image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
FINNISH EXPERIENCES IN RADON
PREVENTION IN NEW CONSTRUCTION AND
ENERGY SAVING CONSTRUCTIONS
Olli Holmgren, Hannu Arvela
STUK - Radiation and nuclear safety authority
Finland
Radon protection conference
Dresden, December 2–3, 2013

image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Outline
Introduction
Radon prevention in Finland
Used methods and technical details
Effect on radon concentrations
New construction techniques
Air tightness, ventilation strategies
and indoor radon
Summary
Dec 2, 2013
2
Olli Holmgren

image
image
image
image
image
image
image
image
image
image
image
image
image
image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Emergency Preparedness
Nuclear security
Joint services
Expert services
Regulation
Radiation
practices
regulation
Director General
Nuclear
reactor
regulation
Environmental
radiation
surveillance
Nuclear
waste and
material
regulation
Public Affairs
Regional offices
and laboratory
Olkiluoto
Loviisa
(Pyhäjoki)
Rovaniemi
STUK organisation
Staff number 358 (2012)
Person-years by sector (2012):

image
image
image
image
image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Radon research at STUK in 2013
Surveys of indoor radon in dwellings, radon mitigation in existing
buildings and prevention in new building
Aim: production of expert information for prevention of high indoor
radon concentrations
Utilised in the development of guidance and a national radon strategy
in cooperation with other authorities
Radon scientists:
Hannu Arvela
Heikki Reisbacka
Tuomas Valmari
Olli Holmgren
Radon measurement service: 5 persons
Päivi Kurttio
Head of Laboratory
Health Risks and Radon Safety
Dec 2, 2013
4
Olli Holmgren

image
image
image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
H.Arvela, Las Vegas
5
16.9.2008
People: 5.2 mil
Housing: 1.4 mil dwellings in houses, 1.1 mil apartments
Average radon level: 100 Bq/m
3
Soil: moraine, gravel, sand, clay
Climate:
Average temperature (1981-2010)
South
North
July
+18
o
C
+15
o
C
January
-4
o
C
-13
o
C
Annual
+6
o
C
0
o
C

image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Factors increasing indoor radon concentrations
Cold climate resulting high
negative pressure levels
Permeable soil types
Average
238
U 40 Bq/kg
Rather tight house envelopes
Rare airing through windows in
heating seasons
Way of construction of the base
floor and foundation
16.9.2008
6
H.Arvela, Las Vegas

image
image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
H.Arvela, Las Vegas
7
16.9.2008
Geography - gravel deposits - eskers
Landscape features were created by meltwater gravel deposit
Pispala esker, Tampere City,
Finland

image
image
image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
H.Arvela, Las Vegas
8
16.9.2008
Major esker formations in
Finland
Radon concentrations are
high esp. in wide areas in
the southern Finland.
Some eskers are “top radon
areas”.

image
image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Radon Atlas of Finland 2010
Based on 87 000 low-rise
residential houses measured
between 1980 and 7/2008
Measurement results collected in
a national radon data base
Almost all measurements in
Finland have been done by STUK
Currently 113 000 houses (8 %)
have been measured
In radon-prone regions, 10–18%
of houses have been measured
Measurement statistics of all
municipalities at
www.stuk.fi
24.1.2012 Stockholm
9
Olli Holmgren
Percentage
>200 Bq/m
3
>25 %
10–25 %
3–10 %
1–3 %
<1 %
<10 measurements
Indoor radon in low-rise
residential buildings

image
image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Foundation and base floor types and radon
Dec 2, 2013
10
Olli Holmgren
Slab on ground
Prevalence 2006: 64%
High radon levels (mean 96 Bq/m
3
)
Crawl-space, suspended floor
Prevalence 2006: 19%
Low radon levels (mean 44 Bq/m
3
)
Monolithic slab
Prevalence 2006: 1%
Low radon levels (mean 38 Bq/m
3
)
Semi-basement and basement
Prevalence 2006: 16%
High radon (mean 151 Bq/m
3
)

image
image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Entry routes
Slab on ground
Gap between foundation wall
and floor slab
Permeable lightweight aggregate
concrete blocks
Non-sealed pipe penetrations
Basement or semi-basement
Light-weight concrete blocks
and hollow-block walls in
contact with soil
Dec 2, 2013
11
Olli Holmgren

