Cancer Amongst Pilots

[BigginHillBoy]

Gentlemen.

Im thinking on these lines because three of my friends have been diagnosed with cancer lately. Im not at all convinced that radiation is to blame here (most likely coincidence?) but all those gentlemen are airline pilots. It also got me thinking about radiation because lately I had an x-ray done and my doctor used this massive led suit for protection. I know there has been some research and Id like to know the latest findings if some of you are educated enough to help me out. I have 4 questions:

1.Has it ever been proved that radiation is higher at jet altitudes (FL300 and up)?
2.If so, is this radiation strong enough to affect the health of people over time?
3.Is there any study that suggests cancer is more common amongs airline crews?
4.Do any airlines limit the number of flying hours for crew in regards to radiation?


I love flying – just like to know if we are taking this aspect of flying serious enough.
Thanks

[what next]

Hello!

The answer to questions 1, 2 and 4 is "Yes", regarding question 3 I have never heard about a relevant study.

Here in Europe, at least since the implemetation of JAR-OPS, crews of high flying aircraft are required to attend seminars on radiation risks at regular intervals (like CRM, dngerous good, firefighting and so on).

Greetings, Max

[HerrStiffler]

This probably belongs in the medical section, but worth reading none the less. What follows is one doctors opinion of x-rays and cat scans...

"
S&A HEALTH REPORT: The Danger of Detection
By Dr. David Eifrig Jr.
For the past two years, I have had the pleasure of staying at the Union League in Philadelphia for a week, while attending an annual review course sponsored by the University of Pennsylvania. This year, as last year, the pressure to learn was intense. The daily lectures began at 7:15 a.m. and ended approximately 12 hours later! Lunch was provided, but often the scheduled time to eat was shortened because the morning lecture didn't end on time. Whew… I learned a lot, but most of it is still sinking in. By the way, if you ever get a chance to learn about the history of the Union League, I encourage you to do so. Its motto is "Love of Country Leads." It was founded in 1862 as a society to support President Lincoln. It is a fascinating place and the employees are about as loyal as any I have ever met. The Union League is to the movers and shakers of American politics as The Augusta National is to golf.
Okay, enough of the travel diary and on to the point. One of this year's speakers at the review course reminded us of something he said last year. I had apparently ignored it last year, but this time it hit home in a big way.
According to David Abramson, the first-ever Chief of the Ophthalmic Oncology Service at Memorial Sloan-Kettering Cancer Center, "Diagnostic X-rays cause close to 1% of all deaths in the U.S., and 3.5% of all deaths in Japan." Moreover, he told us, "You should never let a child get a CT". A CT, or computer tomography, is essentially a large number of consecutive or serial X-rays taken all at once and then analyzed by computers using fancy algorithms. This was jaw-dropping because I myself have ordered hundreds of CTs on adults and children. It turns out that terminal cancers that occur years later are not easily traced back to the earlier exposures.
Suspicions that radiation from X-rays and CTs cause long-term health problems have been around for a long time. But because the cancers are slow-growing and insidious, it has taken a long time to uncover the real risks. Only in the past 10 years have scientists truly questioned the benefits versus risks of detection via CT or X-ray.
What this means for you and me is unclear, but for us as a group the dangers are real. Researchers at Columbia University put the risk for getting cancer at 1 out of 1,000 from exposure to radiation from the now-commercially available whole-body scans. In addition, the false positive rates from these machines are high. This means that the scan finds anomalies that are not truly disease-causing or debilitating. The anomalies don't need treatment, but they show up on the scans as "positive." On top of this, these whole-body tests are usually hyped as health-promoting when, in fact, they are not. Even worse, they are expensive.
What is scary, though, is that the studies your doctor might order could easily be useless as well as dangerous. Yet, we trust our doctor to make these decisions. Be careful. Is your doctor ordering tests to help with diagnosis, or to CTA (Cover Their A**)? You see, even if the CT were to pick up a true disease entity (for example, prostate cancer), there is very little evidence that early detection in certain diseases (especially slow-growing ones) makes any difference in quality or length of life. For those with a disease detected early and no symptoms, the psychological impact of knowing you have a disease can be spiritually and physically devastating. It is possible that the psychological impact is more devastating than the disease would be, and could lead to earlier morbidity and mortality. In fact, a Mayo study of lung-cancer screening found that people in the screening group died earlier than those not screened with CTs. Hmmm.…
In a Japanese study, CT screenings flagged equal numbers of smokers and non-smokers for lung cancer. Thus, CTs failed as a screening tool for cancer in smokers, and worse, put many people at risk for cancer from the radiation exposure of the CT.
The confounding variable in all this is that doctors are taught to do things based on assigning value to a result. So ordering a test and acting on it becomes a very natural step for doctors. Sometimes they act even if the result is logically flawed. Surprisingly and dangerously, treating a false positive from a lab or test result is quite common. Ironically, the real problem comes when doctors treat a false positive and, seeing improvement, assume falsely the treatment worked.
This statistic will blow you away: After 10 yearly mammograms for women 50 years old or older, the cumulative false positive rate rises to almost 50%. What! How can this be so? Your doctor certainly won't tell you this. Does your doctor even know? And what happens is that the poor woman is exposed to more radiation and more risk of cancers as the doctor tries to figure out whether she really does have the disease. The key is to assess the risk clinically before exposing a woman to radiation. The math is slightly complicated, but by stratifying patients in to pre-test probabilities for disease…the correct and, hopefully, safest test might be ordered.
The fact is that CTs and the haphazard recommendations to get them when the clinical signs and symptoms don't warrant them are inexcusable. Just recently I read of a child getting head CTs when the clinical suspicions were quite low. The poor child's head was only exposed to the CT radiation because of the parents' prodding and the doctor's fear. Again, this is exposure that has been shown to lead to cancer, and could have been prevented by informed and fearless parents and doctors. Sadly, most doctors will argue that they have to order them to avoid being sued, commonly saying that they've never been sued for ordering a test, only for not ordering one.
When it comes to radiation... What do I do?
1.
I avoid radiation for myself whenever possible.
2.
I do not let dentists X-ray my mouth.
3.
I do not get chest X-rays for a long-standing cough since I am not a cigarette smoker.
4.
When considering a CT in a child, I think long and hard about this and discuss the very real dangers with the parents. If the clinical picture fits, the CT usually is unnecessary.
5.
If a doctor ever recommended a CT, I would request an MRI (these are currently thought to be safer than the radiation from CTs).

