RADON 2025 | 90 QUESTIONS AND ANSWERS
WITH COMPLETE SOLUTIONS
EPA recommends mitigation of radon at what level - ANSWER Greater than or
equal to 4 pci/l
EPA Home Buyer and Sellers Guide specifically deals with - ANSWER home
purchases and sales, and the potential for radon device interference
EPA recommends testing radon in - ANSWER the lowest level that could be
used regularly
What percentage of homes in the US have elevated radon levels - ANSWER 1
in 15
According to EPA - If you decide to finish or renovate an unfinished area of the
home in the future, a radon test should be done - ANSWER before starting the
project and after the project is finished.
According to EPA, what are 5 radon resistant features - ANSWER 1. Gas-
permeable Layer
2. Plastic Sheeting
3. Sealing and Caulking
4. Vent Pipe
5. Junction Boxes
, Gas‑Permeable Layer - ANSWER This layer is placed beneath the slab or
flooring system to allow the soil gas to move freely underneath the house. In
many cases, the material used is a 4-inch layer of clean gravel. This gas-permeable
layer is used only in homes with basement and slab-on-grade foundations; it is not
used in homes with crawlspace foundations.
Plastic Sheeting - ANSWER Plastic sheeting is placed on top of the gas-
permeable layer and under the slab to help prevent the soil gas from entering the
home. In crawl spaces, the sheeting (with seams sealed) is placed directly over the
crawlspace floor.
Sealing and Caulking - ANSWER All below-grade openings in the foundation
and walls are sealed to reduce soil gas entry into the home
Vent Pipe - ANSWER A 3- or 4-inch PVC pipe (or other gas-tight pipe) runs
from the gas-permeable layer through
the house to the roof, to safely vent radon and other soil gases to the outside.
Passive radon testing devices - ANSWER Passive radon testing devices do not
need power to function. These include charcoal canisters, alpha‑track detectors,
charcoal liquid scintillation devices, and electret ion chamber detectors. Collect a
time-weighted average and do not provide hourly readings
T or F Passive devices can used for short and long term testing - ANSWER True
Active radon testing devices - ANSWER Active radon testing devices require
power to function. These include continuous radon monitors and continuous
WITH COMPLETE SOLUTIONS
EPA recommends mitigation of radon at what level - ANSWER Greater than or
equal to 4 pci/l
EPA Home Buyer and Sellers Guide specifically deals with - ANSWER home
purchases and sales, and the potential for radon device interference
EPA recommends testing radon in - ANSWER the lowest level that could be
used regularly
What percentage of homes in the US have elevated radon levels - ANSWER 1
in 15
According to EPA - If you decide to finish or renovate an unfinished area of the
home in the future, a radon test should be done - ANSWER before starting the
project and after the project is finished.
According to EPA, what are 5 radon resistant features - ANSWER 1. Gas-
permeable Layer
2. Plastic Sheeting
3. Sealing and Caulking
4. Vent Pipe
5. Junction Boxes
, Gas‑Permeable Layer - ANSWER This layer is placed beneath the slab or
flooring system to allow the soil gas to move freely underneath the house. In
many cases, the material used is a 4-inch layer of clean gravel. This gas-permeable
layer is used only in homes with basement and slab-on-grade foundations; it is not
used in homes with crawlspace foundations.
Plastic Sheeting - ANSWER Plastic sheeting is placed on top of the gas-
permeable layer and under the slab to help prevent the soil gas from entering the
home. In crawl spaces, the sheeting (with seams sealed) is placed directly over the
crawlspace floor.
Sealing and Caulking - ANSWER All below-grade openings in the foundation
and walls are sealed to reduce soil gas entry into the home
Vent Pipe - ANSWER A 3- or 4-inch PVC pipe (or other gas-tight pipe) runs
from the gas-permeable layer through
the house to the roof, to safely vent radon and other soil gases to the outside.
Passive radon testing devices - ANSWER Passive radon testing devices do not
need power to function. These include charcoal canisters, alpha‑track detectors,
charcoal liquid scintillation devices, and electret ion chamber detectors. Collect a
time-weighted average and do not provide hourly readings
T or F Passive devices can used for short and long term testing - ANSWER True
Active radon testing devices - ANSWER Active radon testing devices require
power to function. These include continuous radon monitors and continuous