image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Olli Holmgren
Dec 2, 2013
Regulations, key changes
New guide for radon prevention in 2003
• Use of a strip of bitumen felt for sealing
• Installation of radon piping ( as already in the previous
1993 guide)
New building code for foundations in 2004
• In the design and construction work, radon risks at the
construction site shall be taken into account
• Radon-technical design documents are required by the
building authorities in municipalities
12

image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Guide for radon prevention
First guide in 1993
Installation of radon piping
Sealing with hot bitumen
Developed by Helsinki University of Technology
Funding: Ministry of environment and Ministry of Social Affairs and Health
New guide published in 2003
Result of a research project,
cooperation between universities, companies and STUK
Use of a strip of bitumen felt for sealing
Installation of radon piping
(as already in the previous 1996 guide)
Revised 2012
13
Olli Holmgren
Dec 2, 2013

image
image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Radon resistant new construction, guideline
Sealing of joint between slab and foundation wall,
and walls in contact with soil
Polyesther-
reinforced
bitumen felt
cast in direct
contact with
bitumen felt at
least 15 cm
Figures from Guide RT 81-11099
Dec 2, 2013
14
Olli Holmgren

image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Installation of the bitumen felt
15
Figures from Guide RT 38056 (Katepal Oy)
Dec 2, 2013
Olli Holmgren

image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Example of successful sealing work
Bitumen felt before casting of floor slab
Dec 2, 2013
16
Olli Holmgren

image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Radon resistant new construction, guideline
Installation of a passive piping system:
discharge open above roof
Network of perforated
drainage pipe installed
below the floor slab
If radon concentration
> 200 Bq/m
3
,
install a radon fan
Dec 2, 2013
17
Olli Holmgren

image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Installation of radon piping
Dec 2, 2013
18
Olli Holmgren
Figure from Guide RT 81-11099

image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Piping in a house with semi-basement
Dec 2, 2013
19
Olli Holmgren
Figures from Guide RT 81-11099

image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Multi-branch radon piping
Dec 2, 2013
20
Olli Holmgren
1. Suction pipe (perforated drainage pipe)
- end of the pipe closed
2. Collector pipe
3. Exhaust duct
Figures from Guide RT 81-11099

image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
New-construction survey 2009
Aim: study the effect of new regulations and guidance
Original sample 3000 dwellings, randomly chosen
Building permission given in 2006
Notice of removal before November 2008
(=> Houses completed in 2006 – 2009)
13% of dwellings in low-rise houses that received building permission in
2006 (single family houses, semi-detached houses, terraced houses)
Radon concentration measured in 1561 dwellings
Final participation rate 52 %
Two months measurements in March - May 2009
Average radon concentration 95 Bq/m
3
, median 58 Bq/m
3
Ref. Arvela H, Holmgren O, Reisbacka H. Radon prevention in new construction in
Finland: a nationwide sample survey in 2009.
Radiation Protection Dosimetry vol. 148, pp. 465-474, 2012 .
Dec 2, 2013
21
Olli Holmgren

image
image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Results, Foundation and radon
Lowest concentrations
Houses with crawl space, median 29 Bq/m
3
Houses with a monolithic floor slab, median 27 Bq/m
3
Highest concentrations
Houses with semi-basement and basement,
average 161 Bq/m
3
, median 97 Bq/m
3
Main reason: defective measures for radon prevention
in the block walls in contact with soil
Separate foundation wall and slab on ground
Remarkable progress in radon prevention,
average 97 Bq/m
3
, median 68 Bq/m
3
22
Olli Holmgren
Dec 2, 2013

image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Olli Holmgren
Results
• Preventive measures were taken
- in 92 % of houses in six provinces with highest radon
concentration (Area 1)
- in 38 % of houses elsewhere in the country (Area 2)
- in 54 % of houses, whole country
Radon concentrations and radon reduction compared with houses
completed in 2000-2005 (sample survey 2006)
23
New construction
survey (2009)
Sample survey
(2006)
Radon reduction
Area 1
125 (Bq/m
3
)
237 (Bq/m
3
)
47%
Area 2
83 (Bq/m
3
)
112 (Bq/m
3
)
26%
Whole country
95 (Bq/m
3
)
142 (Bq/m
3
)
33%
Dec 2, 2013

