Thursday, September 06, 2007
The truth about 'no cell zones'
Are you one of those people who ignore the signs in hospitals telling you to turn off your cell phone? You're not alone. As I walk through my hospital, I see lots of people - patients and doctors alike talking on their phones, seemingly oblivious to any dangers they might be causing. In fact, if you asked most of these people, they would probably say their personal phone is unlikely to cause any sort of problem with patient care. Turns out they are wrong and the consequences could be serious.

A new Dutch study, published in the journal Critical Care, concluded that we should keep all cell phones, Blackberries and anything that transmits data back and forth off, and at a minimum of three feet away from any medical equipment. That's right. It doesn't matter if you are talking on it or not, simply having it on could cause a problem. The culprit is electromagnetic interference which, when simulated in the study, caused some pretty bizarre and life threatening problems.

The researchers found interference with a variety of machines, including one, a mechanical ventilator or breathing machine, which switched off and on. In other situations, a pacemaker didn't detect an EKG signal and an infusion pump stopped. Of course, in the study, no patients were being treated, but the implications were clear.

The worst offenders seem to be devices that are GPRS based or use WiFi and get on the internet. Previous studies, such as one from the Mayo Clinic, found no interference with normal phones and normal usage. As things stand right now, there are no national guidelines on cell phone usage in hospitals. My hospital, for example, allows no usage, whereas other places may be more liberal. A good rule of thumb, though, is to probably turn off your phone entirely when in intensive care units, emergency rooms and near operating room suites.

I think most people will hear this story and be more diligent about obeying the signs in hospitals. I am curious, though, about a couple of other related issues. What do you think about the use of cell phones on airplanes? Real problem or hype? And, also do any of you worry about a relationship between cell phone usage and brain tumors?
While I understand the restrictions for cell phones, as an engineer it frightens me that a small, low-powered device could interrupt the functions of a mechanical ventilator. I'd be far more worried about the design of that machine. Given the almost omnipresence of cell phones and similar devices, we will likely never remove the external electromagnetic fields that surround us. Medical equipment designers should be taking all that into account.

As for cell phones on airplanes, I'm dead set against them. One has only to watch and listen to the activity when a plane lands to realize that there is little conversation of any consequence that occurs. I doubt the airborne versions would be any more sustantive, and they would certainly be annoying. I have enough stress when traveling without listening to a loud, one-sided conversation somewher around me.

As for brain cancer effects, I thought we had laid that to rest - the early studies were shown to be flawed, and subsequent ones could find no correlation between phone use and brain tumors.
Dr. Gupta:
Because of the instant gratification culture we live in, the cell phone, blackberries, etc. have become the instrument for our information addiction. Only signs reminding hospital visitors to shut off their electronic devices will give the "users" a hint to shut them off. Without signs or reminders, users will be oblivious to the danger it could cause to others.

Do the families of individuals on lifesaving devices in hospitals really want to take the chance of an interruption due to a cell phone? Unlikely.

Airplanes? I remember on 911, the hijacked airplines' passengers were able to communicate with their cell phones while in the air. Is the concern about electronic disruption or security?

Brain tumors and cell phones? Have there been substantial studies on this? If this is correct, I don't think we will see conclusive evidence until many years from now. In the meantime, Americans will not be willing to give up their cell phones for anything.
The UK's National Health Service has just released a guidance document regarding the use of cellphones in hospitals. The guidance also refers to the legal ramifications of cellphones with video or camera capabilities.

From last week's CDC Public Health Law News (

The U.K.'s National Health Service (NHS) has reviewed previously issued guidance banning mobile phones in hospitals, and now offers a legal framework and an evidence base for the revision of hospital policies across the country. According to the NHS guidance document, "Using mobile phones in NHS hospitals," a ban on mobile phones in NHS hospitals was "based on the risks associated with the interference of medical equipment, which is well documented." But "[m]isinformation regarding mobile wireless systems, electromagnetic interference and management procedures has led to a broad range of inconsistent policies among healthcare organizations." A broader concern with the use of cell phones, especially those with cameras and video recorders, has to do with patient privacy and confidentiality, and nuisance.

