What's the radiation risk from airline flying?
- By Joe Pappalardo
- AirSpaceMag.com, November 01, 2007
The aurora borealis signals an incoming solar storm.
NASA
Flying involves inherently dangerous elements—complex mechanical equipment, harsh environments, crowded airspace. Air & Space reader Jon Day asks about an additional risk for frequent fliers: radiation exposure.
Because Earth's atmosphere shields us from cosmic radiation—the denser the atmosphere, the greater the protection—flying in the upper, thinner portion of the atmosphere increases your radiation exposure. The amount doubles with every 6,000 feet of altitude.
Day asks: "For typical altitudes in international flying, how much flying is too much?" Two organizations—the U.S. National Council on Radiation Protection and Measurements and its global equivalent, the International Commission on Radiological Protection—have established the radiation tolerance limits for air crews, the general public, and fetuses. A single, long international flight will expose you to a week's worth of natural background radiation. That's far from a health concern, even for pregnant women. But aviation workers can easily exceed the groups' recommended limits. For example, a pregnant flight attendant working a London-to-Chicago route for just 100 hours (about 12 trips) would exceed the safe exposure for her fetus. For air crews, the limit is 20 millisieverts (mSV) a year. (For scale, a person at ground level gets about 2.4 mSv of natural background radiation a year.)
The Federal Aviation Administration says these maximums are suggested, not mandated. The FAA's Advisory Circular 120-61, from 1994, recommends these limits for an air crew member: a five-year average dose of 20 mSv per year, with no more than 50 mSv in a single year. The European Union, using nearly the same standards, by law requires tabulations of exposure for air crew and limits the exposure to 20 mSv per year and 1mSv for fetuses.
In 1997, researchers from NASA's Langley Research Center in Virginia flew a modified Lockheed ER-2, a variant of the U-2 spyplane, with a spectrograph to measure the radiation exposure at altitudes between 52,000 and 70,000 feet. "Even though the exposure levels are higher at the higher cruise altitude, the typical flying public will actually receive less radiation exposure than on today's subsonic transports because of the higher speed," the researchers said.
The Concorde was the only commercial aircraft equipped with radiation dosimeters. It was an abundance of caution—the typical exposure can be calculated before the supersonic transport takes off. France's Civil Aviation Department takes the guesswork from the levels by operating an online calculator that can assess the level of exposure to those on board.
A solar flare can raise radiation levels. U.S. Department of Energy scientists extrapolated the exposure of a high-flying supersonic aircraft during the strongest known solar event—a 1956 solar flare—and concluded that the flare likely would have boosted exposure to 10 mSv per hour. If you're worried, consult with the solar weathermen at the Space Environment Center before flying.
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Comments (12)
Is there any difference in the altitude of a short European flight compared to that of a transatlantic flight.
Posted by James Greer on August 5,2008 | 09:39 AM
I have worked for a commericial airline for 25 years and am wondering if there is a means by which to be tested during a month of my flying. Thanks much!
Posted by Cheryl on October 1,2008 | 02:18 AM
RADTriageTM is a user-friendly radiation dosimeter for monitoring ionizing radiation (2-1,000 rads). When exposed to radiation the sensing strip instantly develops a permanent/irreversible color change which is cumulative and proportional to dose. RADTriageTM allows an individual to immediately self-assess the dose to which they may be subjected. EDITOR'S REPLY: The commenter is with the company that sells this particular model. Air & Space does not endorse one brand or model of dosimeter over any other.
Posted by Fay Crowe on December 13,2009 | 02:47 AM
Hi
I am wondering what type of radiation (millisieverts) I would receive if travelling from Charlotte NC to Brisbane Australia roundtrip? I am travelling with two young children- are recommendations for rad exposure different for young boys(1yr) or girls (4ys), we would like to travel back and forth to Australia each year.
Also is there anything that has shown to help repair damage caused by radiation exposure or protect during radiation exposure?
