.
   And yet, in today's hospitals, the two types of devices may be in
close proximity.
   If this is the case then the study has done a great service to the
community by uncovering a problem that was unknown.

 
d)Maybe the EUT are old (not a repeat) 
   Through many years of use perhaps once immune equipment has lost
some of their designed immunity?
   Again- if this is the case this study may have uncovered a
previously unknown problem.


e)Is it possible for an RF ID device to overwhelm the immunity levels of
the EUT?
If a medical device is tested at 10 V/m and an RFID device TXout is in
the mW range- is it possible for a RFID mW transmitter to generate 10 V/m?
Perhaps.
For instance- since an RFID device operating at 125 kHz in not
transmitting in the classic sense, then there may be near-field resonant
effects that are not previously understood in the medical device immunity
requirements?
   

 
   It seems that we, as professionals in this field, have the unique ability
to analyze these reports like no other community can.  I wonder if we will
find the answers to the large number of questions raised by the article.  

 
 
All comments OOO.
Best Regards, 

Patrick. 
p.con...@hp.com 

 




From: Gert Gremmen [mailto:administra...@ce-test.info] 
Sent: Thursday, June 26, 2008 2:57 AM
To: Conway, Patrick R (Houston); Rudd, Adam; emc-p...@ieee.org
Subject: RE: EMC in the news: RFID & Medical

The report was produced by TNO, a Dutch private organization
(http://www.tno.nl/content.cfm?&context
markten&content=markt_persbericht&laag1=189&item_id=200806250026&Taal=2
<http://www.tno.nl/content.cfm?&con
ext=markten&content=markt_persberic
t&laag1=189&item_id=200806250026&Taal=2>
<http://www.tno.nl/content.cfm?&context
markten&content=markt_persbericht&laag1=189&item_id=200806250026&Taal=2>  )
 
and some results are available here:
 
http://www.amc.nl/?pid=5266
 
Manufacturers name and equipment type included.
 
Please note that the energy levels of RFID are in the milliwatt range,
so all problems are to be categorized as immunity deficits.
 
 
It is astonishing that the security of healthy persons (like car drivers) 
is taken much more seriously (by car manufacturers for example )
as the security  of people with bad health like in hospitals.
Most medical equipment is tested  at 10 V/meter or less.
where critical car parts must  be tested up to 200V/m.
 
Cars are to be sold at low prices (relatively) , medical equipment
at sky-high costs.  It seems that emc quality is the inverse of the
costs of equipment. Where much attention is given to
reliability and electrical safety of medical equipment,
emc is still  neglected. 
Note that this investigation was made in a Dutch
University Hospital;
On  European soil , where immunity requirements have been 
virtually law since 1996 
 
The lack of EMC care might be related to the fact that
medical accidents are easy to cover up, (more easy then car accidents)
and liability of medical staff is difficult to prove, let alone
the liability of a medical equipment manufacturer.
See the discussion on the Therac-25.
 
Gert Gremmen
 
 
 
 
 
 
 

Van: emc-p...@ieee.org [mailto:emc-p...@ieee.org] Namens Conway, Patrick R
(Houston)
Verzonden: Wednesday, June 25, 2008 4:08 PM
Aan: Rudd, Adam; emc-p...@ieee.org
Onderwerp: RE: EMC in the news: RFID & Medical

...and if you put four of them in a circle, you can pop corn.  :)

 

Re: EMC in the news: RFID & Medical

[Ken Javor]

The major difference between medical and automotive equipment is volume.  The
engineering to build in immunity is spread across a huge volume in the
automotive industry; not so for medical equipment, where volumes are much
smaller.  Next, hospitals have a controlled rf environment; automobiles may go
anywhere.  Finally, the automotive solution to 200 V/m is typically not to
operate through, but to gracefully degrade. For instance, ABS defaults to
normal non-electronic braking.  That isn’t possible with medical equipment
performing its sole function. 