Here's to our health,
David Eifrig Jr., M.D., M.B.A.
"

[James T. Kirk]

I once took a small Geiger counter to work with me to do my own experiment. I flew from London to Hong Kong then from Hong Kong to Melbourne and back.
I found a marked increase in radiation above FL250 above which level increases in radiation became roughly linearly proportional to altitude. Radiation was also proportional to latitude being much higher at higher latitudes falling at lower altitudes with a very marked drop when crossing the equator.
My Geiger counter only measured ionising radiation ( Alpha & Beta ) so Gama and X-ray didn’t register at all. I would post the figures here but they were all lost when I upgraded my PDA, sorry. As I recall the radiation levels never quite reached published danger levels but they weren’t far away.
I do have anecdotal evidence however that the levels on aircraft are high enough to cause concern in other industries. I used to work in atomic energy research. A colleague of mine took his family on holiday to Florida. He inadvertently packed his film badge dosimeter in his suitcase. He discovered it while on holiday but thought little of it. Some time after his return to work a routine test of film badges in his section almost caused an emergency shut down of the site. The radiation he had collected on his two sectors was enough to indicate a possible leak in one of the reactors.
Kirk out…

[what next]

Hi!

I did a little google search and found these two refences to studies that both link the occurrence of cancer among pilots to the frequent disturbance of the biological rhythm of the body rather than to the higher radiation levels:

http://news.bbc.co.uk/1/hi/health/645113.stm

and

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10817375&dopt=Abstract

Greetings, Max

[Maude Charlee]

So turboprops are good for your health after all?

[J.O.]

Of course! You'll live a longer and healthier life, you just won't be able to hear your grandchildren's laughter! :}

Just kidding of course. I love my turboprop buddies. They always give me a nice ride to the next gateway.

[GlueBall]

Ever heard of "Medical & Health" . . .14th Forum from the top :eek:

[llondel]

My local dentist has a notice up about dental x-rays where they point out that you get a bigger dose of radiation flying to Spain and back than you do from one of their x-rays.