Thanks
Mary
Posted by mary vogen on July 12,2010 | 05:10 PM
I wonder if there is anything that has shown to help repair damage caused by radiation exposure. Thank you!
diane EDITORS' REPLY: Great question. Since the damage would occur to different kinds of cells throughout the entire body, it's unlikely that any medicine would have the capability to treat all of the genetic damage. But we are not biology experts here, so can't speak definitively.
Posted by Diane on October 10,2010 | 06:31 PM
I believe there are ways to mitigate the risk. Taking powerful antioxidants before, after and maybe even during should help. Turmeric has also been shown to cause cancer cell Apoptosis (cell death) A strong immune system is programmed to seek and, identify and destroy cancer cells.
Posted by Jonathan Marc on February 16,2011 | 04:48 PM
I am wondering what the increased risk of radiation contamination is due to the current events in Japan? In particular for a flight landing in Vancouver airport in B.C.. EDITORS' REPLY: We don't know. The levels of radiation are very likely to change in the coming days, depending on how many power plants are ultimately compromised (a situation currently in flux), how quickly the damage is repaired, etc., etc.
Posted by Dawn on March 14,2011 | 04:23 PM
Is their a risk of radiation exposure for flights due to Fukushima problems.
thank you
Posted by jenny on March 27,2011 | 10:33 PM
My daughter is flying from London to Texas she is 18 weeks pregnant. Will the radiation be safe for her and the baby? EDITORS' REPLY: We're not qualified to answer that, I'm afraid.
Posted by Margaret Pomeroy on May 11,2011 | 02:09 PM
This is really great information, but what is the relationships?
First, most people do not know what an Sv is, a milli-Sv or a micro-SV. An SV is 1, milli-Sv is 0.001, mirco-SV is .000001.
What is an Sv, look here:
http://en.wikipedia.org/wiki/Sievert
The USA uses REM (Roentgen Equivalent Man) which converts 1 Sv = 100 rem.
What does that mean to the ordinary person on the street that has no knowledge or background in radiation. That for example a CNN broadcaster that was covering the Japan nuclear disasters or a US Congressman, lets go with the Congressman.
During a Congressional hearing, the "experts" stated that the radiation dose one would experience in a flight for New York to LA was 2500 pico-rem. The Congressman stated, "I don't know about you, but I wouldn't want no 2500 pico-rem of radiation."
What is a pico-rem?
2500 pico-rem = 2.5 nano-rem = .0025 mirco-rem = .0000025 milli-rem = .0000000025 rem. Wow, that is pretty small number compared to 2500.
Look up Roentgen(http://en.wikipedia.org/wiki/R%C3%B6ntgen) and you'll find this info:
"An acute whole-body dose of under 50 rem is typically subclinical and will produce nothing other than blood changes."
"50 to 200 rem may cause illness but will rarely be fatal."
"Doses of 200 to 1,000 rem will probably cause serious illness with poor outlook at the upper end of the range."
"Doses of more than 1,000 rems are almost invariably fatal."
Notice these are whole numbers, no decimal points, milli, micro, nano or pico.
So, if 1,000 REM is fatal, how does 2500 pico-rem compare?
Lets use dollars.
Comparing 1000 REM (letal dose) to .0000000025 REM (NY to LA filight) is like comparing 25 cents to $100,000,000,000.00 (that's 100 billion dollars).
Want to "know" the effects of radiation and radiation exposure, look it up yourself and learn about it.
Posted by Leonard Suschena on July 5,2011 | 01:54 PM
I looked into this quite a bit as my wife is a flight attendant.
There are a few very good sources to calculate your actual dosage on a flight available on the Internet, one of which is http://jag.cami.jccbi.gov/cariprofile.asp . There are also sites that will email you in real time if there are any solar flare events.
But basically a cross country airplane trip is roughly equivalent to a chest x-ray. Background radiation over a year is about 5 (sea level) to 10 times (Denver) that.
Posted by David on October 20,2011 | 12:10 PM
Has anyone measured the amount of radiation absorbed in the new Boeing 787 using composite material instead of aluminum?
Posted by Thomas Downey on January 28,2013 | 10:26 AM
Does synthetic material of 787 increase radiation exposure?
Posted by T.Downey on February 12,2013 | 10:03 PM