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SDHC ATP 4Gb Class 6 memory card review in Nuclear Power Plant Krško labs

Avtor:Matjaž Intihar
10.04.2007 21:56
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Gamma radiation data safety test

Most users will never come in contact with gamma radiation, but it’s good to know whether a memory card keep its data when it’s exposed to such radiation.

Gamma radiation is energetically very close to X-rays and, so the data on the card should be safe even after a prolonged stay in a medical X-ray facility.

Here is an Eberline Gamma calibrator 1000B. One X-ray exposure means approximately of 0.5mSv one-time, short dose of radiation. I exposed the card twice with five doses, which makes a total of 2x2.5mSv, 5mSv cumulative dose.

To illustrate this, the maximum allowed cumulative annual dose for the general population is 1 mSv. However, it is important to know that a single large dose has severely different effects than several smaller doses. As mentioned before, medical X-ray examinations range from 0.5 mSv in older machines to 0.2 mSv in new machines. While this doesn’t cause any measurable harm to the organism, there is no such thing as a safe dosage. On the other hand, chemotherapy dosages can go up to 2 Sv (200 times the allowed annual dosage), causing obvious symptoms, such as hair loss, nausea and other radiation sickness symptoms.

The first Chernobyl firefighters received doses of up to 20,000 mSv on their first day, resulting in a total of 47 deaths among them. At the moment, annual radiation exposure in the Chernobyl area is estimated to be between 10 to 20 mSv. Since the cards were exposed to one half to one quarter (5 mSv) of that dosage in a matter of minutes, it’s safe to assume that even if you fancy holidays in Chernobyl, you won’t lose your data.

 

 


Eberline gamma source

 


Starting condition

 

 


Second dose received, approx. 2.5mSv

 

 


The Kodak card retained all data.

 

 

 


The ATP card kept all data without losing it.

 

 

Both cards (Followup)kept data after relatively high doses. A conclusion can be drawn – there’s no need to worry about our pictures when we pass through airport scanning devices. Also we know that we can make pictures in a medical X-ray facility. With film, this was always risky. Worrying about whether our pictures can survive an X-ray scan is a thing of the past. While the new X-ray scanners have a “film safe” label, digital media is resilient even to those without the label.

 

 

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