Mitsumi
10th Apr 2002, 12:19
I know topic been done before but does this mean if aircrew fly 1000hrs a year we exposed to over 200 Xrays or four times the limit in other industries:
Radiation In The Skies
AWJ April 5-7 2002
Sandro Farina, just got more nervous about stepping on an airplane - and it's not because of security. The trading company executive recently learned from other fliers on the Web that his long-distance commute from Brazil to Hong Kong exposes him to something called cosmic radiation.
"I am really concerned," says Mr. Farina, who flies that route eight times a year.
Though not widely known, in-flight radiation is becoming a growing concern among researchers, crew members and the fliers who have to log thousands of kilometers a month. On any flight, radiation from stars penetrates the airplane, and experts say repeated exposure may be a health risk, similar to getting too many X-rays. The issue has not only led to changes at some airlines, but prompted the U.S. Federal Aviation Administration (FAA) to set up a new radiation Web site. And next year, the U.S. government, plans to release findings on the long-term effects on crew members, covering everything from miscarriages to cancer.
But radiation's impact on frequent travelers has remained largely ignored. So with high mileage fliers in, mind, we conducted our own world-wide flight test, taking two high-tech radiation monitors along on trips as long as 15 hours and as brief as 34 minutes. In all, we logged 61,000 kilometers, crisscrossing the globe at various latitudes, longitudes and altitudes to get different readings.
The result: We found it takes a great deal of flying before exposure becomes much of a concern. Still, if you travel between Asia and the U.S. a lot, take note of the Newark-Hong Kong route we took. It gave us our highest dose-about three chest X-rays' worth.
We also discovered that some shorter routes can actually expose fliers to more radiation than longer ones, and that doses rise quickly with altitude. (The higher you go, the less the atmosphere protects you.) Another issue: solar flares. During these rare occurrences, radiation levels can jump 20 to 100 times for as long as several hours.
To be sure, while our tests can be a guide for curious fliers, no one knows with certainty whether radiation is harmful at these levels. The U.S. government says the general public shouldn't be exposed to more than roughly 50 chest X-rays' worth a year from places like power plants and radiology offices (a level it estimates could cause cancer deaths in. four out of 100,000 people).
But workers in those industries can legally receive far more exposure. Based on our tests, you'd have to fly about 160,000 kilometers a year to reach that 50 X-ray mark.
For decades, scientists have wondered about radiation's effects on aviators, but the issue has been gaining momentum due in part to growing concern from airline workers. Two years ago, regulators in Europe began requiring airlines there to track crew members' exposure levels and educate them about the possible risks. In the U.S., the FAA has recommended that airlines educate crews about radiation (although only a few, including American and United, have produced brochures far them). And next year, the National Institute for Occupational Safety and Health plans to present new findings on the subject.
Though they acknowledge that cosmic radiation occurs, airlines and the FAA say they don't believe it's anything to worry about. The reason? The vast majority of fliers never come close to significant exposure. "There's no evidence to show that taking a few, flights a year makes any difference," says FAA radiobiology researcher Wallace Friedberg. (Only one carrier, United, disputed our findings, saying the readings were generally 10% to 15% high.)
Still, consumer advocates believe fliers need more information, particularly super road-warriors who are stuck in planes many times a week. "They're radiation workers," says Robert Barish, author of "The Invisible Passenger: Radiation Risks for People Who Fly" and a medical physicist. "They're not in the airplane for pleasure."
In fact, many people are checking into the issue themselves:, The FAA says as many as 1,500 people a month are using its Web site that calculates exposures on various routes. Some fliers are even tracking solar flares. "I was torn," says Marjorie McClelland, who postponed a flight to Kansas City, Missouri, due to one. "My dad thought I was being a sissy."
For our test, our machines took readings in microsieverts, a common unit of measuring radiation. Experts say 1,000 microsieverts is equal to about 50 chest X-rays. Below, our journey:
Newark-Hong Kong
KILOMETERS: 13,000
EXPOSURE: 63.4 microsieverts
This is the trip Continental flight attendant Jacqueline Jacquet-Williams tries to avoid. We didn't learn this, though, until we were aboard with the doors locked. "I don't know enough, but I worry," she says. "I try to get, rid of at least one of these flights a month because of radiation."
Just about a year old, this flight was one of a handful that U.S. airlines started steering over the North Pole, taking advantage of newly opened airspace over Russia. But that put us almost directly in the path of the strongest field of radiation above the earth. We fully expected our biggest dose on this 15 1/2-hour polar flight.