The guidance reviews the legal framework concerning the protection of patient privacy and dignity under the Human Rights Act 1998, patient confidentiality under the Data Protection Act 1998, protection of children under the Children Act 2004, and nuisance (currently in consultation). The guidance concludes,

"Trusts should consider a range of risks and issues when preparing their policy regarding where mobile phones should and should not be allowed to be switched on and used in hospitals.

The issue is not simply one of communication between patients, staff and visitors, but more significantly the potential for the camera and video facility to be used inappropriately, and potentially illegally."

To read the text of the guidance, "Using mobile phones in NHS hospitals," visit
In my hospital, most people are fairly courteous about cell usage in patient areas, which is both pleasing and surprising. As a user of public transit, I've lost count of how many times I've been forced to listen to someone discuss their venereal disease, possible pregnancy, lover's failings, contract details, work schedules, etc.

I hope the day NEVER comes when cells are allowed to be used in-flight. I can easily see fights breaking out.

As for tumors - I thought there've been studies that refute this rumor? Studies NOT paid for by the cell industry, at that! :D
I want to second the comment that it's disturbing that a cell phone would cause interference with the function of any critical equipment. The equipment is the problem, not the cell phone. Modern equipment with solid state switching power supplies can transmit a broad spectrum of electromagnetic noise, both wirelessly and back through a building's electrical system. Most of that noise would be far more powerful than a cell phone transmission. Equipment must be designed to be immune to electromagnetic interference. It's unrealistic to think cell phones are even the most threatening source of dangerous electromagnetic interference in a hospital environment.
I can't bear to think of sitting on a 6 hour cross country flight while listening to one side of a dozen or so conversations. It will make airline travel unbearable in my opinion.
Unfortunately, I feel CNN's decision to hype the results of a single study undermine the vast number of other pieces of data suggesting that most cellphones have no significant effect on most pieces of healthcare equipment. Many top hospitals, those rated among the best in quality of care, have been providing cellphones to medical staff for use inside the hospital for years now. My own wife, an anesthesiologist at a prestigious pediatric institution, told me there have been no documented instances of cellphones (which are carried by most physicians in the operating room) affecting any of the critical care medical equipment during the four years that cellphones have been permitted in the facility. While there certainly may be the odd interaction between one particular phone with one particular device, this is certainly no justification for banning an entire platform of technologies, especially ones that enable so greatly the real-time, life-saving communication among healthcare workers. More research may be needed, but in the meantime, I'll take the risk associated with having cellphones in the hospital, as it's much less than the risk associated with slowing down physicians and nurses by making them rely solely on pagers and wallphones.
Dr. Gupta,

Carl DeFranco has a very valid point, as I have been an Electronic Hardware Specialist for more than 20 years, the issue witht he interference with the medical equipment is a lack of internal shielding on vital components. If these devices are so easily susceptable to the low EMF output of handheld devices, a cheap, one dollar piece of shielding could save serious lives regardless. An example is an emitter in a microwave in the break room burning out, can put out an EMF burst that could realistically encompass 300 square feet or more.

Until then, yes, it would be advisable to turn off handheld electronics. But then, that laptop in the ER that the nurse inputs data on as she interviews patience also has a lithium ion battery, and if that pops due to a flaw or defect, can be just as deadly. So the obvious answer would be simple. Shield the life saving devices properly.
Dear Dr. Sanjay...

I'm deeply grateful for your warning about using cell phone.

I felt guilty that I used my
cell phone for many times despite
your warning message which asked
refraining from cell phone using in the hospital. --;;

There are a few theories that
cellphones caused the brain tumors.
But in my opinion, the brain tumors
is not only caused by cell phones
but by also different factors
I think.

It will not be able to imagine that
all people's daily lives without
cell phone.... :(

Thanks again. Take care :-)
I agree that everyone should turn off cells, BBs, etc, while in sensitive hospital areas --- and that engineers need to build medical devices that are untouched by such interference.