[Flyit Pointit Sortit]

At the risk of sounding condecending, do you think that the High levels of radiation exposure mentioned above have anything to do with the luggage going through x-ray security machines. But for the record Our Company OPS Manual has 4 pages on Cosmic radiation exposure but not much on sleep deprevation:ugh:

[Dani]

There is not only the issue of radiation and irregular sleep as a health risk. I do also know a lot of collegues who live a very unhealthy lifestyle in general: Eating, drinking, lack of body exercise, high body mass index, smoking, promiscuity, stress etc. Do you want to know more?

Pilots are in general more conservative people, less influenced by new fashions and ideas, and therefore somewhat immune to new movements in health and living.

Dani

[hetfield]

@Dani

and others.

All true!

Check the slowfood-people. Founded in Italy.

http://www.slowfood.de/

[Sl4yer]

Some research suggests they may not be:

http://news.bbc.co.uk/1/hi/sci/tech/5173310.stm

The programme suggested that levels of cancer amongst airline pilots should be much higher than they are, if the existing Linear No Threshold model is correct.

[blue up]

NRPB published a report describing why us pilots are classed as radiation industry workers and therefore permitted to have a higher annual dose of radiation compared to 99% of the public. Basically, we'd never do more than 2 months a year if kept to the normal limits. Still low quantities but it makes for an interesting read. One day in (IIRC) the early 1970s you could have had an entire years-worth of radiation in one 8 hour sector at FL330+ from northern Europe to North America. Something to do with sunspot activity and the higher doses received in higher latitudes.

Suggest you contact the NRPB (National Radiological something Board) for more details.

[Slats One]

The University of Iceland (Dr Rasmussen I think) published some leading peer reviewed papers in the late 1990s and early 2000s. There was some evidence that cosmic radiation on long haul flights presented a higher risk. A Swesish study found higher breast cancer rates (than normal background levels) in Swedish female aircrew.

The Concorde flight crews had their fare share of acute myeloid leukemias and cancers- notably prostate. Military cancer rates are higher too- both these groups operate at FL40 -55 +.

The higher you go, the bigger the risk - short duration or long.

Lufthansa implemented a protocol on flight and cabin crews to reduce long haul exposure by mixing and matching long haul crews with short haul work.

The experts I know are predicting long term cosmic radiation effects on crews after 10 -15 years of the ultra-long haul A3340/380 fligths ie SIN-JFK.

But then the radiation levels on the ground in Cornwall are pretty high chaps...And frankly you are more at risk from pesticide residues in your cheap and nasty, clean and bright, supermarket food and the parabens in mens and womens toileteries - especially underarm deoderants...

Flying is safer ...

[arcniz]

Something to do with sunspot activity and the higher doses received in higher latitudes.

A fact little recognized in statistics (because it is inherently non-statistical) is that radiation doses from extra-terrestrial sources (the main factor in altitude flying) can vary from zip to phenomenal at any time and place. The natural rad sources in space - whether exploding galaxies or just radiation hot-spots on the sun that spin around to point at earth for days, hours, or seconds - can vary over an energy range of 1,000,000x or more.

High ratios of variation apply to surface radiation levels as well (a point to ponder in relation to 'global warming') but the proportional differences are especially notable high up where atmospheric filtering catches less of the incoming energy.

So it's another kind of lottery. Dosimeters might not be a bad idea for aircrew, but their use also might rock the employment boat more than one would want.

[DrKev]

During my degree in physics I had to take a course in radiological protection; while not in any way an expert in these matters, I do recall something very important - pilots do receive higher doses of radiation than the general public, due to cosmic radiation at high altitudes. The higher the altitude, the higher the dose of radiation. However, the yearly doses that pilots receive are well within the safety limits of occupational exposure. Only Concorde pilots (remember at 60,000 ft) flying London-New York return every day would exceed the recommended limits in a year, and no Concorde pilot ever flew every day for a year. (I believe it was in fact my lecturer at the time in Trinity College Dublin, Prof. I M McAuley who did this particular work on radiation exposure in pilots).