And that's just what happened: About eight hours into our flight, as our Boeing 777 jet nosed away from the Arctic Circle and passed over Siberia, our gamma reading reached its peak, about 3.1 microsieverts per hour. By the time we had touched down in Hong Kong, we had measured a dose of radiation equivalent to three chest X-rays. (According to Continental: "The scientific evidence that we've seen demonstrates that any increased health risk caused by cosmic radiation is statistically negligible.")
New York-London
KILOMETERS: 9,000
EXPOSURE: 42.9 microsieverts
At 6:30 in the morning, we passed the security checkpoint at New York's John F. Kennedy airport. In our carry-on: One Thermo Eberline 41H-B, to measure gamma rays, plus a Rembrandt neutron survey monitor, from Apfel Enterprises, to measure neutrons. As our gamma meter rolled through the X-ray scanner, its readings jumped.
By the time we hit our cruising altitude of 11,000 meters, where we'd remain for more than four hours, the gamma level was more than double what we had measured at the airport screening machine in other words, we were getting more gamma radiation per minute in the air than our luggage got in the X-ray machine back at Kennedy.
When we totaled it all up, we'd received the equivalent of two chest Xrays during this flight. "It's a little bit frightening," said Adam Brownstein, a Tokyo-based executive who flies about 160,000 kilometers a year.
Paris-Buenos Aires
KILOMETERS: 11,000
EXPOSURE: 36.2 microsieverts
Heading through the security checkpoint at Paris's Charles de Gaulle International, we were asked to explain the two electrical contraptions in our bag. "Oh, radiation," the guard nodded, waving us on. (While security personnel at New York's JFK examined our meters closely, we passed through security at most airports without question.)
On matters of radiation, this flight actually confirmed something scientists had told us: Airtime or distance isn't necessarily the biggest factor in determining exposure. Flights running closer to the equator, for instance, have extremely low doses. (The Earth's magnetic field pulls radiation toward the poles, making the extreme points of the globe the most radiation - intense.) So although this marathon flight was twice as long as our New York-London clocking in at 13 hours - it actually exposed us to less radiation than the route, which had taken us much closer to the North Pole.
-Robert J. Hughes contributed to this article.
Radiation In The Skies
AWJ April 5-7 2002
Sandro Farina, just got more nervous about stepping on an airplane - and it's not because of security. The trading company executive recently learned from other fliers on the Web that his long-distance commute from Brazil to Hong Kong exposes him to something called cosmic radiation.
"I am really concerned," says Mr. Farina, who flies that route eight times a year.
Though not widely known, in-flight radiation is becoming a growing concern among researchers, crew members and the fliers who have to log thousands of kilometers a month. On any flight, radiation from stars penetrates the airplane, and experts say repeated exposure may be a health risk, similar to getting too many X-rays. The issue has not only led to changes at some airlines, but prompted the U.S. Federal Aviation Administration (FAA) to set up a new radiation Web site. And next year, the U.S. government, plans to release findings on the long-term effects on crew members, covering everything from miscarriages to cancer.
But radiation's impact on frequent travelers has remained largely ignored. So with high mileage fliers in, mind, we conducted our own world-wide flight test, taking two high-tech radiation monitors along on trips as long as 15 hours and as brief as 34 minutes. In all, we logged 61,000 kilometers, crisscrossing the globe at various latitudes, longitudes and altitudes to get different readings.
The result: We found it takes a great deal of flying before exposure becomes much of a concern. Still, if you travel between Asia and the U.S. a lot, take note of the Newark-Hong Kong route we took. It gave us our highest dose-about three chest X-rays' worth.
We also discovered that some shorter routes can actually expose fliers to more radiation than longer ones, and that doses rise quickly with altitude. (The higher you go, the less the atmosphere protects you.) Another issue: solar flares. During these rare occurrences, radiation levels can jump 20 to 100 times for as long as several hours.
To be sure, while our tests can be a guide for curious fliers, no one knows with certainty whether radiation is harmful at these levels. The U.S. government says the general public shouldn't be exposed to more than roughly 50 chest X-rays' worth a year from places like power plants and radiology offices (a level it estimates could cause cancer deaths in. four out of 100,000 people).
But workers in those industries can legally receive far more exposure. Based on our tests, you'd have to fly about 160,000 kilometers a year to reach that 50 X-ray mark.