Mr. Woodgate correctly points out that an rf source of a few milliwatts can
generate a field on the order of immunity requirements close in, and note that
rf id typically works at frequencies below the 61000-4-3 frequency range. 
This may be a “hole” in the 61000-4-3 requirement: the break between
61000-4-6 and 61000-4-3 is based on coupling to cables dominating coupling to
equipment internal circuitry at low frequencies; this may not always be the
case with plastic enclosures and sensitive low-level measurements.
 
Ken Javor

Phone: (256) 650-5261





From: Gert Gremmen 
List-Post: emc-pstc@listserv.ieee.org
List-Post: emc-pstc@listserv.ieee.org
List-Post: emc-pstc@listserv.ieee.org
Date: Thu, 26 Jun 2008 09:57:07 +0200
To: "Conway, Patrick R (Houston)" , "Rudd, Adam"
, 
Conversation: EMC in the news: RFID & Medical
Subject: RE: EMC in the news: RFID & Medical

The report was produced by TNO, a Dutch private organization
(http://www.tno.nl/content.cfm?&context
markten&content=markt_persbericht&laag1=189&item_id=200806250026&Taal=2
<http://www.tno.nl/content.cfm?&con
ext=markten&content=markt_persberic
t&laag1=189&item_id=200806250026&Taal=2>
<http://www.tno.nl/content.cfm?&context
markten&content=markt_persbericht&laag1=189&item_id=200806250026&Taal=2>  )
 
and some results are available here:
 
http://www.amc.nl/?pid=5266
 
Manufacturers name and equipment type included.
 
Please note that the energy levels of RFID are in the milliwatt range,
so all problems are to be categorized as immunity deficits.
 
 
It is astonishing that the security of healthy persons (like car drivers) 
is taken much more seriously (by car manufacturers for example )
as the security  of people with bad health like in hospitals.
Most medical equipment is tested  at 10 V/meter or less.
where critical car parts must  be tested up to 200V/m.
 
Cars are to be sold at low prices (relatively) , medical equipment
at sky-high costs.  It seems that emc quality is the inverse of the
costs of equipment. Where much attention is given to
reliability and electrical safety of medical equipment,
emc is still  neglected. 
Note that this investigation was made in a Dutch
University Hospital;
On  European soil , where immunity requirements have been 
virtually law since 1996 
 
The lack of EMC care might be related to the fact that
medical accidents are easy to cover up, (more easy then car accidents)
and liability of medical staff is difficult to prove, let alone
the liability of a medical equipment manufacturer.
See the discussion on the Therac-25.
 
Gert Gremmen
 
 
 
 
 
 
 

Van: emc-p...@ieee.org [mailto:emc-p...@ieee.org] Namens Conway, Patrick R
(Houston)
Verzonden: Wednesday, June 25, 2008 4:08 PM
Aan: Rudd, Adam; emc-p...@ieee.org
Onderwerp: RE: EMC in the news: RFID & Medical

...and if you put four of them in a circle, you can pop corn. :)

 

 

Best Regards, 
Patrick. 
p.con...@hp.com 

 
  




From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Rudd, Adam
Sent: Wednesday, June 25, 2008 7:19 AM
To: emc-p...@ieee.org
Subject: EMC in the news: RFID & Medical
“The latest research, conducted at Vrije University in Amsterdam, tested the
effect of holding both "passive" and powered RFIDs close to 41 medical
devices, including ventilators, syringe pumps, dialysis machines and
pacemakers.

A total of 123 tests, three on each machine, were carried out, and 34 produced
an "incident" in which the RFID appeared to have an effect - 24 of which were
deemed either "significant" or "hazardous".

In some tests, RFIDs either switched off or changed the settings on mechanical
ventilators, completely stopped the working of syringe pumps, caused external
pacemakers to malfunction, and halted dialysis machines.

The device did not have to be held right up to the machine to make this happen
- some "hazardous" incidents happened when the RFID was more than 10 inches
away.”

