hrvatski

SPECIFIČNA UKUPNA BETA AKTIVNOST LEBDEĆIH ČESTICA U ATMOSFERI ZAGREBA

Specific total β-activity As in Bqg-1 was investigated after the Fukushima accident in airborne particulate matter at two urban measuring sites in Zagreb. Sample aliquots were measured by means of beta counter for low-level activities (GM multi-counter system RISØ) five days after sampling in order to avoid the influence of short half-life radionuclides. Counter calibration was performed by 40K standard. At the traffic measuring site located in the southern part of the town PM2.5 particle fraction samples were collected at daily (noon to noon) basis using reference samplers LVS3 (Kleinfiltergerät, Sven Leckel Ingenieur Büro) following HRN EN 14907: 2006. At the traffic measuring site located closer to city centre daily (noon to noon) PM10 particle fraction samples were collected by means of high volume sampler DIGITEL DHA-80 following HRN EN 12341: 2006. After conditioning of filters and samples for constant air temperature and humidity (20±1 ºC ; 50±5 %) sample mass was determined using microbalance MX5 Mettler Toledo with resolution of 10-6 g for PM2.5 particle fraction or analytical balance AX205 Mettler Toledo with resolution of 10-5 g for PM10 particle fraction. Specific activity distributions are strictly separated into two groups, showing a significant rise of about 200 % when comparing the results obtained in the period 2011-2012 to the results from the period 2005-2007. This rise in specific activity could to be attributed to the Fukushima Dai-ichi nuclear accident, since no other accident of this level (7 at INES, The International Nuclear and Radiological Event Scale, IAEA) was reported during the last years.

ukupna beta aktivnost; specifična ukupna beta aktivnost; lebdeće čestice; PM10; PM2.5;

nije evidentirano

engleski

AIRBORNE PARTICULATES SPECIFIC TOTAL BETA AXCTIVITY IN ZAGREB ATMOSPHERE AFTER FUKUSHIMA ACCIDENT

Specific total β-activity As in Bqg-1 was investigated after the Fukushima accident in airborne particulate matter at two urban measuring sites in Zagreb. Sample aliquots were measured by means of beta counter for low-level activities (GM multi-counter system RISØ) five days after sampling in order to avoid the influence of short half-life radionuclides. Counter calibration was performed by 40K standard. At the traffic measuring site located in the southern part of the town PM2.5 particle fraction samples were collected at daily (noon to noon) basis using reference samplers LVS3 (Kleinfiltergerät, Sven Leckel Ingenieur Büro) following HRN EN 14907: 2006. At the traffic measuring site located closer to city centre daily (noon to noon) PM10 particle fraction samples were collected by means of high volume sampler DIGITEL DHA-80 following HRN EN 12341: 2006. After conditioning of filters and samples for constant air temperature and humidity (20±1 ºC ; 50±5 %) sample mass was determined using microbalance MX5 Mettler Toledo with resolution of 10-6 g for PM2.5 particle fraction or analytical balance AX205 Mettler Toledo with resolution of 10-5 g for PM10 particle fraction. Specific activity distributions are strictly separated into two groups, showing a significant rise of about 200 % when comparing the results obtained in the period 2011-2012 to the results from the period 2005-2007. This rise in specific activity could to be attributed to the Fukushima Dai-ichi nuclear accident, since no other accident of this level (7 at INES, The International Nuclear and Radiological Event Scale, IAEA) was reported during the last years.

na

nije evidentirano