Where doctors and dentists are concerned they are exposed to x-rays every day. Long term low-level exposure under those circumstances is a different matter to what pilots receive, due to the nature of the radiation (x-rays vs cosmic rays) and the frequency of the exposure. Heavy lead lined aprons for health workers involved with x-rays is a common sense precaution and not related to radiation exposure for pilots.

For most people working in the airline industry, the additional cancer risks due to occupational exposure are small enough that other factors are much more important. Smoking, for example, makes occupational radiation exposure look very meek indeed. Other environmental factors, radon gas exposure in our homes coming up through the bed rock, is a much greater risk in many parts of many countries, Cornwall already mentioned.

To answer the original questions...

1.Has it ever been proved that radiation is higher at jet altitudes (FL300 and up)?
Yes.

2.If so, is this radiation strong enough to affect the health of people over time?
Not a yes or no answer. The doses received are well within occupational exposure limits. There may be an effect but is is comparable to other environmental health risks and much smaller than some.

3.Is there any study that suggests cancer is more common among airline crews?
I'm sure there are but it would be very difficult to conclusively link any increase in cancer to occupation radiation exposure. For example - do cabin crews smoke more than people in other occupations? Is there a statistically significant link to the number of hours worked and the increased risk of cancer?

4.Do any airlines limit the number of flying hours for crew in regards to radiation?
Not that I am aware of. I am also not aware of any need to.

[Five Green]

Dr. Kev.

4.Do any airlines limit the number of flying hours for crew in regards to radiation?
Not that I am aware of. I am also not aware of any need to.

Not true we here in Asia have a monitoring programme and crews are kept off the polar routes if they get above 6 something or others.

In addition to what arcniz mentioned. The affects of cosmic or solar radiation on humans has never been studied. All of the "Limits" suggested for flight crew are based on other forms of radiation. So basically we are flying guinea pigs.

FG

[DrKev]

The affects of cosmic or solar radiation on humans has never been studied. All of the "Limits" suggested for flight crew are based on other forms of radiation. So basically we are flying guinea pigs.

This is not actually true. Cosmic particles hitting the upper atmosphere (far above where aircraft can fly) causes cascades of other particles toward the ground. Those particles and their interactions are well known so we actually do know something about the effects on humans. Secondly, exposure limits always err on the side of safety - if we did not know how cosmic or solar radiation affects humans we would assume a worst case scenario and set the exposure limits based on that until better information is obtained. To say we are flying guinea pigs is simply incorrect.

[arcniz]

So basically we are flying guinea pigs.
In a manner of speaking, we ARE all guinea pigs - as have been our ancestors and precursors in evolution for thousands of millions of years.

The earth has a cosy skin of atmosphere and a powerfully protective magnetosphere to somewhat dilute the quantity and intensity of incoming ionising radiation. Cruising above a portion of that protection in the stratosphere definitely increases exposure, but the effect is not simple to intuit or measure. Depends on age, gender, diet, genetics and probably a fair amount of luck whether a particular cosmic particle will tear up a particular piece of DNA that will replicate and cause a particular cancer -- or not. Our DNA has learned from all that historical radiation to be very good at repairing itself - and at killing off improperly broken cells, so mama nature helps to mind the store even when we are in zipping around in our spaceships.

Pilots are very easy to identify and track for medical history purposes. So far there seems to be no persuasively documented 'smoking gun' of radiation-related diagnoses in fliers. This contrasts sharply with some workplace chemical exposures that leave an unmistakable trail of illness.

Is good to be cautious, but probably, as Dani says, the fatigue and stress connected with a flying career will get you - if not managed skillfully - long before the glow-in-the-dark stuff.

[blue up]

Five Green. I believe the proposed limit is 10 msv units (Milli or Micro Sieverts??) and that, by calculation and projection, pilots AVERAGE about 2 - 3 msvs per year. The 6msv limit sounds sensible since you'd have reason to be grounded if you got to 9msv.

Can dosimeters be bought? How much? IIRC, there are different types depending on which types of radiation you are expecting to have to measure.
Britannia Airways did some measuring of radiation exposure a few years ago but I'm not aware of the results.