--http://news.bbc.co.uk/2/hi/health/7471008.stm
<http://news.bbc.co.uk/2/hi/health/7471008.stm>
<http://news.bbc.co.uk/2/hi/health/7471008.stm>  

Best Regards,

Adam Rudd

Electrical Engineer (EMC)

NCR Corporation, RHSS

Duluth, GA

(770) 495-2825

- ---

[SPAM] RE: EMC in the news: RFID & Medical

[Conway, Patrick R (Houston)]

Gert-
You mention one possible reason for the test results is that the EUT's
have immunity deficits.
I agree, that is one possibility.  
 
here are a few other possibilities:   
(BTW- not affiliated in any way with medical devices nor with, all
comments OOO )
 
 
b)Could it be a systemic testing error?
Was a shield room used?   
Were the ambients controlled and eliminated?
Were the devices connected to a patient simulator?
Did the test engineer have his personal GSM phone "OFF"?  etc. 
(...crazier things have happened.)
 
 
c)Maybe the EUT are old.
Through outdated design specs perhaps RFID proximity was not a
consideration during their design.
And yet, in today's hospitals, the two types of devices may be in
close proximity.
If this is the case then the study has done a great service to the
community by uncovering a problem that was unknown.
 
 
d)Maybe the EUT are old (not a repeat) 
Through many years of use perhaps once immune equipment has lost
some of their designed immunity?
Again- if this is the case this study may have uncovered a
previously unknown problem.
 

e)Is it possible for an RF ID device to overwhelm the immunity levels of
the EUT?
If a medical device is tested at 10 V/m and an RFID device TXout is in
the mW range- is it possible for a RFID mW transmitter to generate 10 V/m?
Perhaps.
For instance- since an RFID device operating at 125 kHz in not
transmitting in the classic sense, then there may be near-field resonant
effects that are not previously understood in the medical device immunity
requirements?
   
 
 
It seems that we, as professionals in this field, have the unique ability
to analyze these reports like no other community can.  I wonder if we will
find the answers to the large number of questions raised by the article.  
 
 
 
All comments OOO.

Best Regards, 

Patrick. 
p.con...@hp.com 

 



From: Gert Gremmen [mailto:administra...@ce-test.info] 
Sent: Thursday, June 26, 2008 2:57 AM
To: Conway, Patrick R (Houston); Rudd, Adam; emc-p...@ieee.org
Subject: RE: EMC in the news: RFID & Medical



The report was produced by TNO, a Dutch private organization

(http://www.tno.nl/content.cfm?&context
markten&content=markt_persbericht&laag1=189&item_id=200806250026&Taal=2)

 

and some results are available here:

 

http://www.amc.nl/?pid=5266

 

Manufacturers name and equipment type included.

 

Please note that the energy levels of RFID are in the milliwatt range,

so all problems are to be categorized as immunity deficits.

 

 

It is astonishing that the security of healthy persons (like car drivers) 

is taken much more seriously (by car manufacturers for example )

as the security  of people with bad health like in hospitals.

Most medical equipment is tested  at 10 V/meter or less.

where critical car parts must  be tested up to 200V/m.

 

Cars are to be sold at low prices (relatively) , medical equipment

at sky-high costs.  It seems that emc quality is the inverse of the

costs of equipment. Where much attention is given to

reliability and electrical safety of medical equipment,

emc is still  neglected. 

Note that this investigation was made in a Dutch

University Hospital;

On  European soil , where immunity requirements have been 

virtually law since 1996 

 

The lack of EMC care might be related to the fact that

medical accidents are easy to cover up, (more easy then car accidents)

and liability of medical staff is difficult to prove, let alone

the liability of a medical equipment manufacturer.

See the discussion on the Therac-25.

