% of
Counties
Time
Designat
State
ed as Radon
EPA Test
Zone 1
Requireme
nt for
Initial
Testing
or Zone
Freque
ncy of Type of School
Re- Covered
Testing
Who New
May School
Conduc RRNC
t the Requirem
Testing ent
Mitigation
Requirement for
Radon Level ≤ 4
pCi/L
2 a
Connecti
87.5
cut
Florida
13.4
Illinois 100
Iowa 100
Minnesot
a
New
Jersey
6
Required
Required
b
Recomme
nd
Encourag
e
ND
Every 5
years
Within 12 Twice,
months of 5 years
occupancy apart
ND
Every 5
years
Yes No No Yes Yes Yes
Yes Yes No Yes No No
Yes No Yes Yes No No
ND ND Yes Yes No Yes No No
ND Yes No Yes Yes No Yes c
Yes No Yes Yes Yes No
100 Voluntary ND
85.7 Required ND
Every 5
years