[australiancalou]

I eared that drinking whisky and smoking cigarets counteract the effect of radiations or at least if you get a cancer you won't know if it's due to cosmic radiations or alcool.:} :} :}
In fact and more seriously it will be allways difficult to know exactly the origin of a diseases unless you know all of the facts you'll be facing artefacts.
From my point of view anyway I would not be surprised that man hide us the truth. Like paludism is not considered as a professional sickness irradiation will probably never be either.:E
Enjoy your flights............and moreover your drinks at arrival;)

[Semaphore Sam]

Just curious...given you fly x number of hours per year in the danger zones.
1. Are the rates of radiation higher in day than night, or is it a background thing?
2. Does blocking direct exposure of the sun to the skin make a difference? That is, putting newspapers, sunshades, etc up on the windscreen...does that help?

[DRDR]

Composition of cosmic radiation:
93 % protons
6.4 % alpha-particles (He-ions)
0.6 % other ions like Li, B and Bi

Enegry of cosmic radiation:
100000000 eV to 100000000000000000000 eV

Due to their very high enery these ions create secondary radition when entering the earths atmosphere. From 4 km to 20 km this secondary radition does mainly consist of electrons, positrons and photons.

Shielding:
Alpha particles will be absorbed by a sheet of paper. Of course this depends on their energy. But I am confident that ions will be absorbed by all the metal around you.

Eletrons and positrons on the other way will not be entirely absorbed by a piece of paper. You would need some layers of metal. Most of them will probably be absorbed by all the stuff around you. So I would not worry too much about them too.

Unfortunately photons (also called gamma rays or x-rays) are more or less unimpressed by all the stuff around you. You would need massive shields (for example thick lead sheets) to get rid of them. So you will be bombarded by photons when flying around. These photons will produce tertiary radiation when colliding with other atoms (e.g. in you body) which then can create damage to you DNA. The amount on damage depends on the mass and energy and biologic material. A good indicator is the amount of energy these particles deposit in you body multiplicated by a factor depending on the particle. This will get you an energy in the unit Sievert (Sv).

Now you will get these photons when being on the ground. So the question is, how much more energy you will get when flying around in the stratosphere.

If you are sitting around (which means you are not working with nuclear materials) you will get 2.4 mSv in a year. These are 0.0024 Sv.

Now let's compare:

teaching nuclear physics one year 0.00001 Sv
sitting around one year 0.00240 Sv
x-ray stommach 0.00380 Sv
smoking one year 0.00880 Sv

Results in you body:

changes in blood 0.2500 Sv
temporary radiation sickness 1.0000 Sv
really serious radiation sickness 4.0000 Sv
death 8.0000 Sv

Of cours if you get 0.25 Sv in 10 years you will not get blood changes. But if you get them in a short time, you will probably get them. But it's not that easy to say how short the time should be. In any way you should think about adding the energies over time. At the moment we assume a linear relationship between energy dose (Sv) and the probability for cancer. Although this can probably change when looking at small amounts of energy.

Allowed exposure in one year:

people working in exposed areas 0.0200 Sv
anybody else 0.0100 Sv

Life long exposure limit for exposed workes:

0.400 mSv

Conclusion:

If I would be flying around professionally (I am not, I am just teaching around;-), I would make the following calculation:

Energy dose "available" for flying aournd, assuming that I want to become 100 years old:

0.400 Sv - 100 x 0.00240 Sv = 0.1600 Sv

Then I would take a look at the online calculator for energy doses:
http://jag.cami.jccbi.gov./cariprofile.asp

This gives me a dose of 0.0001 Sv for a 40.000 ft 12 hour flight from FRA to LAX in February.
Which means that I could do this flight

0.1600 Sv / 0.0001 Sv = 1600 times

That sounds a lot, but you know better than I how many flights you do in your professional life. And please beware, that energy doses can be much higher when...

...flying higher
...flying during solar activity
...flying northern (on northern hemisphere) or southern (on southern hemisphere)

Suggestion:

Take the FAA energy dose calculator (URL provided above) and log your exposure before each flight. You will then be able to know when you have exceeded the official lifetime limit.

I hope all of this made any sense... Greetings, DRDR.

[Graybeard]

Hmm, the DC-10 and 747 classic would be safer for the SLF, as they carry a ton of sheet lead in the sidewalls, for noise insulation. The 727 had a lot, too. By now, however, most of it has probably been removed to save weight.