As for cells on planes: absolutely not! I travel a great deal, and I don't even like cell phone conversations in gate waiting areas. Those conversations are often loud, making us all participants, as opposed to the quiet conversations between two waiting passengers. I think that --- like smoking --- cell phones should be used in designated areas. Let them all share each other's conversations.
Yes, of course, as a computer scientist I'm worried about not only the potential that cell phones have for causing body-cell damage (including brain cells) but also the same kinds of problems with now-ubiquitous wireless computer systems. I am particularly concerned about the effects of these devices on young children. We need good, credible long-term studies.
I am also an engineer and agree with one of the others who commented. I would be most concerned with the life support machines. They are supposed to be able to take a lot more interference than the small amount radiated by cell phones. That aside, since hospital equipment isn't up to the task, I would agree that a safe distance is in order as suggested. An entire ban is not really necessary.

As for airplanes, I also agree. Keep them off -- not because of any danger but because of the annoyance.

An yes, there have been many studies going on for years about the effects of cell phones on human tissue. It's more dangerous to sleep with an electric blanket.
Regarding the final point about cell phone usage and brain tumors, what I find amusing on this point is that a lot of people know about this issue and I know some people who consciously limit their phone use because of it, but nobody I know thinks about the issue as to a Blackberry. Many Blackberry users clip the things to their belts. Now, it seems to me that a cell phone transmits when you're using it, whereas a Blackberry sends and receives constantly, so won't carrying a Blackberry on your belt cause damage somewhere else? (There's a reason the hospital puts that lead sheet over you when they take x-rays.)

To address the practical point, I'm sure almost everyone has heard the interference caused on telephone calls when someone on the phone keeps a Blackberry next to his phone. A lot of people don't seem to realize what causes the problem, though. It stands to reason that if the devices interfere with standard lane-line phones, they can interfere with other things as well (hospital equipment, airport equipment, etc.). I know mine interfered with wireless stereo speakers one day.
As a licensed Amateur radio operator, I know that RFI (radio frequency interference) can even be measured from many non-transmitting devices. Many electronic devices/appliances have circuitry that emits RFI, and do so constantly. These emissions might not be measureable more than a few feet away, but various harmonics can occur, and get into the most sophisticated of electronic apparatus. No cell phones on when near equipment designed to save lives!
As a communictions engineer, I too, am concerned about the design of medical equipment that doesn't protect against electromagnetic interference. Wireless devices are not the only sources of interference. But, that being said, hospitals and other locations (doctors offices) need to remind and insist that wireless devices be turned off. All such devices attempt to communicate with their respective base stations at all times regardless if they are being used or not.

Airplanes: I'm against them, but not because of interference issues which I believe is airline hype. I've never seen or heard of a study proving that they interferred with flight controls.

Brain Tumors: Total hype, or maybe not. That could be why people with cell phones seem to do so many dumb things, like driving and talking. Hmmmm Food for thought. "My cell phone made me do it, officer."
Is it really necessary to use cell phones on planes and in cars, especially when there is the real possibility of potential danger? How about a modicum of quietness for those who cannot bear the self-important, insufferable boors who subject all of us to their cell phone stupidities?

Cell phone addicts are unconscious, disrespectful, discourteous and obnoxious. Public transportation and areas; doctors' offices; theaters; restaurants; checkout lines; just about everywhere. In their own dream world walking like zombies in the street, or "driving" their cars. Their business, everyone's business. Unable to bear silence or be by, or with, themselves for a moment. Totally oblivious to---and inconsiderate of---their neighbors.

Cell phones will be as ubiquitous in airplanes as they are in places where we are all held captive. These (ab)users ought to be relegated to their own soundproof cabin, compelled to suffer one another's inanities. For the entire flight.

I, and hopefully those who share these feelings, will give our business to the airlines that have the sense to ban them.

Emanuel Molho
According to the team at MythBusters, a cell phone is thousands and thousands of times too weak to disrupt any instrument in an airplane. I personally wouldn't use my phone anyway, because I have no interest in the being the cause of a freak disruption and kill myself and everyone else on the plane.

Also, I haven't heard much about brain tumors since the earlier years of cell phones, so I am going to assume (uh oh) that it was all a bunch of speculation. Besides, I don't use my cell phone that much (for talking) anyway. If I get a tumor in my hands from text messaging, I'll be sure to alert the press.
I'm not sure why Sharon D from above is limiting her comments to Americans when we are the least wired of the first (and some second) world nations...