For decades, scientists have wondered about radiation's effects on aviators, but the issue has been gaining momentum due in part to growing concern from airline workers. Two years ago, regulators in Europe began requiring airlines there to track crew members' exposure levels and educate them about the possible risks. In the U.S., the FAA has recommended that airlines educate crews about radiation (although only a few, including American and United, have produced brochures far them). And next year, the National Institute for Occupational Safety and Health plans to present new findings on the subject.
Though they acknowledge that cosmic radiation occurs, airlines and the FAA say they don't believe it's anything to worry about. The reason? The vast majority of fliers never come close to significant exposure. "There's no evidence to show that taking a few, flights a year makes any difference," says FAA radiobiology researcher Wallace Friedberg. (Only one carrier, United, disputed our findings, saying the readings were generally 10% to 15% high.)
Still, consumer advocates believe fliers need more information, particularly super road-warriors who are stuck in planes many times a week. "They're radiation workers," says Robert Barish, author of "The Invisible Passenger: Radiation Risks for People Who Fly" and a medical physicist. "They're not in the airplane for pleasure."
In fact, many people are checking into the issue themselves:, The FAA says as many as 1,500 people a month are using its Web site that calculates exposures on various routes. Some fliers are even tracking solar flares. "I was torn," says Marjorie McClelland, who postponed a flight to Kansas City, Missouri, due to one. "My dad thought I was being a sissy."
For our test, our machines took readings in microsieverts, a common unit of measuring radiation. Experts say 1,000 microsieverts is equal to about 50 chest X-rays. Below, our journey:
Newark-Hong Kong
KILOMETERS: 13,000
EXPOSURE: 63.4 microsieverts
This is the trip Continental flight attendant Jacqueline Jacquet-Williams tries to avoid. We didn't learn this, though, until we were aboard with the doors locked. "I don't know enough, but I worry," she says. "I try to get, rid of at least one of these flights a month because of radiation."
Just about a year old, this flight was one of a handful that U.S. airlines started steering over the North Pole, taking advantage of newly opened airspace over Russia. But that put us almost directly in the path of the strongest field of radiation above the earth. We fully expected our biggest dose on this 15 1/2-hour polar flight.
And that's just what happened: About eight hours into our flight, as our Boeing 777 jet nosed away from the Arctic Circle and passed over Siberia, our gamma reading reached its peak, about 3.1 microsieverts per hour. By the time we had touched down in Hong Kong, we had measured a dose of radiation equivalent to three chest X-rays. (According to Continental: "The scientific evidence that we've seen demonstrates that any increased health risk caused by cosmic radiation is statistically negligible.")
New York-London
KILOMETERS: 9,000
EXPOSURE: 42.9 microsieverts
At 6:30 in the morning, we passed the security checkpoint at New York's John F. Kennedy airport. In our carry-on: One Thermo Eberline 41H-B, to measure gamma rays, plus a Rembrandt neutron survey monitor, from Apfel Enterprises, to measure neutrons. As our gamma meter rolled through the X-ray scanner, its readings jumped.
By the time we hit our cruising altitude of 11,000 meters, where we'd remain for more than four hours, the gamma level was more than double what we had measured at the airport screening machine in other words, we were getting more gamma radiation per minute in the air than our luggage got in the X-ray machine back at Kennedy.
When we totaled it all up, we'd received the equivalent of two chest Xrays during this flight. "It's a little bit frightening," said Adam Brownstein, a Tokyo-based executive who flies about 160,000 kilometers a year.
Paris-Buenos Aires
KILOMETERS: 11,000
EXPOSURE: 36.2 microsieverts
Heading through the security checkpoint at Paris's Charles de Gaulle International, we were asked to explain the two electrical contraptions in our bag. "Oh, radiation," the guard nodded, waving us on. (While security personnel at New York's JFK examined our meters closely, we passed through security at most airports without question.)
On matters of radiation, this flight actually confirmed something scientists had told us: Airtime or distance isn't necessarily the biggest factor in determining exposure. Flights running closer to the equator, for instance, have extremely low doses. (The Earth's magnetic field pulls radiation toward the poles, making the extreme points of the globe the most radiation - intense.) So although this marathon flight was twice as long as our New York-London clocking in at 13 hours - it actually exposed us to less radiation than the route, which had taken us much closer to the North Pole.
-Robert J. Hughes contributed to this article.