RADON EXAM PREP QUESTIONS AND
ANSWERS WITH COMPLETE SOLUTIONS |
GARDED A+ | NEW UPDATE 2025
What are Properties of Radon? - ANSWERS Radioactive, inert gas, naturally
occurring, denser than other gasses, odorless, colorless, and tasteless.
Basic Parts of an Atom are what? - ANSWERS Nucleus, protons (+charge),
Neutrons (neutral) and Orbital Electrons (-charge)
Atomic Mass is what? - ANSWERS sum of protons and neutrons
Atomic Number is what? - ANSWERS # of protons
How are elements defined? - ANSWERS By the atomic # or the # of protons
How are different isotopes of an element distinguished? - ANSWERS By the
atomic mass
Any atom with 86 protons is called what? - ANSWERS Radon
What is the most common and most stable isotope of radon? - ANSWERS Rn
222
,What is an isotope? - ANSWERS An atom of the same element, but having
different number of neutrons. *All radon isotopes have 86 protons in the nucleus
The term "half life" means - ANSWERS The time required for HALF (not all) of
the atoms to decay
What is an ion? - ANSWERS an atom that has either lost or gained electrons
creating a net positive or negative charge
How are RDPs (Radon Decay Products) measured? - ANSWERS Working Levels
(WL)
Radon Decay Products (RDPs) - ANSWERS Solid particles of heavy metals,
short lived RDPs are most significant, have static charges, chemically reactive, and
source of cell damage to the lungs
What is Equilibrium Ratio (ER) ? - ANSWERS The ratio of all RDPs a particular
Rn Concentration can produce versus the % of those RDPs that are suspended in
the air (where they are measurable)
What is the Equilibrium Ratio (ER) assumption? - ANSWERS The ER typically
stays between 0.3 to 0.7 (30% to 70%) because of plate out. For any given
concentration of radon, it's assumed half of the RDPs have stayed airborne and
the remainder have plated out (an ER of 50%)
What is EPA's Radon Action Level? - ANSWERS 4.0 PCi/L
, How many U.S. homes have levels at or above the EPA's action level? -
ANSWERS 1 in 15 U.S. homes
What is the average radon indoor level? - ANSWERS 1.3 PCi/L
What is the average radon outdoor level? - ANSWERS 0.4 PCi/L
Lung Cancer Induction - ANSWERS Radon gas & RDPs are inhaled, RDPs remain
stuck to lung tissue, alpha particles strike lung cells, causing physical + / or
chemical damage to DNA
Scientific Basis for Radon Risk Estimates - ANSWERS Studies on underground
miners, committee on the biological effects of Ionizing Radiation (BEIR), National
Academy of Sciences and NRC, Studies of Residential occupants, pooling of North
American (NA) residential studies, pooling of European (EU) residential studies,
NA, EU & Chinese studies - pooled together
According to ANSI-AARST Standards, no worker shall be exposed to more than
how many WLM in a 12 month period? - ANSWERS 4 WLM
WLM = - ANSWERS The average WL concentration times hours exposed
divided by 170 hours in a working month
What is the range of actual induced deaths in the U.S. per year? - ANSWERS
15,000-22,000 per year
ANSWERS WITH COMPLETE SOLUTIONS |
GARDED A+ | NEW UPDATE 2025
What are Properties of Radon? - ANSWERS Radioactive, inert gas, naturally
occurring, denser than other gasses, odorless, colorless, and tasteless.
Basic Parts of an Atom are what? - ANSWERS Nucleus, protons (+charge),
Neutrons (neutral) and Orbital Electrons (-charge)
Atomic Mass is what? - ANSWERS sum of protons and neutrons
Atomic Number is what? - ANSWERS # of protons
How are elements defined? - ANSWERS By the atomic # or the # of protons
How are different isotopes of an element distinguished? - ANSWERS By the
atomic mass
Any atom with 86 protons is called what? - ANSWERS Radon
What is the most common and most stable isotope of radon? - ANSWERS Rn
222
,What is an isotope? - ANSWERS An atom of the same element, but having
different number of neutrons. *All radon isotopes have 86 protons in the nucleus
The term "half life" means - ANSWERS The time required for HALF (not all) of
the atoms to decay
What is an ion? - ANSWERS an atom that has either lost or gained electrons
creating a net positive or negative charge
How are RDPs (Radon Decay Products) measured? - ANSWERS Working Levels
(WL)
Radon Decay Products (RDPs) - ANSWERS Solid particles of heavy metals,
short lived RDPs are most significant, have static charges, chemically reactive, and
source of cell damage to the lungs
What is Equilibrium Ratio (ER) ? - ANSWERS The ratio of all RDPs a particular
Rn Concentration can produce versus the % of those RDPs that are suspended in
the air (where they are measurable)
What is the Equilibrium Ratio (ER) assumption? - ANSWERS The ER typically
stays between 0.3 to 0.7 (30% to 70%) because of plate out. For any given
concentration of radon, it's assumed half of the RDPs have stayed airborne and
the remainder have plated out (an ER of 50%)
What is EPA's Radon Action Level? - ANSWERS 4.0 PCi/L
, How many U.S. homes have levels at or above the EPA's action level? -
ANSWERS 1 in 15 U.S. homes
What is the average radon indoor level? - ANSWERS 1.3 PCi/L
What is the average radon outdoor level? - ANSWERS 0.4 PCi/L
Lung Cancer Induction - ANSWERS Radon gas & RDPs are inhaled, RDPs remain
stuck to lung tissue, alpha particles strike lung cells, causing physical + / or
chemical damage to DNA
Scientific Basis for Radon Risk Estimates - ANSWERS Studies on underground
miners, committee on the biological effects of Ionizing Radiation (BEIR), National
Academy of Sciences and NRC, Studies of Residential occupants, pooling of North
American (NA) residential studies, pooling of European (EU) residential studies,
NA, EU & Chinese studies - pooled together
According to ANSI-AARST Standards, no worker shall be exposed to more than
how many WLM in a 12 month period? - ANSWERS 4 WLM
WLM = - ANSWERS The average WL concentration times hours exposed
divided by 170 hours in a working month
What is the range of actual induced deaths in the U.S. per year? - ANSWERS
15,000-22,000 per year