I like the idea of speical "talk" zones on planes where 4-8 seats are set aside for people to jibber jabber on without annoying the remaining 200 of us on the flight.

So far as dangers of having them turned on....seriously? If there was a credible threat that an itty bitty cell phone could bring down a 747 or even a 737...yikes, I'll go Amtrak from now on.
Nonsense. This is all about control. Hospitals, airlines, and other institutions simply want their customers to be under as much control as they possibly can. They own the spaces their customers are in, and want to control, and charge them for, access to the outside world. I am a pilot, and I have also been in the electronics business for over 40 years and I will tell you that, with the exception of the "Three Feet" rule, there is no measurable electronic interference from cell phones, WiFi devices, MP3 players and other such devices, period. Medical and communication devices have a far greater likelihood of interfering with -each other- than a cell phone has of causing danger. Just plain hooey.

Nick Nikon
Austin, Texas
Last week's CDC Public Health Law News ( discusses how the UK is dealing with this. The National Health Service has just released a guidance document detailing some of the legal ramifications of cell phones in hosptials:

The U.K.’s National Health Service (NHS) has reviewed previously issued guidance banning mobile phones in hospitals, and now offers a legal framework and an evidence base for the revision of hospital policies across the country. According to the NHS guidance document, “Using mobile phones in NHS hospitals,” a ban on mobile phones in NHS hospitals was “based on the risks associated with the interference of medical equipment, which is well documented.” But “[m]isinformation regarding mobile wireless systems, electromagnetic interference and management procedures has led to a broad range of inconsistent policies among healthcare organizations.” A broader concern with the use of cell phones, especially those with cameras and video recorders, has to do with patient privacy and confidentiality, and nuisance.

The guidance reviews the legal framework concerning the protection of patient privacy and dignity under the Human Rights Act 1998, patient confidentiality under the Data Protection Act 1998, protection of children under the Children Act 2004, and nuisance (currently in consultation). The guidance concludes,

"Trusts should consider a range of risks and issues when preparing their policy regarding where mobile phones should and should not be allowed to be switched on and used in hospitals.

The issue is not simply one of communication between patients, staff and visitors, but more significantly the potential for the camera and video facility to be used inappropriately, and potentially illegally."

To read the text of the guidance, “Using mobile phones in NHS hospitals,” visit

Rachel, Atlanta
No one really knows the potential effects of EMF on living things and we probably will not know for some time. Our continued exposure keeps growing and growing. Could there be a correlation between increased EMF exposure and the increase in autism in children?

This is the largest human experiment in the history of mankind.
Cell phones anywhere are annoying. On the plane in the hospital at the grocery store check out. If cell phones do cause brain tumors its because people don't give their brains a rest from all the daily stuff that goes on. I personally gave mine up in protest years ago. I think people are losing their social skills because they no longer interact with anyone but that person on the cell phone. To heck with the person behind them or in the ER.
Cell phones on commuter trains are bad enough (and that's only for 30-45 minutes) - I can't imagine the torture of hearing cell phone conversations and annoying ring-tones on a 3-6 hour flight.

I hope that day never comes.
I have to disagree with Dr. Gupta. I work for a company that makes a large majority of those instruments used in hospitals (patient monitors, defibrillators, etc.) and we go to great lengths to prove to the FDA and the FCC that our signals are secure and cannot be interferred with by devices that are also approved by the FCC. If that study is true, why does the FDA insist that we go to all these lengths to ensure such interference doesn't exist?
My father-in-law recently suffered a heart attack and was in the CCU/ICU. He was on a ventilator and several monitors. Signs were up for cell phones to be turned off, but when I asked, I was told they dated to the older analog phones and higher powered bag phones and that the digital cell phones of today were fine if kept more than three feet from medical equipment. There were wireless devices in use by the staff, access point aerials stuck through ceiling tiles in the hallway, and from the waiting room my laptop could see five networks, two unsecured guest access networks, and three secured. The SSID on the secured ones indicated they were for handheld devices, PC access, and medical devices themselves. Adding in the VHF radios used by staff and security, and the cell site close by, and the CCU/ICU is bathed in RF energy. There is no way modern medical equipment is adversly affected by reasonable use of cell phones.
Unfortunately the posting and some of the responses miss some key points:

