[I]t might be helpful to consider something called the banana equivalent dose (BED). This is a term used in physics to measure the amount of radiation emitted by a banana. It is a number popular with people who think the dangers of radiation are exaggerated, and who use it to make the point that almost everything is radioactive. A dental x-ray has a BED of 50; serious radiation poisoning takes a BED of 20m; sleeping next to someone for one night has a BED of 0.5 and living within 50 miles of a nuclear power plant for a year has a BED of 0.9.
Since 9/11, 53 people have been killed by terrorists in the UK. Every one of those deaths is tragic. So is every one of the 26,805 deaths to have occurred on Britain's roads between 2002 and 2012 inclusive, an average of 6.67 deaths a day. Let's call that the SDRD, standard daily road deaths. The terrorist toll for 12 years comes to 0.0121 SDRD. This means that 12 years of terrorism has killed as many people in the UK as eight days on our roads.
John Lanchester was invited by Alan Rusbridger to review some of the Snowden files and report on his findings in the Guardian. He has has written a superb analysis of the files and the concerns they raise.
I hadn't heard of a banana equivalent dose before reading the article but I'd like to highlight it for three reasons.
The first is that I believe that Lanchester is right. The risk of terrorism does not justify the powers that have been surreptitioisly granted to the NSA or to GCHQ. Nor does it justify the rights that have been taken away from the British and American people, largely without their knowledge or consent. I think that Laughton's analysis—along with Bruce Schneier'sappeal for openness—is one of the best things I've read since the Snowden files were first revealed. His use of the banana equivalent dose is one of the reasons I found his argument so persuasive.
The second reason is that over the last four or five years, I've become very interested in health and fitness. I'm one of the many people that find things like calorie counting and alcohol units both confusing and difficult to keep track of. Nuclear scientists think in sieverts. Nutritionists think in calories, but the rest of us don't. Something like like a banana equivalent dose might make it easier for us to understand and keep track of how much we're eating and drinking.
The third reason is the usefulness of something like a banana equivalent dose when doing a risk analysis. It establishes an easily understood and agreed-upon baseline. It's often hard to understand what we're measuring unless we have something to compare it to.