image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Olli Holmgren
Results
• Preventive measures were taken
- in 92 % of houses in six provinces with highest radon
concentration (Area 1)
- in 38 % of houses elsewhere in the country (Area 2)
- in 54 % of houses, whole country
•Percentage exceeding 200 Bq/m3 and 400 Bq/m3
- 200 Bq/m3 10.6%
sample survey (2006)
15.8%
- 400 Bq/m3 2.1%
3.8%
Dec 2, 2013
24

image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Olli Holmgren
Dec 2, 2013
Radon concentration grouped by construction year
Results of 1949 – 2005 are based on the nationwide sample survey 2006
(STUK-A242, Mäkeläinen et al. 2009).
The last bar (2006-2008) represents the results of the new construction study (2009).
25
Decreasing
trend

image
image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
NSFS 2011
24.8.2011
Regression lines are fitted
for houses
• without preventive
measures
• with passive radon piping
and sealing carried with a
strip of bitumen felt
Local reference data is based
on the STUK data base,
87.000 low-rise houses
Effect of preventive measures
Radon concentration in houses with slab-on-ground foundation
and local reference values.
26

image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Effect of preventive measures
Studied using regression analysis
comparison of houses with and without preventive measures
Radon reduction
passive radon piping and sealing with a strip of bitumen felt 57%
passive radon piping without sealing 41%
Ref. Arvela H, Holmgren O, Reisbacka H. Radon prevention in new construction in
Finland: a nationwide sample survey in 2009.
Radiation Protection Dosimetry vol. 148, pp. 465-474, 2012 .
Dec 2, 2013
27
Olli Holmgren

image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Challenges
Widespread and skilled implementation of preventive measures
throughout the country
Lightweight aggregate concrete block walls in contact with soil
Houses build on crushed rock
Sealing of pipe penetrations
As a summary, both sealing and passive piping are needed
Dec 2, 2013
28
Olli Holmgren

image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
New construction techniques
Low energy and passive house construction
Increased thermal insulation
High air-tightness of the house envelope
Mechanical supply and exhaust ventilation with heat recovery
Same goals for passive house construction and radon prevention
In general, these techniques reduce radon level
Ref.: RADPAR Deliverable 13/7. Radon and Energy Efficient Construction:
Assessment and Recommendations
(available online
web.jrc.ec.europa.eu/radpar
,
WP 6)
Recent Finnish study on air-tightness and indoor radon
Ref.: Arvela, H., Holmgren, O., Reisbacka, H. and Vinha, J.
Review of low-energy construction, air tightness, ventilation strategies and
indoor radon: results from Finnish houses and apartments.
Radiation Protection Dosimetry (2013); doi:10.1093/rpd/nct278.
Dec 2, 2013
29
Olli Holmgren

image
image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Pressure differences
30
Olli Holmgren
Dec 2, 2013
MECHANICAL
SUPPLY AND
EXHAUST
VENTILATION
Pressure differences are created by the stack effect and forced exhaust ventilation
Ref. Arvela et al. RPD 2013

image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Negative pressure draws soil air into the house
Even a small gap enables the flow
Air permeability of the ground affects to the flow
On rough soils, higher air flow
Rough fillings under the floor slab,
promote the leakages
Even a small air flow can increase the
radon concentration above the ref. level
31
27.10.2013 Holmgren
200 Bq/m
3
50 000 Bq/m
3
5 Bq/m
3
1 m
3
/h

image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Prevalence of ventilation strategies
Finnish low-rise residential buildings. Source: National random sample surveys.
32
Olli Holmgren
Dec 2, 2013
Ref. Arvela et al. RPD 2013