1. All equipment is susceptible to electromagnetic interference (EMI) from a variety of sources (including cell phones but also some surgical equipment, for example) to one degree or another. The equipment that is most susceptible is older gear with less shielding, which should be phased out because of its vulnerability to EMI from all sources. When our hospital tested the gear we use only two older items (one IV pump and one ventilator) showed interference at > 1 ft, and both of those have been replaced.
2. Cell phones linked to internal networks (such as hospital-based cell systems) transmit at much lower powers than those accessing external antennas, and so are even less likely to cause EMI.
3. The (largely theoretical) problems associated with cell phones in hospitals must be balanced against the well-documented and sometimes fatal effects of poor communication within hospitals. When the right people cannot get to the right patient with the right equipment at the right time, patients sometimes die. To my knowledge there has never been a reported case of patient injury due to EMI, but there is no shortage of reports of patient death or injury due to poor communication.
I read online what was reported to be this Dutch study regarding cell phones and medical equipment. In the article I read it said that the cell phones in this study were 3 cm from the equipment. Who uses their cell phone within 3 cm of the equipment??? Your head and face would almost be touching the equipment at 3 cm!!! What kind of study is this? It certainly doesn't seem realistic or practical to me. Unless the 3 cm was a typo, I find this study to be another waste of money with highly questionable conclusions. And, if the cell phones cause such danger - why have hospitals not banned them from even being brought into the hospital? Why do they allow their own doctors to use them openly in halls and rooms? None of this makes any sense to me.
As a frequent flyer I find it disturbing just to be "force fed" some passenger's conversations. The cabin environment seems to increase volume any way. As to cell phone usage, it's terrible in theaters, restaurants and other public places. Three to four hours of this forced eavesdropping is totally unacceptable, uncomfortable and thoughtless by the sender.
The questions in your article almost invite the posting of rumors and urban myths. The nonsense that goes around on cell phones and other RF devices is astonishing. Fortunately some engineers and others with experience took the time to respond.

The study you cited used a signal generator at two watts output rather than a cell phone which typically operates at levels one third of that or less. The three-foot rule isn't an unreasonable safety margin, but it isn't one based on a real, identified threat. It will do until equipment manufacturers get their act together and build in shielding (very cheap) to make their equipment interference-proof in a world where RF devices will continue to proliferate.
There was recently an episode on the Discovery Channel about this- on Mythbusters- and they proved it false. Cell phones don't affect airplanes.
Hi Dr. Gupta,

Recently on mythbusters they tested cell phone interferance on avonics. As it turns out, some cell phones do interfear with avonics. Although, due to redundant systems on most commericial aircarft, the risk to the aircraft is low. Keep up the good work!
I work as an RN in a hospital which has provided all the staff with wireless communication devices. I have not found it to cause any problem with the equipment we use, but I have found that doctors will be at a patient bedside, receive a cell phone call, and leave the patient laying there, listening to the doctor's call. I have also experienced talking to doctors about a patient, and being interrupted by a cell phone call that the doctor will answer. This is more lack of manners than anything else, but it is bothersome.
I also worry about carrying these wireless devices near my breasts( we are to wear them clipped to our scrub tops) for 12 hours at a stretch.
I am interested in learning if there is any data out there, other than that provided by the product vendor.
As a woman whose husband has been in a Cardiothoracic Intensive Care Unit for the past six weeks, it terrifies me to think that such a common thing as a cell phone could cause any of his medical equipment to malfunction. I myself have my cell phone with me at all times, but I will definitely make sure that it is turned off whenever I am in the hospital. Please, if you enter a hospital, and especially an intensive care unit, turn off your cell phone. Such a simple act could save a life.
I am not too concerned about contemporary cells phones. But, the police shouldermounted, communication units I would guess are FM and probably are 3+ watts. They may present a greater risk, especially if the bearer has a pacemaker. i guess one could check EMS services to see if communications ever fouled up mibile equipment

Dave Tallahassee
I also am an engineer and have dealt with problems aboard helicopters and aircraft due to interference. All equipment is shielded and RFI proof to a great 200 milliwatt telephone is likely to interfere with medical equipment. Inside a hospital, there is a GREAT deal more ambient interference radiated by MRI, X-RAY, radiation treatment devices and, God knows, the myriad of TV sets that radiate in every room in the hospital than would ever be possible by a cellphone...instrumentation HAS to be designed to function in that environment. I would never believe a cellphone would ever cause interference except in the case of EXTREMELY low level signal measuring equipment.
Typical and predictive study results made by people who are by culture trying to be in control.