GB

[4Greens]

If you google on Ian Getley you will get up to date research by Ian and the University of New South Wales on radiation. He is a current Qantas Captain and measures radiation in flight.

[bri1980]

Classified radiation workers (working in hospitals and nuclear plants) are permitted no more than 20 milliSv per working year (so 9mSv is fairly low).

To put this into context, if you live near Sellafield, the background radiation averages 2 mSv per year, whilst in Cornwall the background count is about 8 mSv per year.

Pregnant women have a much lower dose limit, but I can't remember it.

Dose meters may be obtained through National Radiation Protection Board (UK). I think you have to have some training though-might be worth checking.

The relevant regulations are Ionising Radiation Regulations (1999).


Didn't Concorde used to have a radiation monitor?

[Setpoint99]

A good overview on aviation dose (circa 2000 but still valid on the basics) is here:
http://ans.org/pubs/magazines/nn/vi-2000-1

[rob-d]

I came across this study a while ago when looking into cancer rates amongst airline pilots. It is a study of cancer occurances in Nordic Airline pilots over a 50 year period.

http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=124549

[main gear touchdown]

Similar study for Cabin Crew in Europe
http://aje.oxfordjournals.org/cgi/content/full/158/1/35

and for cockpit crew 1967-1997
http://www.epidem.com/pt/re/epidemiology/abstract.00001648-200211000-00014.htm

[Boneman]

I do not get chest X-rays for a long-standing cough since I am not a cigarette smoker

So what do you do for a long standing cough? Many things other than smoking can cause lung cancer.

[tarik123]

Do anybody know if weather radar might have any affect on
operating crew, we know it will harm people who are infront
but how about the people who are literally sitting on top of the
radar during any given flight??

[arcniz]

Do anybody know if weather radar might have any affect on
operating crew,

Rather like those extraordinarily powerful energy pumps on the wings, the idea of the airbourne radar is that the supplies go in one end and the focussed energy goes out the other.

In normal operation, very little energy leaks from the onboard radar. A cellphone in one's shirt pocket probably emits 10,000x more free microwave radiation than one is likely to encounter coming from a properly working aircraft radar package, including all components from power supply to the radome.

If something is not properly connected or is otherwise malfunctioning, microwave energy may leak out where it should not be. Such conditions likely will appear as a system malfunction. If not, they are likely to be located during periodic system checks.

Standing in front of operating radar units is not advisable, but that is difficult to experience with aircraft radar. Larger aircraft have interlocks that prevent operation on the ground. Small aircraft with radar have skillful pilots who remember to leave it in standby until underway.

Of course, a little tinfoil (or lead) in one's cap is a optional precaution. When it begins to heat up for no clear reason, leave the area asap!

[blue up]

IIRC, my 757 allows the use of Wx radar whilst on the ground.

[arcniz]

IIRC, my 757 allows the use of Wx radar whilst on the ground.

Certainly there are cases for using radar on the ground - perhaps to see what's inside a giant purple thing in the sky at end of the departure runway on a no-wx airfield. An aid for zero-zero taxi, maybe?

But it is not so nice to paint persons and buildings with high-power focus-beam microwaves while taxiing or parked. Might sort out the discount-price pacemakers real fast, along with some other dramatic negatives.

Wonder if your 757 makes you override something to paint with the radar when on the ground, or if it automatically limits power, inclines the beam, or just doesn't distinguish the case?

[DRDR]

Microwaves are NOT ionizing radiation. And microwaves are reflected by metal (therefore metal dishes are used for focusing them). So if you are sitting behind the antenna you do not have to worry about biological effects (heating your body e.g.).

[arcniz]

Microwaves are NOT ionizing radiation.

Good point! The dangers of microwave beams come mostly from two mechanisms:

a) Induced electrical currents - troublesome per se in electronic circuits and other conducting objects where the 'stray' electricity can do bad things.

b) Induced heating - in less conductive materials... such as flesh, eyeballs, etc. Exactly what the consumer microwave oven is intended to do to food in a controlled space.

Some researchers also believe that recurring electromagnetic fields induced in tissue, nerves, etc. can alter normal biological mechanisms enough to cause cell abnormalities and possible disease. This is the common thread in most concerns about cellphone antennas radiating close to the body. No broad consensus exists yet in this regard, but frequent problems are not evident.

