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Sentinel Chicken · 03-29-2002, 11:17 PM

Well that's all fine and dandy, but I get a kick out of how some of these so-called safety groups use scare tactics to forward their agendas. This article lacks any context in which to evaluate let alone understand the risks of radiation exposure in flying compared to everyday activities.

First of all there are three ways to measure radiation- activity (how much something radiates energy based on molecular decay), radiation exposure (how much the air is ionized by a given radiation), absorbed dose (how much radiation is absorbed by a given mass of an object) and dose equivalent (measure of the biological effect of radiation).

It's that last measurement that really matters medically, the dose equivalent, which is measured in rems (Roentgen equivalent man) or sieverts (SI units, more common now, abbreviated as Sv).

The current standards in radiology if I'm not mistaken is no more than 5 rems/yr, which equals 0.05 Sv/yr (and that comes from the Nuclear Regulatory Commission). That comes out to 50000 microSv/yr to use the same units as this article does. The average medical x-ray ranges between 50-200 microSv. Most chest x-rays are only 80 microSv, so their assertion that 50 chest x-rays is the limit seems suspect based on what I've seen. I ain't so good at math, but that adds up to 625 chest x-rays per year.

The article talks about getting 63 microSv of exposure on the EWR-HKG flight over the North Pole. Now take a look at dose equivalents in everyday life for comparison:

*Chest x-ray: 80 microSv
*Extremity x-ray: 10 microSv
*Dental x-ray: 100 microSv
*Lumbar spine x-ray: 1300 microSv
*CT scan: 11000 microSv
*Drinking water: 50 microSv/yr
*Cosmic radiation at sea level: 260 microSv/yr
*Terrestrial background radiation (this is usually from radon and other rocks in the ground): 150-400 microSv/yr
*Your own body produces low levels of radiation as well that add up to about 390 microSv/yr
*Using natural gas at home: 90 microSv/yr
*Television sets: <5 microSv/hr
*Use of consumer products: 100 microSv/yr

Bottom line, you're going to get just as much, if not more radiation exposure just in daily life as you would flying on a long-haul commercial flight.

ROCK CHALK JAYHAWK!

03-29-2002, 11:17 PM	#3
Sentinel Chicken Go-Getters Go Ozark Join Date: Jan 2001 Location: DFW/THE GREAT STATE OF TEXAS Posts: 4,167	Well that's all fine and dandy, but I get a kick out of how some of these so-called safety groups use scare tactics to forward their agendas. This article lacks any context in which to evaluate let alone understand the risks of radiation exposure in flying compared to everyday activities. First of all there are three ways to measure radiation- activity (how much something radiates energy based on molecular decay), radiation exposure (how much the air is ionized by a given radiation), absorbed dose (how much radiation is absorbed by a given mass of an object) and dose equivalent (measure of the biological effect of radiation). It's that last measurement that really matters medically, the dose equivalent, which is measured in rems (Roentgen equivalent man) or sieverts (SI units, more common now, abbreviated as Sv). The current standards in radiology if I'm not mistaken is no more than 5 rems/yr, which equals 0.05 Sv/yr (and that comes from the Nuclear Regulatory Commission). That comes out to 50000 microSv/yr to use the same units as this article does. The average medical x-ray ranges between 50-200 microSv. Most chest x-rays are only 80 microSv, so their assertion that 50 chest x-rays is the limit seems suspect based on what I've seen. I ain't so good at math, but that adds up to 625 chest x-rays per year. The article talks about getting 63 microSv of exposure on the EWR-HKG flight over the North Pole. Now take a look at dose equivalents in everyday life for comparison: Chest x-ray: 80 microSv Extremity x-ray: 10 microSv Dental x-ray: 100 microSv Lumbar spine x-ray: 1300 microSv CT scan: 11000 microSv Drinking water: 50 microSv/yr Cosmic radiation at sea level: 260 microSv/yr Terrestrial background radiation (this is usually from radon and other rocks in the ground): 150-400 microSv/yr Your own body* produces low levels of radiation as well that add up to about 390 microSv/yr Using natural gas at home: 90 microSv/yr Television sets: <5 microSv/hr Use of consumer products: 100 microSv/yr Bottom line, you're going to get just as much, if not more radiation exposure just in daily life as you would flying on a long-haul commercial flight. ROCK CHALK JAYHAWK!* __________________ *Piss on noise abatement!* Last edited by Sentinel Chicken; 03-30-2002 at 12:29 AM.