Radon levels and indoor air quality after application of thermal retrofit measures - a case study

Abstract

This study was conducted toevaluate the influence of thermal retrofit on radon levels in workrooms,and to determine whetherthe radon concentrationin the building changes after the application of retrofit measures.In thefirst survey, digital radon detector Airthings Corentium Homewas usedfor one month radon measurementsduring heating season 2018/19.The dailyaveraged radon concentrationsvaried from 37-573 Bq/m3for ten selectedworkrooms, while hourly averaged radon measurements showed extreme variations from 6-1603 Bq/m3 due to radon fluctuations. In second survey, passive radon technique based on charcoal canister test kit was conducted in all basement workrooms in spring 2021.The averaged radon concentrations grouped according to flooring type in workrooms were: 327 Bq/m3 for parquet, 227 Bq/m3 for ceramic tiles, 146 Bq/m3 for vinyl flooring and 71 Bq/m3 for laminate. Besides thermal insulation and airtight windows, noticeable differences in indoor radon concentration within the renovated building are primarily caused by different types of flooring. It includes various types of insulation from the ground/concrete slab: laminate, parquet (wood blocks), vinyl flooring and ceramic tiles. Detailed analysis pointout that laminateismore efficient way for radon protection than other types of flooring.An efficient ventilation system should be installed to avoidincreasing occupational radon exposure and to provide healthy and comfortable indoor environment.