RADON TEST SPRUCE STUDY GUIDE EXAM
2026 QUESTIONS WITH SOLUTIONS GRADED
A+
◉ Rn. Answer: Radon, part of the Uranium decay chain
◉ RDP. Answer: Immediate decay product of Rn: Polonium, Lead, and
Bismuth
◉ Rn measurement units. Answer: picoCuries per liter (pCi/L) in the
U.S., Becquerels per cubic meter (Bq/m3) internationally
◉ Alpha particles. Answer: Most massive, slowest moving, and least
penetrating type of radiation
◉ Beta particles. Answer: Smallest mass type of radiation
◉ Gamma rays. Answer: No mass, fastest moving, and deepest
penetrating type of radiation
◉ Half-life. Answer: Amount of time required for one-half the atoms in
a sample to decay
,◉ Rn half-life. Answer: 3.8 days
◉ Rn. Answer: Group A Carcinogen, known to create cancer in humans
◉ Epidemiological Studies. Answer: Comparisons of indoor Rn
concentrations in homes of lung cancer victims and non-lung cancer
persons
◉ Linear no-threshold risk model. Answer: Assumes any radiation dose
increases the risk of cancer proportionately
◉ Rn exposure. Answer: Cumulative (chronic) risk, greater for smokers
and children
◉ Rn transport mechanisms. Answer: Advection, diffusion, emanation,
and well water transport
◉ Causes of air pressure differences. Answer: Indoor/outdoor
temperature differences and mechanical equipment
◉ Mechanical ventilation. Answer: Can impact indoor Rn
concentrations in different ways
,◉ Homes served by private, drilled wells. Answer: May have elevated
indoor Rn due to radon in water transport
◉ Indoor Rn concentrations. Answer: Commonly highest near the
source (e.g., ground-contacted rooms)
◉ Measurement protocols. Answer: Short-term and long-term testing
deployment
◉ Closed-building conditions. Answer: Required for short-term tests,
including specific instructions
◉ Proper Test Location(s). Answer: Determining if the device was
located in an appropriate room
◉ NRPP certified/State licensed person. Answer: Determining if the test
was conducted by a certified/licensed individual
◉ NRPP approved device. Answer: Determining if the measurement
device was approved by NRPP
◉ Differential pressure. Answer: Pressure needed to overcome stack and
mechanical effects
, ◉ Estimate airflow needs. Answer: Based on vacuum cleaner test
◉ Identify need for multiple suction points. Answer: Determining if
multiple points are required for effective mitigation
◉ Identify barriers to sub-slab communication. Answer: Recognizing
obstacles that prevent effective communication
◉ Recognize sub-slab hazards. Answer: Identifying potential dangers in
the sub-slab area
◉ Select membrane type. Answer: Choosing the appropriate membrane
based on specific requirements
◉ Select soil gas collector type. Answer: Choosing the appropriate
collector for soil gas
◉ Design interconnections of vent piping. Answer: Determining how
multiple crawlspaces are connected
◉ Treat inaccessible crawlspaces. Answer: Addressing crawlspaces that
are difficult to access
2026 QUESTIONS WITH SOLUTIONS GRADED
A+
◉ Rn. Answer: Radon, part of the Uranium decay chain
◉ RDP. Answer: Immediate decay product of Rn: Polonium, Lead, and
Bismuth
◉ Rn measurement units. Answer: picoCuries per liter (pCi/L) in the
U.S., Becquerels per cubic meter (Bq/m3) internationally
◉ Alpha particles. Answer: Most massive, slowest moving, and least
penetrating type of radiation
◉ Beta particles. Answer: Smallest mass type of radiation
◉ Gamma rays. Answer: No mass, fastest moving, and deepest
penetrating type of radiation
◉ Half-life. Answer: Amount of time required for one-half the atoms in
a sample to decay
,◉ Rn half-life. Answer: 3.8 days
◉ Rn. Answer: Group A Carcinogen, known to create cancer in humans
◉ Epidemiological Studies. Answer: Comparisons of indoor Rn
concentrations in homes of lung cancer victims and non-lung cancer
persons
◉ Linear no-threshold risk model. Answer: Assumes any radiation dose
increases the risk of cancer proportionately
◉ Rn exposure. Answer: Cumulative (chronic) risk, greater for smokers
and children
◉ Rn transport mechanisms. Answer: Advection, diffusion, emanation,
and well water transport
◉ Causes of air pressure differences. Answer: Indoor/outdoor
temperature differences and mechanical equipment
◉ Mechanical ventilation. Answer: Can impact indoor Rn
concentrations in different ways
,◉ Homes served by private, drilled wells. Answer: May have elevated
indoor Rn due to radon in water transport
◉ Indoor Rn concentrations. Answer: Commonly highest near the
source (e.g., ground-contacted rooms)
◉ Measurement protocols. Answer: Short-term and long-term testing
deployment
◉ Closed-building conditions. Answer: Required for short-term tests,
including specific instructions
◉ Proper Test Location(s). Answer: Determining if the device was
located in an appropriate room
◉ NRPP certified/State licensed person. Answer: Determining if the test
was conducted by a certified/licensed individual
◉ NRPP approved device. Answer: Determining if the measurement
device was approved by NRPP
◉ Differential pressure. Answer: Pressure needed to overcome stack and
mechanical effects
, ◉ Estimate airflow needs. Answer: Based on vacuum cleaner test
◉ Identify need for multiple suction points. Answer: Determining if
multiple points are required for effective mitigation
◉ Identify barriers to sub-slab communication. Answer: Recognizing
obstacles that prevent effective communication
◉ Recognize sub-slab hazards. Answer: Identifying potential dangers in
the sub-slab area
◉ Select membrane type. Answer: Choosing the appropriate membrane
based on specific requirements
◉ Select soil gas collector type. Answer: Choosing the appropriate
collector for soil gas
◉ Design interconnections of vent piping. Answer: Determining how
multiple crawlspaces are connected
◉ Treat inaccessible crawlspaces. Answer: Addressing crawlspaces that
are difficult to access