image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Ventilation strategy vs. indoor radon
Effect of the ventilation strategy on the indoor radon concentration of detached houses with
slab on ground based on measurements in 5312 houses (source: national radon database).
33
Olli Holmgren
Dec 2, 2013
Natural
Mechanical
exhaust
Mechanical
supply and
exhaust
Total
Number of houses (
1985–1994
)
1538
1438
2336
5312
Radon concentration, average Bq/m
3
348 (1.00)
332 (0.95)
256 (0.74)
303
Radon concentration, median Bq/m
3
237 (1.00)
233 (0.98)
178 (0.75)
208
Radon concentration, local reference
value, median, Bq/m
3
,
1)
138
153
154
150
Ratio of radon concentration to local
reference value, median
1.76 (1.00)
1.64 (0.93)
1.30 (0.74)
1.51
Regression factor
2)
2.38 +-0.05
2.20 +-0.05
1.70 +- 0.05 2.03
Relative radon concentration
compared with natural ventilation,
95% confidence limits
3)
1.00
0.92 +-0.14
0.71 +- 0.14
Ref. Arvela et al. RPD 2013

image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Distribution of the ACH
50
(n
50
) leakage factor
Newly built wooden-frame
detached houses
(1995–2005, n = 79)
Apartments with concrete
structures (2001–2003, n = 40)
34
Olli Holmgren
Dec 2, 2013
Ref. Arvela et al. RPD 2013

image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Air tightness measurements, ACH
50
(1/h)
Finnish detached houses with a wooden frame
35
Olli Holmgren
Dec 2, 2013
Year of construction
N
Mean
Range
1950–1980, Polvinen et al. 1983
61
7.0
2.2–17.8
1978–1982, Polvinen et al. 1983*
28
3.5
1.0–7.5
1979–1982, Metiäinen et al. 1986*
32
2.7
1.1–6.0
1979–1984, Vinha et al. 2005
7
5.2
2.1–7.3
1985–1999, Vinha et al. 2005
40
4.1
0.5–8.9
2000–2003, Vinha et al. 2005
55
3.6
0.6–7.2
2005–2011, Kauppinen et al. 2012
12
1.2
0.9–3.2
Ref. Arvela et al. RPD 2013
* Special emphasis was given to air tightness during construction

image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Calculated pressure difference vs. air tightness
36
Olli Holmgren
Dec 2, 2013
5 % lower supply air flow
10 %
20 %
100 %
Unbalance between supply
and exhaust air flows
Details in
Arvela et al.
RPD 2013
Ref. Arvela et al. RPD 2013

image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Summary, Radon prevention
New regulations in the building code in 2004 has increased
considerable the number of houses protected against radon
Reference level of 200 Bq/m
3
became mandatory
Local building authority requires radon prevention in the building
permission, especially in radon-prone areas
Detailed guideline for designing radon preventive measures
in new construction
Radon concentrations have reduced 33 % in whole Finland,
47 % in provinces of highest concentration
STUK recommendations in Finland
Radon prevention in all new buildings
All remedial actions should aim at radon levels
well below the reference level
Dec 2, 2013
37
Olli Holmgren

image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Summary, New construction techniques
Low energy and passive house construction
Increased thermal insulation
High air-tightness of the house envelope
Mechanical supply and exhaust ventilation with heat recovery
Same goals for passive house construction and radon prevention
In general, the new techniques reduce radon level
Recent Finnish study on air-tightness and indoor radon
Interaction of mechanical ventilation and high air-tightness increases
risk of enhanced negative pressures in dwellings
Challenge to efficient radon prevention (adequate sealing of base floor)
Guidelines for adjusting the ventilation may need revision
Dec 2, 2013
38
Olli Holmgren

image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
References
Arvela H, Holmgren O, Reisbacka H. Radon prevention in new construction in
Finland: a nationwide sample survey in 2009. Radiation Protection Dosimetry
2012 148: 465-474.
Arvela, H., Holmgren, O., Reisbacka, H. and Vinha, J. (2013) Review of low-
energy construction, air tightness, ventilation strategies and indoor radon:
results from Finnish houses and apartments. Radiation Protection Dosimetry
2013; doi:10.1093/rpd/nct278.
Valmari T, Mäkeläinen I, Reisbacka H, Arvela H. Radon Atlas of Finland 2010.
STUKA245. Helsinki: Radiation and Nuclear Safety Authority; 2010. (In Finnish,
Swedish and English)
RADPAR reports available online at
http://web.jrc.ec.europa.eu/radpar/index.cfm
Dec 2, 2013
39
Olli Holmgren

