Calculating your annual radiation dosage

Contrary to popular opinion, we are all constantly bombarded with radiation even when we are not in the presence of some sort of nuclear device or X-Ray. There are radioactive elements in the earth (uranium), in our food (potassium), in our air and water (radon), it's everywhere! I bet you would like to calculate how much radiation you get in a year, huh? Yeah, thought so.

Cosmic Radiation

Varies depending on the elevation at which you live, more
cosmic radiation is found at higher altitudes.

Sea Level:    26
0-1000 ft:    28
1000-2000 ft: 31
2000-3000 ft: 35
3000-4000 ft: 41
4000-5000 ft: 47
5000-6000 ft: 52
6000-7000 ft: 66
7000-8000 ft: 79
8000-9000 ft: 96

Terrestrial Radiation

Er, US only...

If you live in a state that borders the Gulf of Mexico or Atlantic Ocean, add 16
If you live in the Colorado Plateau (near Denver), add 63
Else add 30

Housing

If you live in a building made of concrete, stone, or brick, add 7.

Power Production

If you live within 50 miles of a nuclear power plant, add .01
If you live within 50 miles of a coal power plant, add .03

(Bet you didn't know that living near a coal power plant exposes you to
more radiation than a nuclear power plant, eh?)

From Food

Add 40 (on average)

From air

Add 200 (on average, from radon)

X-Rays/Medical Tests (per X-Ray or test)

Arm/leg/foot:           1
Dental:                 1
Chest:                  6
Pelvis:                65
Skull/neck:            20
Barium enema:         405
Upper GI:             245
CAT Scan:             110
Nuclear Test:          14 (thyroid scan, etc)

Misc

Weapons Test Fallout, add 1
Plane Travel, add .5 per hour in the air
Add .07 if you have porcelain crowns or false teeth
Add .06 if you wear a luminous watch
Add .002 for each time you go through an airport X-Ray
Add 1 if you watch TV
Add 1 if you are near a computer monitor frequently
Add .008 if you have a smoke detector in your home
Add .2 if you use gas lamps
Add 100 if you have a plutonium powered pacemaker (this is not a joke)

Now, add up your total. The score is in millirems, the unit of measure of radiation. The national average in the US is about 350 millirems. If you somehow manage to score over 5000, congratulations! You are getting more radiation exposure than nuclear power plant workers are legally allowed to get.

Fun Fact

On a cross country flight, you will recieve on average 3-5 millirems of radiation. This is more than you would recieve standing at the gate of a nuclear power plant 24 hours a day for a year.

Source: American Nuclear Society