## March 14, 2011

Goatguy adjusted the scale of the EPA radiation chart. Original chart is below.

The average person in the United States receives about 360 mrem every year whole body equivalent dose At low doses, such as what we receive every day from background radiation, the cells repair the damage rapidly. At higher doses (up to 100 rem), the cells might not be able to repair the damage, and the cells may either be changed permanently or die. At even higher doses, the cells cannot be replaced fast enough and tissues fail to function. An example of this would be "radiation sickness." This is a condition that results after high doses to the whole body (over 100 rem), where the intestinal lining is damaged to the point that it cannot perform its functions of intake of water and nutrients, and protecting the body against infection. This leads to nausea, diarrhea and general weakness. With higher whole body doses (over 300 rem), the body's immune system is damaged and cannot fight off infection and disease. At whole body doses near 400 rem, if no medical attention is given, about 50% of the people are expected to die within 60 days of the exposure, due mostly from infections.

Health Risk Est. life expectancy lost

```Smoking 20 cigs a day                   6 years
Overweight (15%)                        2 years
Alcohol (US Ave)                        1 year
All Accidents                           207 days
All Natural Hazards                     7 days
Occupational dose (300 mrem/yr)         15 days
Occupational dose (1 rem/yr)            51 days
```
You can also use the same approach to looking at risks on the job:

Industry type Est. life expectancy lost

```All Industries                          60 days
Agriculture                             320 days
Construction                            227 days
Mining and quarrying                    167 days
Manufacturing                           40 days
Occupational dose (300 mrem/yr)         15 days
Occupational dose (1 rem/yr)            51 days
```

Sievert metric radiation unit at wikipedia

```* 1 Sv (Sievert) = 100 rem
* 1 mSv = 100 mrem = 0.1 rem
* 1 μSv = 0.1 mrem
* 1 rem = 0.01 Sv = 10 mSv
* 1 mrem = 0.00001 Sv = 0.01 mSv = 10 μSv
```

Counts per minute at wikipedia

* One becquerel (Bq) is equal to one disintegration per second, or 60 dpm.
* One curie (Ci) is equal to 3.7 x 10 10 Bq or dps, which is equal to 2.22 x 10^12 dpm.

The becquerel (symbol Bq) is the SI-derived unit of radioactivity. One Bq is defined as the activity of a quantity of radioactive material in which one nucleus decays per second.

The curie (Ci) is an older, non-SI unit of radioactivity equal to the activity of 1 gram of radium-226.

The conversion factors are:
```1 Ci = 3.7×1010 Bq
1 Ci = 37 GBq
1 μCi = 37,000 Bq
1 Bq = 2.70×10−11 Ci
1 Bq = 2.70×10−5 μCi
1 GBq = 0.0270 Ci
```

The original EPA chart