22. Radon Flashcards
how is radon formed
radioactive decay of uranium and thorium
what does radon decay to make
it is radioactive
and it decays to make lead which is the most stable product
what are similarities between radon and radium
Both in the uranium-Pb decay series
both are radioactive
both cause cancers
Difference of radon and radium
Radium is a solid
Radon is a gas
what happens when someone breathes in excessive radon gas
particles embed themselves in lungs and stay there
continue to decay and radioactive decay causes problems in body
mainly lung cancer
what does radon emit
alpha particles that radiate so much energy that they strip electrons away from atoms that make up your body
what are some properties that make radon to detect
colourless, odourless
What is the second highest reason for lung cancer after smoking
Excess radon exposure
how long does mike holmes recomment leave radon test units in place
91 days
what is the maximum accetable level of radon according to health canada
200 Bq/m3
how much does a radon test cost
250
how does radon enter a house
shower
windows
cracks in basement
drain -> sumps
radon from groundwater
fractured bedrock then soil the plants
what is Bq (Becquerel)
measure of radioactivity
the activity of quantity of radioactive material in which one nucleus decays per second
Ionizing radiation
- calculated with transmission factors
- decreases with square of distance it travels
detection is in what dose and particle counts
gray, sievert
per second or minute
what fraction of homes in calgary have radon higher than the health canada limit
1/8
studies have found that homes built in the last 25 years have higher radon content. why
more square footage
taller
more airtight
approx cost of radon remediation
2500
what percent of lung cancer in canada is attributed to radon
16%
what minerals containt uranium and thorium
- Zircon ZrSiO4
substitute uranium for Zr in this crystal structure - Monazite (Ce,La,Th,Nd,Y)PO4
- Uraninite (UO2)
another name : pitchblende
found in all 3 types of rocks
how does U and Th minerals go up land
fractured bedrock
Limestone
sand and gravel
fractured clay
sand and silt
radon risk is high in which provinces
alberta and saskatchewan
which zone of relative radon hazard is calgary in
High: zone 1
which part of calgary has highest radon readings
NW - 125
why is radon higher in some areas than others
uranium and thorium minerals in bedrock
grain size and permeability of bedrock
amount of fractuers in bedrock
abundance of uranium and thorium in glacial sediments
southern alberta has alot of which type of rocks
Sandstone
siltstone
mudstone
was southern alberta glaciated in the past
yes, mostly glacier moved deposits called moraines
what was glacial episode like in alberta
20,000 years ago
Laurentide ice sheet met Cordilleran glaciers in rocky mountains. Met along a line passing through calgary
Erratics
rocks that were deposited during glaciation
where is glacial material sourced from
rocky moutains of west
Canadian shield of NE
what is SRP, soil radon potential
proportional to radon concentration in soil
higher the permeability of soil, higher the SRP
what is radon data show across canada about SRP
radon in soil is main source of radon in homes
soil permeability is important for soil radon potential
SRP can be an effective predictor of areas prone to elevated indoor radon concentrations
