Radiation Exposure : putting some perspective

Recent radiation leak from a stolen radiation canister releasing up to 300mSV/hour of gamma radiation is worrying. How could such a radioactive canister be compromised, from being transported in a car, to being stolen? Had it not been found and the need to publicise the story due to possible dangerous radiation sickness to those in the vicinity, this news may not have surfaced.

The information below gives some perspective to the amount of radiation that has leaked from this canister.

Source : http://www.health.com/health/article/0,,20410979,00.html

We absorb radiation from a variety of sources. How much is too much? Experts say 3 mSv per year is probably OK for most of us; 20 mSv for those who must have medical tests.

CT scan, full body 10–12 mSv
CT scan, chest or pelvis 4–8 mSv
Natural background radiation (from sunlight, radon gas, etc.) from living in high-altitude cities (e.g., Denver, Salt Lake City) 6 mSv (per year)
Natural background radiation from living at sea level (e.g., Chicago) 3 mSv (per year)
Mammogram 1–2 mSv
High-mileage frequent flying (100,000–450,000 miles per year) 1–6.7 mSv
X-ray of chest (or ankle to look for broken bones) 0.1–0.6 mSv
DEXA (bone-density) scan 0.01–0.05 mSv
Dental X-ray (bitewing) 0.02 mSv
Single airplane flight, coast-to-coast 0.01–0.03 mSv

Some of the possible effects of radiation.

Source : “Radiation Exposure and Contamination”. Merck Manuals. Retrieved 2 June 2013.

Of note 300 mSv / hour is equivalent to 0.3 Gray. So the duration of exposure is key to accumulating the amount of total radiation to the body.

Let’s hope that this is just an isolated incident.