A. Poffijn (FANC/UGent)

Santander July 05

Radon exposure vs exposure to other sources of ionising radiation

Content• General distribution

• Man-made sources

• Natural sources

A. Poffijn (FANC/UGent)

Exposure from radiation sourcesGeneral

Source Belgium(mSv/y)

Worldwide(mSv/y)

Man-made 2,0 1,35

Natural 2,5 2,4

Total 4,5 3,75

A. Poffijn (FANC/UGent)

Exposure from radiation sourcesMan-made

Belgium(mSv/y)

Worldwide(mSv/y)

Medical 1,95 1,3

Other 0,05 0,05

A. Poffijn (FANC/UGent)

Medical exposure

Belgium(mSv/y)

Worldwide(mSv/y)

Radiology 1,78 1,2

Nuclear 0,17 0,08

A. Poffijn (FANC/UGent)

RadiologyX-ray diagnostics

• In Belgium: 1200 X-ray examinations per year per 1000 (Unscear: 920)

• Average effective dose: 1,78 mSv/y (Unscear: 1,2)

• CT: 0,96 mSv/y0

10

20

30

40

50

60

%

Type

Abdomen

Angiography

Chest

CT

GI-tract

Mammography

Spine

Other

A. Poffijn (FANC/UGent)

Exposure from radiation sourcesNaturalBelgium

(mSv/y)Worldwide

(mSv/y)

Cosmic 0,35 0,4

Externalterrestrial

0,4 0,5

Radon &Thoron

1,45 1,2

Other internalexposure

0,3 0,3

A. Poffijn (FANC/UGent)

Radon in the domestic environment (I)General

Arithmic mean(Bq/m3)

Range(Bq/m3)

Worldwide 46 5-20000

Spain 86 10-15400

Belgium 48 5-2000

A. Poffijn (FANC/UGent)

Radon in the domestic environment (II)Reference levels

New(Bq/m3)

Existing(Bq/m3)

ICRP 200-600 200-600WHO 200 200EU 200 400Spain 200 -Belgium 400 400All Europe 150-1000 150-1000

A. Poffijn (FANC/UGent)

Radon in the domestic environment (III)Sources (BE)

Source Reference value(Bq/m3)

Range(Bq/m3)

Soil 25 5-2000

Building mat. 15 5-100

Outdoor air 10 5-20

Water supply 0 0-10

TOTAL 50 15-2000

A. Poffijn (FANC/UGent)

Radon in the domestic environment (IV)

Risk mapping (BE)

• Indicative map (Rn-south > Rn-north)

• Radon survey in 10000 homes in Southern Belgium

• Geo-statistical analysis

• General risk map

SouthernBelgium

HauteArdenne

Arith. mean 80 Bq/m3 150 Bq/m3

< 100 70% 50%

100-199 24% 30%

200-399 5% 12%

400 & more 1% 8%

A. Poffijn (FANC/UGent)

Radon in Belgium.

Categories

Less than 1% above 200 Bq/m³

Less than 1% above 400 Bq/m³

1 à 5% above 400 Bq/m³

More than 5% above 400 Bq/m³

Antwerpen

Mechelen

Turnhout

Leuven

Nivelles (Br-W)

Brugge

IeperKortrijk

Oostende

Tielt

Veurne

Aalst

Eeklo

Gent

Oudenaarde

St Niklaas

Ath

CharleroiMons

Soignies

Thuin

Tournai

Huy

Liege

Verviers

Waremme

Hasselt

Maaseik

Tongeren

Bastogne

Marche

Neufchateau

Virton

Dinant

Namur

Philippeville

Roeselare

Diksmuide Dendermonde

Halle-Vilvoorde

Brussel

Arlon

Mouscron

A. Poffijn (FANC/UGent)

Radon at work (I)Reference levels

• Directive 96/29/Euratom

• Enhanced exposure to natural radiation cannot be neglected from R.P.

• Work activities Radon at work NORM Aviation exposure

ICRP 500-1500 Bq/m3

EU 500-1000 Bq/m3

Spain

Belgium 800 kBq/m3*h

Other Europeancountries

200-3000 Bq/m3

A. Poffijn (FANC/UGent)

Radon at work (II)Categories of workplaces (BE)

• All underground workplaces (mushroom galleries and visitor caves included)

• Facilities for water production, treatment and distribution

• Workplaces at ground level in radon risk areas as defined for homes

• Any other type of work place as defined by the FANC

A. Poffijn (FANC/UGent)

???

• General distribution of radiation burden:

What is the (best) way of presenting national data (population weighted ,...)

• Radon mapping :

What is the (best) way for presenting data in view of a combination at an international level? (average, geomean, percentage,…)