Radon Flashcards
Radon
Radioactive decay product of uranium
Stable product at end of Uranium decay series
Lead
Difference between radon and radium
Radon: gas
Radium: solid
Most notable effect of radon on humans
Lung cancer
How does radon effect the body to cause cancers
Alpha particles have so much energy that it strips electrons away from atoms that make up your body
Why is radon hard to detect
Colourless, odourless
How long does Mike Holmes recommend to leave Rn testing units in place for
91 days
Maximum acceptable level of Rn to Helath Canada
200 Bq/m3
How much does a Rn test cost
$250
How does Rn enter a house
- from groundwater through foundation
- from well water
- from soil into cracks or windows
Bq (becquerel)
Measure of radioactivity
1 Bq
activity of a quantity of radioactive material in which one nucleus decays per second
Fraction of homes in Calgary with Rn higher than Health Canada limit
1/8
Homes built in the last 25 years have higher Rn content on average because
More square footage, taller, more airtight
Percentage of lung cancer in Canada attributed to Rn
16%
Minerals that contain U and Th, where can they be found
Zircon, uranite, monazite
Found in igneous, sedimentary , and metamorphic rocks
How do U and Th-bearing minerals get through the earth
- fractured bedrock leaches Rn into limestone
- limestone to sand and gravel
- sand and gravel to fractured clay
- fractured clary to sand and silt
Most of Alberta is a relative Rn hazard of
Zone 1 - high
Highest Rn levels in homes of Calgary area found in
Cochrane
Why is Rn higher in some areas
- abundance of U and Th minerals in bedrock
- grain size and permeability of bed rock
- amount of fractures in bedrock
- U and Th minerals in glacial sediments
Kind of rock in Southern Alberta glaciated in the past
Sandstone, siltstone, mudstone
Main source of Rn in homes
Rn in soil
Plays an important role in soil Rn potential
Soil permeability
Strong positive associations between the soil radon potential and
percentage of homes above 200Bq/m3