A cell phone transmits at 0.6watts. If, as other commenter's have stated, this highly sophisticated machinery is choking, how does it work with other medical equipment next to it. The problem is an engineering issue NOT the cell phones!

I for one never believe very little that comes from the medical community - and find most doctors to be self-serving, egomaniacs.

As far as phones on planes - again, cell phones don't interrupt the navigation equipment. It's just the airlines want their money for cell phones or feel people are listening to their inane and ridicules rants on "if we crash" - "if we crash" odds are is that I'm dead --- so I might as well talk on my phone, because I can be reading my book or talking to my seat mate and miss the "customer service agents" instructions...
I have to agree with some of the other respondents - medical equipment should be adequately shielded. Your WiFi comment in particular is good evidence of this - hospitals are chock full of WiFi equipment, doctors like yourself carry WiFi tablet PCs on their rounds. "regular" cellular technology uses different frequencies from WiFi, GPRS, UMTS, and 3G, but those frequency bands are well defined, and cellular telephony has been around long enough that medical equipment manufacturers have had more than enough time to test, and take care of the shielding. What you say applies to all transmitters, including those used by wireless patient monitors, the two way radios used by security and maintenance staff, cordless telephones, etc. You will hopefully agree with me that turning off all transmitters in a hospital would not be feasible, and you can take it from me as a rearch engineer that any such issues are not related to cellphones as such. Radio transmission has been a fact of life in hospitals for some 20 years, and most transmitters used actually broadcast more power than do cellphones.

It should be understood, when reading Dutch and generally European research on these matters, that the maximum permissible output of a handheld GSM device in most locales abroad is 1.5 watts. Here in the US, the FCC curtailed that to 750 milliwatts, half that amount of power, so the Dutch may well find issues with their transmitters that would not occur here.
Aircraft avionics, computers and the such that are judged to be safety critical, have to meet and be PROVEN to meet, strict conducted and radiated emissions requirements. As a result interference from cell phone signals is not a problem on aircraft. However medical equipment is not held to the same strict standards. Though electro mechanical interference (EMI) requirements may be imposed upon the equipment, independent certification of compliance is nor widely required. As a result, some medical equipment is not only suceptable to interference from cell phone frequencies, but the equipment is also suceptable to interference or interfering with other medical equipment.
I certainly understand that cell phone usage in hospitals is the sort of topic that is "newsworthy" in the sense that it is intellectually accessible to the average person and concerns a piece of technology that few of us would be without. I think though that focusing discussion on this topic is an example of how the media fails us.

Every year in the US, something like 100,000 people die from preventable medical errors (which wouldn't include theoretical cell-induced malfunctions) and some even larger number of patients die because they don't get all the care they need. In fact, studies show that Americans on average only get 55% of the evidence-based care they need. 89,000 patients die of nosocomial infections, the biggest preventer of which is proper handhygiene (which physicians only obey about 80% of the time). Dr. Ignaz Semmelweis showed that handwashing was important in preventing death 160 years ago (1847 in Austria) yet we still can't figure out how to do that in "modern" medicine.

So, we have hundereds, maybe a thousand patients dying every day in our hospitals that don't have to. And CNN is going to point the discussion toward a theoretical risk from cell phones? Dr. Gupta, that demonstrates neither sound logic or good judgement.

It amazes me that this many people die every year and it isn't the lead story on every one of your newscasts and the headline of each newspaper everyday. Somehow, we allow this tragedy to unfold under our radar. As a physician who spends much of my effort on patient safety and quality improvement, I know firsthand that the solutions to these pervasive and cultural problems of quality and safety in healthcare are not easily remedied. Dr. Gupta, as a recognised commentator on medical topics, I would encourage you to consider focusing on real patient safety issues. Why not take each of the evidence-based practices that we are only incompletely following and use your position to influence the public on what needs to be done?