[beardy]

This
http://solarb.msfc.nasa.gov/science/space_weather/impacts/AirCrews.pdf

is an interesting link.

[astinapilot]

See this link for Demron, a radiation "proof" fabric. Apparently light weight. Why could this not be incorporated into a/c linings or even the flight deck linings? Blankets for crew rest? That would halve the exposure. $$ I imagine.

http://www.radshieldstore.com/

I fly s/h but had a mate at QF and they were limited to 1 route per month over the poles. This was about 5 years ago.

From other reading I have done the most exposure seems to be in the cockpit, cabin is more safe due to cargo underneath and more metal above.

Thoughts?

[Crashnburn22]

We all learned in our ATPL's that at 40 000ft the air is 25% that of the surface, meaning you only have 25% of the protection from cosmic radiation. So yes, you definately are at more risk.

I know above 52 000 ft aircrew must wear a radiation badge and strict limits apply to how many hours they're allowed to fly over a period of time. Doesn't really help us though!!

[Graybeard]

Here's what I posted on the Tech log on 31 March, re: Wx Radar and Health:

The old Wx radars use a magnetron for power, on the order of 60,000 watts peak power - in pulses. That is about 700 watts average power, same as a full size microwave oven, which also uses a magnetron. You may worry about your Wx radar on a walkaround, but how about the microwave oven in the lounge that was made by semi-slave labor to questionable compliance with industry standards?

The solid state radars, beginning in about 1980, typically are less than 150 watts peak power - less than one watt average power, so you will be hit in the head by the swinging antenna before you are close enough to be exposed to significant radiation.

Even with high power Wx radar, you would have to be running it facing a steel wall to have enough power mirrored into the cockpit to matter. Wx radar will not penetrate metal. Sidelobes in modern flat plate antennas and radomes are almost nonexistent, and with the advent of forward looking windshear systems, their sidelobes have been suppressed to zilch.

While you nervous nellies are fixating on the Wx radar, largely because of its name, do you put the TCAS and DMEs in standby while on the ground? They are typically in the realm of 500 watts peak power, and a decent walkaround will get you up close to them.

One way to know if the Wx radar in your DC-x or old Boeing or A300B4 is magnetron or solid state is to note warmup time. If not already in standby, a magetron takes up to a minute or more to warm up and begin transmitting. Solid state radars are instant on.
GB

[DRDR]

Although it has nothing to do with cosmic radiation or ionizing radiation at all I undertook the effort to compare the power of various transmitters:

bluetooth: 0.001 W to 0.1 W
wireless LAN: 0.1 W to 1 W
cordless DECT phone: 0.250 W
radar altimeter: 0.500 W
cell phone: 2 W
mobile analog radio: 4 W
amateur radio: 25 W to 750 W
cell phone tower: 50 W
TCAS: 250 W
civil marine radar for small boats: 2000 W
aircraft weather radar: 35 W to 12000 W
tv radio antenna: 100000 W

While 250 W from TCAS antennas sound like a lot of power, these antennas radiate in all directions. So these 500 W become relative again, compared to 500 W radiated from a unidirectional source like a weather radar.

In any way: From a physicists point of view common sense would dicate to shut down high power antennas when humans are working around them. Because like mentioned before although radio waves (radar, microwaves, UHF, VHF, ...) do not ionize you atoms, they heat your body. While heating your stomach is probably not that dangerous, heating your eyball is. :ouch:

Power Point concerning weather radar:

http://www.itu.int/ITU-R/study-groups/seminars/rwp8b-radar/slides/2.1-ICAO-EUROCONTROL-RTCA-Biggs.ppt

[Arrowhead]

The key point is this (harking back to my physics degree)...

Alpha radiation is stopped by a single sheet of paper
Beta radiation is stopped by thin piece of foil or a window
Gamma radiation is virtually unstoppable

In other words, the aircraft skin or windows will stop alpha and beta radiation, and gamma (ionising) radiation is almost as likely to reach you at low altitude as at high.