image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
References, continued
Arvela H. Indoor radon sources, remediation and prevention in new construction. In:
Proceedings – Third European IRPA Congress, 14 – 18 June 2010, Helsinki, Finland.
Helsinki: Nordic Society for Radiation Protection; 2011. R12. p. 2991 – 3013.
Mäkeläinen I, Valmari T, Reisbacka H, Kinnunen T, Arvela H. (2011) Indoor Radon and
Construction Practices of Finnish homes from 20th to 21st century. Proceedings of the
third European IRPA congress, 14-18 June 2010, Helsinki, Finland, pp 561-569.
STUK/NSFS, electronic publication 2011.
Arvela H, Mäkeläinen I, Reisbacka H. Radon policy in Finland, achievements and
challenges. In: The Natural Radiation Environment, 8th International Symposium
(NREVIII). 2007 Oct 7 – 12; Brazil. American Institute of Physics, AIP Conference
Proceedings 1034. Melville New York, 2008a. p. 435 – 437.
Arvela H, Reisbacka H. Indoor radon mitigation. STUK-A252. Helsinki: Radiation and
Nuclear Safety Authority; 2012. (In Finnish)
Arvela H, Reisbacka H. Indoor radon mitigation. STUK-A237. Helsinki: Radiation and
Nuclear Safety Authority; 2009. (In Swedish)
Dec 2, 2013
40
Olli Holmgren

image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Thank you for you attention!
Contact information:
Olli Holmgren
olli.holmgren(at)stuk.fi
www.stuk.fi
,
www.radon.fi
p. +358 9 759 88 555
Laippatie 4, P.O.Box 14
FI-00881 Helsinki
Finland
Dec 2, 2013
41
Olli Holmgren

image
image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Bitumen felt
Dec 2, 2013
42
Olli Holmgren
Stepped base floor – three strips of
bitumen felt welded together
Bitumen felt welded to the surface
of the foundation wall (concrete)
- two strips needed
Figures from Guide RT 81-11099

image
image
image
image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Sealing of pipe penetrations
In practice, the sealing is often forgotten,
although it would be fairly easy to do.
43
Olli Holmgren
Dec 2, 2013
Chasing pipe
Elastic sealing
compaund
Mineral wool
Electrical cable,
water pipe
Chasing pipe
Figures from Guide RT 81-11099

image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Dimensioning of the radon piping
Length of the
piping (m)
Diameter of
the pipe (mm)
<30
> 80
30 – 45
> 100
45 – 75
> 130
Length of the
collector pipe (m)
Diameter of
the pipe (mm)
<15
> 100
15 – 30
> 160
Dec 2, 2013
44
Olli Holmgren
Loop-type piping
Multi-branch piping
Length of the
suction pipe (m)
Diameter of
the pipe (mm)
<10
> 65
10 – 15
> 80
Dimensions are such that standard pipes
for drainage systems can be used

image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Organisations related to indoor radon in dwellings
Dec 2, 2013
45
Olli Holmgren
Non governmental organizations
Universities: research
Societies in the area of indoor air:
risk communication
Private companies: remediation and
prevention work, measurements
Successful radon policy requires
good cooperation between
governmental and local authorities
as well as expert organizations
Ministry of Social
Affairs and Health
Government
Ministry of
Environment
Local building authorities:
building permission and
inspection of new buildings
Building code
STUK
Local health authorities:
health related issues in
existing buildings

image
image
SÄTEILYTURVAKESKUS • STRÅLSÄKERHETSCENTRALEN
RADIATION AND NUCLEAR SAFETY AUTHORITY
Development of energy regulations
1969
1985
2003
2008
2010
Passive
house*
External wall
0.41...0.93
0.28
0.25
0.24
0.17
0.1
Base floor
0.35...0.47
0.36
0.25
0.19
0.16
0.08
Roof
0.35...0.47
0.22
0.16
0.15
0.09
0.07
Window
2.44...3.14
2.1
1.4
1.4
1.0
0.67
Door
0.7
1.4
1.4
1.0
46
Olli Holmgren
Dec 2, 2013
Upper limits for thermal transmittance, U (W/(m
2
K)) presented
in the National Building Code of Finland
*U-values of a passive house built in Finland fulfilling the international
passive house definition