This of course would take considerably much more effort, be harder to convince your executive producers the value of, and be decidedly less sexy than the "phantom cell phone risk". It would however potentially be of value to your viewers and might advance the discussion and improve the care of patients in our country. Remember that silence is complicity and your and my duty as physicians is to "first do no harm".
I'll have to pull the article. But other studies have not shown significant interference.
The other problem is physicians (I am one) are routinely using their cell phones including in CCU, ICU! It's very hard to enforce the no cell phone rule for the public when doctors are openly chatting.
I believe technically we still have the no cell phone rule in my hospital but as I've said, it's not being followed by anyone.
As a retired airline pilot, I, too was suspicious of the cell-phone restriction policy of the '90s when I was actively flying. However, I did observe a ramp agent walking around another airplane next to mine while parked one day, keying the mike on his "walkie-talkie" and amusing himself with the ability to open and close that airplanes outflow valve (which controls cabin pressure). This, of course was not dangerous being on the ground, but certainly he would have disastrous consequences should he have done this when airborne. However, the frequency and power of his device was not the same as a cell phone, and never allowed onboard. I have also experienced navigation deviations caused by the malfunction of my own plane's HF radio. (I turned it off and reported the aberrancy for subsequent repair). Herein lies the problem: A properly designed device, when used in accordance with design parameters, and is functioning properly, ostensibly no danger is posed... only under random situations of malfunctioning equipment is there a danger of interference. To take a conservative position and disallow the use of all unnecessary devices is prudent where a danger to the safety of lives is possible, no matter how remote. If a telephone conversation can simply be delayed until out of the range of critical equipment, why not?
I agree cell phones should be turned off in hospitals. I live in Winnipeg, Manitoba, Canada and all our hospitals here have signs posted in numerous places reminding people to turn them off. As for the brain tumors... I had one removed in 2002.. I don't own a cell phone.
I do believe the thing about cellphones is mainly to keep people more quiet on a flight than if they were gabbing on a cellphone. Also, in my opinion, they are for general safety so people pay attention to the flight attendants when necessary.
Regardless of whether a cellular phone can interfere with these machines are not, I am not who wants to risk anything. Sometimes, it would just be better to shut off your phones anyway because too many people many people in that hospital are stressed and can get too eassily aggitated, they are patients trying to rest and relax and would rather not hear the constant ringing and one-sded chatting, or doctors who seriously need to concentrate and don't need that one distraction that could cause them to make a mistake in reading and analyzing information, whether in the process of diagnostics or just basic blood readings.
Our own testing on a variety of biomedical devices found no issues. We had the cell phones next to the equipment, turned on with the covers off, no issues. We tested over 100 unique pieces of equipment. Of course this can't be the final word and we have agreed to keep a three foot rule, from all biomed gear in use and no cell phones in intensive care units, just to be prudent. The bigger issues seem to be with the annoying calls themeselves, discussing privite issues in halls and rooms needs to be addressed with all staff.
Today's Sun Sentinel stated that about 60% of the nearly 300 studies done on the effects of cell phone radiation have shown a damaging physical effect. Still think there's no correlation between cell phones and tumors? Try reading just a few of that 60% and see if you'd like to change your position.
Actually, this has been studied several times over the years. What's interesting is that most reports fail to learn from their predecessors. What is worse, however, is that medical device manufacturers fail to consider the ubiquity of portable/wireless communications devices, and work to reduce electromagnetic susceptibility to interference. It's do-able, but it would cost some time, effort and money, and might require some hardware redesigns.

Another issue is the allocation of frequency spectrum in the "Industrial-Scientific-Medical" bands. Essentially a license-free area, medical device manufacturers assume that, because of the nature of their equipment, they can effectively ignore other users or interference that might occur, quite legally, from other regions of the spectrum.

It's not so much time to tell everyone to stop using their portable electronics, as it is time for the medical device manufacturers to perform the due diligence to operate complex, safety-of-life equipment in today's world.