My top tips to avoid cancer in aviation:
1) Turn off transponder, DME, radalt, and other transmitters while doing the walkaround - and dont transmit on COM
2) Wear suncream and hat while doing walkaround on a sunny day
3) Avoid x-rays where poss since these give you more radiation than in flight
4) Stop smoking
5) Eat lots of fresh fruit and veg

[grimmrad]

HERR STIFFLER QUOTED A REPORT FROM A MD:
Quote:
1. I avoid radiation for myself whenever possible.
2. I do not let dentists X-ray my mouth.
3. I do not get chest X-rays for a long-standing cough since I am not a cigarette smoker.
4. When considering a CT in a child, I think long and hard about this and discuss the very real dangers with the parents. If the clinical picture fits, the CT usually is unnecessary.
5. If a doctor ever recommended a CT, I would request an MRI

-------------------

I completly agree with 1 and 2. 1 is obvious, 2 it seems that especially in the US the dentists are very trigger-friendly i.e. everyone gets an x-ray, which is absolutly useless.
As for number 3 - if it is a long standing cough I would get an X-ray as please don't forget: non-smokers get lung cancer as well (less often though) and it could be related to some other kind of oulmonary disease that requires diagnosis and treatment (Sarcoidosis, metastasis, TBC, pneumonia to name a few).
4 and if the benefit outways the risk I get a CT for my kid (e.g. car accident, rule out cerebral hemorrhage)
5 you may ask if a MRI would do the trick as well. MRI is good for certain questions and CT is better for others. Leave it to the professional to decide which one is better but asking never hurts.

As for health risk related to flying PubMed shows 17 papers, one of the more recent and reliable one is this one:

Cosmic radiation exposure and cancer risk among flight crew.

Cancer Invest. 2004;22(5):743-61.
Sigurdson AJ, Ron E.
Radiation Epidemiology Branch, Division of Cancer Epidemiology and Genetics
National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland 20892-7238, USA.

Nearly 20 epidemiologic or related studies of cancer incidence and mortality have been published during or since 2000, with several reporting increased risks of female breast cancer among flight attendants and melanoma among both pilots and cabin crew. Occasionally, excesses of other cancers have been observed, but not consistently. Although the real causes of these excess cancer risks are not known, there is concern that they may be related to occupational exposures to ionizing radiation of cosmic origin. It is possible that confounding risk factors may partially or totally explain the observed relationships, but several investigations are beginning to address lack of past adjustment for reproductive factors and sun exposure with improved study designs. With progress in aviation technology, planes will fly longer and at higher altitudes, and presumably the number of flights and passengers will increase. To respond responsibly to the real and perceived risks associated with flying, more extensive data are needed, but special efforts should be considered to ensure new projects can genuinely add to our current knowledge.
PMID: 15581056 [PubMed - indexed for MEDLINE]

[C-N]

DRDR, ".. aircraft weather radar: 35 W to 12000 W tv radio antenna: 100000 W"

Weather Radar is obviously the strongest, reason why FC are required to turn this off on touchdown just before exiting the RWY. It would be interesting to know how many Watts the VOR's are transmitting as all enroute VOR are being overflown. These antennas will make you infertile.

Strange, as nobody mentioned regarding the diet of crew which are mostly composed of microwaved food. We know some countries already banned microwave oven, due to the proven studies that microwaved food becomes carcinogenic.

[DRDR]

Apparently VORs transmit with powers up to Kilowatts. But as UHF is non ionizing radiation I would not think that it makes you infertile. Esspecially while sitting in a an aluminium tube which is acting as a faraday cage.

Regardings microwave ovens:

The waves do not escape the oven. So don't worry. Although some microwave food does indeed look scary and is therefore probably troublesome... ;)

p.s.: Want to see a bad a** VOR? Take a look here: http://www.lancesanders.com/pix/newdfw.jpg

[Private jet]

A slight digression from radiation. I've not followed every link posted in this thread but i do seem to remember a study being carried out over many years on UK flightcrew. The results showed that crew have a significantly longer average lifespan than the population in general (can't recall the exact numbers but it is several years) This was attributed to the regular health "screening" (i.e medicals) throughout their working lives and the fact that many (but not all :}) try to pursue a healthier lifestyle in order to keep passing their medical. Interestingly the group that had the highest average lifespan were the flight engineers, who outlived pilots by 2 years.