I've used this comparison before: than airline pilots and flight attendents get more radiation (from cosmic radiation) than allowed nuclear power plant operators), but I had not seen it in print before.

This is from a UK study: results here are comparable: people in CO or UT (higher up) will get more radiation from the sky than I did working inside the shielding of the steel or concrete containment buildings at a nuclear power plant.

Now, remember, some amounts of radiation are natural, and if there were a catastrophic accident, obviously much, much more would be present near the accident than from cosmic radiation. This only talks about normal levels.

There are a couple of previous threads where this was discusssed in detail.. Also, how radiation behaves, how it can be prevented, and how it could be spread - and, more important, how it can be contained.

Look in the archives.

--- Friday, 10 December, 1999, 02:05 GMT Flying boosts radiation dose

High altitudes increase radiation exposure

Increased air travel is responsible for a jump in the amount of natural radiation to which Britons are exposed.

The official figures, from the National Radiological Protection Board (NRPB), come as separate research shows that airline pilots have more chance of developing one form of leukaemia.

It's surprising how few members of the public are aware of this cosmic radiation

Dr Michael Clark, NRPB

This is blamed on "cosmic radiation" from the sun, which is more intense at the altitudes reached by modern aircraft.

However, the increased risk of acute myeloid leukaemia was noticed only in pilots who had clocked up more than 5,000 flying hours in their careers.

Experts have stressed that even frequent flyers will not accumulate a high dose.

The NRPB's 1999 radiation dose review reveals that nuclear power workers, on average, now receive a lower annual average dose of radiation than aircrew.

Radiation doses (milli Seiverts)UK yearly dose 2.6Chest x-ray .02Fortnight in Cornwall 0.2Bag of Brazil nuts a week 0.2Jar of Mussels a week 0.25Frequent flyer 0.4 Overall, the average exposure of the UK population to radiation has stayed the same, due partly to decreasing exposure to "man-made" radiation.

The average UK dose is 2.6 milli Seiverts (mSv), but the highest average was in Cornwall, where naturally-occurring radioactive radon gas raises this to 7.8 mSv.

A frequent flyer aloft for around 100 hours a year would receive an additional annual dose of approximately 0.4 mSv.

Medical procedures increase radiation doses Dr Michael Clark, a scientific spokesman for the NRPB, said: "It's surprising how few members of the public are aware of this cosmic radiation.

"But even frequent flyers get doses that are within the acceptable normal ranges."

The study, published in the Lancet, examined Danish male jet cockpit crew flying more than 5,000 hours.

The researchers estimated that such crew members receive up to nine mSv a year.

Out of 3,877 crew, 169 developed cancer, compared to 153 in a similar-sized sample of non-pilots.

The pilots suffered more cases of skin cancer, but this was explained by the theory that many spent more time than non-pilots in sunny climes.

The increase in leukaemia cases was described as "significant" - and the researchers suggested that as airline pilots may be naturally more healthy than the average person, the risk may even have been underestimated.

However, they said the increase did not represent a "major effect".

Other studies

Four other studies have shown increased cancer mortality in pilots, and one found a higher incidence of breast and bone cancer in female cabin crew who had been flying for more than 15 years.

One, involving Air Canada pilots, showed an increase in acute myeloid leukaemia.

However, a study carried out by British Airways showed that its pilots and flight engineers had a reduced risk of dying from cancer.

The airline has installed cosmic radiation monitors in its flagship aircraft Concorde, which flies at much higher altitude than conventional aircraft.

Because the flight is far quicker, passengers and crew under normal circumstances would receive a lower dose than on a normal flight, but in times of abnormally high radiation levels, such as during a period of solar flares, the pilot may be warned to reduce height.

As much as 85% of the average annual radiation dose comes from natural sources.

Half the "natural" exposure comes from exposure to radioactive radon gas, with the rest from internally produced radiation, small levels of uranium and other radioactive substances in soil and rocks, and cosmic radiation.

"Man-made" sources are mostly medical x-rays and CT scans, with less than one per cent coming from nuclear discharges, fallout from nuclear testing in the 1960s and radioactive paint used on "glow-in-the-dark" watches.

Search BBC News Online

Advanced search options BBC ONE TV NEWS WORLD NEWS SUMMARY See also:29 Jun 99 | Health Flights radiation warning 05 Jul 99 | Health Dental scanner could cut X-ray threat 19 Mar 99 | Health Depleted uranium 'low risk' for Gulf veterans 04 Jul 99 | Health Experts target skin cancer 03 Dec 99 | Health Pylons safe, says 'definitive' research Internet links:National Radiological Protection Board The Lancet British Airways The BBC is not responsible for the content of external internet sites Links to other Health stories are at the foot of the page.

-- Robert A. Cook, PE (Marietta, GA) (cook.r@csaatl.com), December 10, 1999

Answers

It's easy to forget that the earths crust is radioactive.

Work in a building with a lot of granite in the floors and walls? Your getting an extra chest X-ray or two of radiation per year.

Coal fired power plants bury 1100 lbs of Thorium every year in the fly ash. And that's what they scrubbed out of the stack. How much went into your air? Didn't read about that while you were worried about the leak of 10 millicuries of radioactive iodine from the local nuculear power plant did you.

Not to minimize the problems (and radioactive Iodine can be a problem) but sometimes it needs to be put into perspective.

-- LM (latemarch@usa.net), December 10, 1999.

Just WHAT is this dude saying...that those of us who stockpile Brazil Nuts will glow in the dark???

-- K. Stevens (kstevens@ It's ALL going away in January.com), December 10, 1999.

No, no.

Only that you get some radiation from the Brazil nuts internally as they passed through your system .....

On one of our surface ships I was on a (long time ago) - the captain and executive officer received more radiation on their exposure meters - because they were topside, closer to the cosmic radiation, near the bridge above the steel decks and reactor shielding - than the nuclear operators did.

The nukes were down lower in the ship, well below decks and so had more shielding.

-- Robert A. Cook, PE (Marietta, GA) (cook.r@csaatl.com), December 10, 1999.

but of course since all these frequent flyers are travelling closer to the speed of light than stationary persons, they do not age as fast.

I'm sure this tradeoff is more than enough to offset the potential harmful effects of increased cosmic radiation. ;^)

-- plonk! (realaddress@hotmail.com), December 10, 1999.