Finally, I've a friend in the broadcast engineering business in the Dallas, TX area. When the first digital television signals went on the air, cardiac telemetry units around the Dallas area went off-line. The problem? The TV station was operating in a licensed channel for digital TV, but a number of hospitals had FCC-derived secondary spectrum ISM allocations (unlicensed) that were also in the range of that channel. Was it the TV station's fault? Hardly: First, they were licensed as a primary user of that spectrum. Second, they had advertised their intent, including the date and time the first digital signals would go on the air, for weeks. In my opinion, the hospitals failed to take due notice of the information provided, and once again, the medical device manufacturers failed to note that they were pre-positioning hardware to operate in spectrum where they don't control.
The concern with cell phones on airplanes should be minimal. Each cell phone has its own frequency, which at best would jam audio to or from a pilot. Seeing that airlines and cell companies have their own COMPLETELY seperate frequency ranges the chances of that are near impossible. Not to mention that airplanes radios are far more powerful than any cell phone. Compare it to your radio completely changing stations while on the same setting because one station has a stronger signal. Millions of people fly everyday and many use cells regardless of regulations, have you every heard of a plane crashing because of that??? NO should be your answere and the safe bet is that it will NEVER happen
Dr. Gupta,
In your hospital, do any of the nurses or physicians use cell phones provided by the hospital? I am a senior resident in Emergency Medicine in an extremely busy ED, and our hosptial cell phones are a necessity. We page consultants, PCPs, call radiology, call the lab -- all while in perpetual motion. Occasionally a resident does not get a phone, and must page people to the main line. When they call back, the call gets dropped, the resident is in the room with a patient and doesn't hear the overhead, or has to keep running out to answer calls. Some of our consultants even refuse to call if we give the main number, as they know they will have to sit on hold for a long while.
I have not yet read the Dutch study, although I will. I have never experienced any significant equipment malfunction, and many of our attendings and administrators have told us the cell phone issue is just a myth.
On the other hand, today by coincidence, I didn't realize that I had my own personal cell in my bag. I usually never bring it into the hospital. I was seeing a patient in the ICU when my bag suddenly started playing my very loud rock song ring tone. I couldn't even find it to shut it off. I was mortified! That never should have happened - so I certainly agree that there is a time and place for everything.
Food for thought...right before my cell phone rings or receives an instant message, my computer speakers will create a loud static sound like AM radio someitimes emits. That's how I know my phone will ring before it even rings. The cell is usually in my purse underneath my desk at work about 3 to 4 feet away. If it can affect my computer speakers like that (happens at home too when I have the cell on my desk), I can only imagine what else it affects. Anyone else experience this?
I am an RN and I work on a telemetry floor. We carry in-house cell phones and I absolutely hate it. I think it is extremely rude to be in a patients room and have to answer a call. But if I don't answer, the calling party gets very annoyed with me.
Almost all of the nurses I work with carry a personal cell phone as well and spend lots of time talking on them. Some do take pictures of each other, which could be a problem if witnessed by a patient or family member.
Several years ago we had an incident where an electronic toy disrupted our monitor signals. It lasted for the better part of the shift. We have a new monitor system now, and have had no problems with cell phones, computers, or toys.
Before I comment, I would like you to know that I am a fan of yours and send you relentlessly any information on health and nutrition I gather for my blogs or my newsletter or my websites.

I have been following the debate about electromagnetic fields, cell phone towers and cell phones - thank you for letting us know of our responsibilities around sensitive medical equipment.

My comment relates to this sentence in your blog:

"My hospital, for example, allows no usage, whereas other places may be more liberal. A good rule of thumb, though, is to probably turn off your phone entirely when in intensive care units, emergency rooms and near operating room suites."

Shouldn't the responsibility be shared. i.e. shouldn't the hospital protect the equipment by installing products which help prevent the effects of EMF not only on the body, but perhaps on the equipment? And not only rely on people turning off their phones,as there might be some who just would not?

Of course, the jury are still out on the health effects of cell phones, cell phone towers, wireless devices...

After all the seminal WHO study quoted widely was done in 1993 before cell phones exploded to more than 2 billion, before usage was the exclusive domain of young people and minorities, before people opted to rely solely on the cell phone to the exclusion of land lines...

Thank you for your vigilance on this topic. Looking forward to an up to date study on health effects...
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