 

Gert Gremmen

 

 

 

 

 

 

 

Van: emc-p...@ieee.org [mailto:emc-p...@ieee.org] Namens Conway, Patrick R
(Houston)
Verzonden: Wednesday, June 25, 2008 4:08 PM
Aan: Rudd, Adam; emc-p...@ieee.org
Onderwerp: RE: EMC in the news: RFID & Medical

 

...and if you put four of them in a circle, you can pop corn.  :)

 

 

 

Best Regards, 

Patrick. 
p.con...@hp.com 

 

 



From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Rudd, Adam
Sent: Wednesday, June 25, 2008 7:19 AM
To: emc-p...@ieee.org
Subject: EMC in the news: RFID & Medical

“The latest research, conducted at Vrije University in Amsterdam, tested the
effect of holding both "passive" and powered RFIDs close to 41 medical
devices, including ventilators, syringe pumps, dialysis machines and
pacemakers.

A total of 123 tests, three on each machine, were carried out, and 34 produced
an "incident" in which the RFID appeared to have an effect - 24 of which were
deemed either "significant" or "hazardous".

In some tests, RFIDs either switched off or changed the settings on mechanical
ventilators, completely stopped 

Re: EMC in the news: RFID & Medical

[John Woodgate]

In message , 
dated Thu, 26 Jun 2008, Gert Gremmen  
writes:


>The report was produced by TNO, a Dutch private organization
>
>(http://www.tno.nl/content.cfm?&context=markten&content=markt_persberich
>t&laag1=189&item_id=200806250026&Taal=2)

Only available in Dutch.
>
> 
>
>and some results are available here:
>
> 
>
>http://www.amc.nl/?pid=5266

No indication of field strengths!
>
> 
>
>Manufacturers name and equipment type included.
>
> 
>
>Please note that the energy levels of RFID are in the milliwatt range,
>
>so all problems are to be categorized as immunity deficits.


But maybe the immunity requirements of the EMC standard aren't violated.
>
> 
>
> 
>
>It is astonishing that the security of healthy persons (like car 
>drivers)
>
>is taken much more seriously (by car manufacturers for example )
>
>as the security  of people with bad health like in hospitals.
>
>Most medical equipment is tested  at 10 V/meter or less.
>
>where critical car parts must  be tested up to 200V/m.

When cars failed due to high field strengths from broadcast 
transmitters, there was a very public outcry. I didn't hear of any 
outcry about medical equipment problems, presumably because the public 
almost never get to hear of them.

There was a case in UK a few years ago about faulty oxygen equipment 
(not an electronics problem) causing several deaths, but such cases are 
very rarely reported.
-- 
OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk
Either we are causing global warming, in which case we may be able to stop it,
or natural variation is causing it, and we probably can't stop it. You choose!
John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

-

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RE: EMC in the news: RFID & Medical

[Gert Gremmen]

The report was produced by TNO, a Dutch private organization

(http://www.tno.nl/content.cfm?&context
markten&content=markt_persbericht&laag1=189&item_id=200806250026&Taal=2)

 

and some results are available here:

 

http://www.amc.nl/?pid=5266

 

Manufacturers name and equipment type included.

 

Please note that the energy levels of RFID are in the milliwatt range,

so all problems are to be categorized as immunity deficits.

 

 

It is astonishing that the security of healthy persons (like car drivers) 

is taken much more seriously (by car manufacturers for example )

as the security  of people with bad health like in hospitals.

Most medical equipment is tested  at 10 V/meter or less.

where critical car parts must  be tested up to 200V/m.

 

Cars are to be sold at low prices (relatively) , medical equipment

at sky-high costs.  It seems that emc quality is the inverse of the

costs of equipment. Where much attention is given to

reliability and electrical safety of medical equipment,

emc is still  neglected. 

Note that this investigation was made in a Dutch

University Hospital;

On  European soil , where immunity requirements have been 

virtually law since 1996 

 

The lack of EMC care might be related to the fact that

medical accidents are easy to cover up, (more easy then car accidents)

and liability of medical staff is difficult to prove, let alone

the liability of a medical equipment manufacturer.

See the discussion on the Therac-25.

