Wednesday, April 12, 2006

Airplane radiation graph with a geiger counter, MDW to LAX

A recent flight to Los Angeles had great results. Halfway through the flight the pilot announced he was dropping from the 38,000ft cruising altitude to 30,000ft to avoid persistent turbulence (in my notes I wrote 36,000ft but it can be difficult to hear what the guy was saying, and I think the data shows a better match to 30,000ft). The data were taken once a minute.

I also added to the graph a yellow line showing the background rate in my office which is 7.5 microrads/hr. So flying at 38,000ft gives you a rate about 40 times greater than here in my quiet little office in Chicago.

I've previously done this on trips to Los Angeles: Dean W. Armstrong: Geiger Counter

In the past I've also looked at potassium salt, Pentax Takumar lenses, dinosaur bones, and have a live report of radiation rates from my office.


Kristin said...

How about taking your Geiger counter over by the bananas in the Hyde Park Co-op? As you might imagine, I'd be very curious about how that would look.

Anonymous said...

i work as a flight attendant and i often wonder how much radiation i get monthly. my flights are usually from east to west coast!! i am helping my son with a science experiment for school where i am taking a dental x-ray with a penny paperclipped to it...we will expose the x-ray soon and see what happens...i saw your site and find it really interesting

Sean said...

Were these readings taken midday or night?
How much does solar radiation add to the levels?

Dean W. Armstrong said...

The horizontal axis of the graph has time in Central Daylight Time on it. It was evening.

The literature says approximately 1/3 of the cosmic ray input to the Earth is from the Sun. When the Earth encounters a mass ejection from the Sun or a flare occurs on the Sun much more radiation can be produced.