Submitted by Maria.Kapsalaki on Wed, 06/18/2014 - 12:16
Bake-out with dilution ventilation is a potential technology that can shorten emission cycle of indoor VOCs and other hazardous gas, and then reduce indoor environment pollution brought forward by building materials. This technology based on characteristic that chemical substance of building materials is easier to emit under high temperature. This paper used numerical value method to compute TVOC removal amount under different operation conditions and concentration changes indoor during bake-out exhaust dilution process.
Submitted by Maria.Kapsalaki on Thu, 10/31/2013 - 22:50
This article is devoted to Indoor Air Quality (IAQ) in two low energy houses, with different frames (cast concrete (I-BB) and timber frame (I-OB)) built in platform INCAS of INES (National Institute of Solar Energy -in french: Institut National de l’Energie Solaire). In order to quantify pollutant emissions due to building materials and products, an experimental protocol consisted in stopping ventilation systems -”balanced ventilation”- of each house (a little before and during the measurement campaign), closing doors and windows, and not allowing occupant.
This paper present the results of a test programme to validate the Dutch pre-normative protocol NVN 5623 ‘Radioactivity measurements: Determination of the activity of gamma-ray emitting nuclides in a counting sample by means of semi-conductor gamma-spectr
In situ gamma spectroscopy is widely utilised to determine the outdoor gamma dose rate from the soiland to calculate the natural and artificial radionuclide concentration and their contribution to the doserate. The application of in situ gamma spectroscopy in indoor environments can not supplyquantitative information about activity concentration of radionuclides in buildings materials, but thistechnique can provide interesting information about building materials as radon source.
Possibilities for harmonising controls on the radioactivity of building materials within the EuropeanUnion are being discussed in the Working Party on Natural Radiation Sources established by theArticle 31 Group of Experts (Euratom Treaty). The Working Party is preparing a document to aid theArticle 31 Expert Group and the European Commission in considering possible recommendations andtechnical guidance to the Member States for the implementation of the new Basic Safety StandardsDirective concerning the radioactivity of building materials.
High radon concentrations indoors usually depend on the possibilities of radon penetration from thesurrounding soil into the buildings. Radon concentrations in dwellings up to 100 kBq/m were found insome special regions (i.e. Schneeberg/Saxony, Umhausen/Tyrol) where the soil shows a high uraniumcontent and additionally a fast radon transport in the soil is possible. To reduce the radon exposure ofthe inhabitants in these "radon prone areas" it is necessary to look for building and insulating materialswith low radon permeability.
High concentrations of natural radionuclides in building materials result in high dose rate indoorsdue to radon and thoron exhalation and the ?-rays emitted from them. Among the naturalradionuclides contained in building materials, most attention has been given to 226Ra due to 222Rnexhalation and the subsequent internal exposure. In external dose calculations due to buildingmaterials it is usually assumed that there exists radioactive equilibrium among the radionuclides ofboth the uranium and thorium series.
The Nuclear Engineering Section of the National Technical University of Athens undertook the organisation of a European building material radon exhalation rate intercomparison exercise in the framework of the European Research into Radon In Construction Concerted Action (ERRICCA). The intercomparison started in June 1998 and it was concluded in February 1999. Twenty participants from 13 countries took part. The exercise focused on the radon exhalation rate determination from a concrete slab, specially constructed to produce radon surface flux well below 10 mBqm-2s-1.
Several kinds of studies have been carried out concerning building materials.The granitic region can be considered as a significant part of the country. In recent years graniticmaterials are being used as ornements or integrated on the walls inside the houses, producing highindoor radon levels. Studies of different coverings for granitic materials were tested employing incolorpaintings in order to reduce the radon exhalation from such granitic stones, without modifying theirappearance.
Indoor radon concentrations were determined with the use of track-etched detectors and two monitors,both for radon and one for the decay products, in various regions of Greece. Until now, 1137 dwellings have been measured. Some factors, that influence the radon concentration in dwellings, are discussed in this paper. The factors, used in this analysis, were derived from the householders answers to the relevant questions about various physical features of the dwelling. Different statistical methods were used, as the unpaired t-test and the ANOVA method.