 

Gert Gremmen

 

 

 

 

 

 

 

Van: emc-p...@ieee.org [mailto:emc-p...@ieee.org] Namens Conway, Patrick R
(Houston)
Verzonden: Wednesday, June 25, 2008 4:08 PM
Aan: Rudd, Adam; emc-p...@ieee.org
Onderwerp: RE: EMC in the news: RFID & Medical

 

...and if you put four of them in a circle, you can pop corn.  :)

 

 

 

Best Regards, 

Patrick. 
p.con...@hp.com 

 

 



From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Rudd, Adam
Sent: Wednesday, June 25, 2008 7:19 AM
To: emc-p...@ieee.org
Subject: EMC in the news: RFID & Medical

“The latest research, conducted at Vrije University in Amsterdam, tested the
effect of holding both "passive" and powered RFIDs close to 41 medical
devices, including ventilators, syringe pumps, dialysis machines and
pacemakers.

A total of 123 tests, three on each machine, were carried out, and 34 produced
an "incident" in which the RFID appeared to have an effect - 24 of which were
deemed either "significant" or "hazardous".

In some tests, RFIDs either switched off or changed the settings on mechanical
ventilators, completely stopped the working of syringe pumps, caused external
pacemakers to malfunction, and halted dialysis machines.

The device did not have to be held right up to the machine to make this happen
- some "hazardous" incidents happened when the RFID was more than 10 inches
away.”

--http://news.bbc.co.uk/2/hi/health/7471008.stm
<http://news.bbc.co.uk/2/hi/health/7471008.stm> 

Best Regards,

Adam Rudd

Electrical Engineer (EMC)

NCR Corporation, RHSS

Duluth, GA

(770) 495-2825

-  This
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Fo

RE: EMC in the news: RFID & Medical

[Conway, Patrick R (Houston)]

...and if you put four of them in a circle, you can pop corn.  :)
 
 
 
Best Regards, 

Patrick. 
p.con...@hp.com 

 



From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Rudd, Adam
Sent: Wednesday, June 25, 2008 7:19 AM
To: emc-p...@ieee.org
Subject: EMC in the news: RFID & Medical



“The latest research, conducted at Vrije University in Amsterdam, tested the
effect of holding both "passive" and powered RFIDs close to 41 medical
devices, including ventilators, syringe pumps, dialysis machines and
pacemakers.

A total of 123 tests, three on each machine, were carried out, and 34 produced
an "incident" in which the RFID appeared to have an effect - 24 of which were
deemed either "significant" or "hazardous".

In some tests, RFIDs either switched off or changed the settings on mechanical
ventilators, completely stopped the working of syringe pumps, caused external
pacemakers to malfunction, and halted dialysis machines.

The device did not have to be held right up to the machine to make this happen
- some "hazardous" incidents happened when the RFID was more than 10 inches
away.”

--http://news.bbc.co.uk/2/hi/health/7471008.stm
 

Best Regards,

Adam Rudd

Electrical Engineer (EMC)

NCR Corporation, RHSS

Duluth, GA

(770) 495-2825

-  This
message is from the IEEE Product Safety Engineering Society emc-pstc
discussion list. Website: http://www.ieee-pses.org/ 

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All emc-pstc postings are archived and searchable on the web at: 

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-  This
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RE: EMC in the news: RFID & Medical

[Umbdenstock, Don]

125 kHz and 868 MHz.  Interestingly, one would think filtering at the higher
frequencies would be easier to implement, but indications are that the higher
frequency had more hits.

It doesn’t indicate the degree of compliance with the medical devices
immunity requirements.

Don 
561 912  6440 



From: emc-p...@ieee.org [mailto:emc-p...@ieee.org] On Behalf Of Andrew McCallum
Sent: Wednesday, June 25, 2008 8:39 AM
To: EMC-PSTC@LISTSERV.IEEE.ORG
Subject: EMC in the news: RFID & Medical

 

Be interesting to see exactly what they tested. 

Was the medical equipment built to the current Medical Equipment Directive or
not.

What frequencies did the RFID equipment work on.

Was it the reader or the tag that was 10cm away from the affected equipment.

Need to see the full report

 

Regards

 

Andy

 

 




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