Laboratory measurements of electro-osmotic pulsing technology in reducing radon soil gas diffusion through a concrete slab

This paper presents the experimental results of utilizing Electro-Osmotic Pulsing Technology toreduce the diffusion of radon soil gas through a concrete slab. A laboratory system with state-of-theartinstrumentation has been used to measure the diffusion coefficient of radon soil gas through 30.5cm diameter, 10.2 cm thick standard composition concrete samples (w/c = 0.5 and cement:sand:gravel= 1:2:4). Within these concrete samples, a triple titanium anode configuration is embedded while anexternal copper rod is used as the cathode.

Laboratory assessment of flexible thin-film membranes as a passive barrier to radon gas diffusion

This paper presents the experimental results of utilizing a flexible thin-film membrane as a passivebarrier to radon gas diffusion. Nine commercially available membranes of various compositions andthicknesses were evaluated as retardant to radon gas diffusion. The radon gas concentration ratiosacross the thin-film membranes alone and in combination with an adjacent concrete sample (effectivediffusion coefficient) were measured in a laboratory system with state-of-the-art instrumentation.

Methods for measuring diffusion coefficients of radon in building materials

Two methods for determining the 222Rn diffusion coefficient in building materials are presented.Experimentally, the measurement of radon release rates under well-controlled conditions, using aflush and adsorption technique, underlies both methods. However, the theoretical principle of thetwo methods differs. The first method uses samples with a cubical or rectangular geometry andhas, as a prerequisite that a 100% radon tight surface covering method is available.

Radon concentrations affected by different factors in two office buildings

In the study, the factors affecting concentrations of radon vertically lines were surveyed in twolarge office buildings. Integrated concentrations of radon were determined with alpha track etchfilms (2 months) and continuous monitoring (2-6 days) was carried out with Pylon AB-5equipment. The effective air exchange rates were analysed by the tracer gas method with aninfrared analyser and rates of air flows from vents were measured with a thermoanemometer.Pressure differences were measured with a manometer and temperature differences withthermoelements.

Case study of a floor-integrated solution for heating and ventilation in a pre-cast concrete domestic building

The paper describes a system solution developed in Sweden for domestic buildings with pre-cast concrete units where the floor consists of a 0,06 meter thick concrete slab with a framework casted into the slab and a beam. The beams acts as floor beams forming a cavity of about 0,3 meter that are used for plumbing, electric installations and transport of air for heating and ventilation. The air is blown from the cavity into the rooms through narrow slots along the walls. Air for heating is recirculated through a ventilation plant consisting of filter, heating element and a fan.

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