ASTM_E_1465_-_08a.pdf

Designation:E146508aStandard Practice forRadon Control Options for the Design and Construction ofNew Low-Rise Residential Buildings1This standard is issued under the fixed designation E1465;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This practice covers the design and construction of tworadon control options for use in new low-rise residentialbuildings.These unobtrusive(built-in)soil depressurizationoptions are installed with a pipe route appropriate for theirintended initial mode of operation,that is,fan-powered orpassive.One of these pipe routes should be installed during aresidential buildings initial construction.Specifications for thecritical gas-permeable layer,the radon systems piping,andradon entry pathway reduction are comprehensive and com-mon to both pipe routes.1.1.1 The first option has a pipe route appropriate for afan-powered radon reduction system.The radon fan should beinstalled after(1)an initial radon test result reveals unaccept-able radon concentrations and therefore a need for an operatingradon fan,or(2)the owner has specified an operating radonfan,as well as acceptable radon test results before occupancy.Fan operated soil depressurization radon systems reduce indoorradon concentrations up to 99%.1.1.2 The second option has a more efficient pipe routeappropriate for passively operated radon reduction systems.Passively operated radon reduction systems provide radonreductions of up to 50%.When the radon test results for abuilding with an operating passive system are not acceptable,that system should be converted to fan-powered operation.Radon systems with pipe routes installed for passive operationcan be converted easily to fan-powered operation;such fanoperated systems reduce indoor radon concentrations up to99%.1.2 The options provide different benefits:1.2.1 The option using the pipe route for fan-poweredoperation is intended for builders with customers who wantmaximum unobtrusive built-in radon reduction and docu-mented evidence of an effective radon reduction system beforea residential building is occupied.Radon systems with fan-powered type pipe routes allow the greatest architecturalfreedom for vent stack routing and fan location.1.2.2 The option using the pipe route for passive operationis intended for builders and their customers who want unob-trusive built-in radon reduction with the lowest possibleoperating cost,and documented evidence of acceptable radonsystem performance before occupancy.If a passive systemsradon reduction is unacceptable,its performance can be sig-nificantly increased by converting it to fan-powered operation.1.3 Fan-powered,soil depressurization,radon-reductiontechniques,such as those specified in this practice,have beenused successfully for slab-on-grade,basement,and crawlspacefoundations throughout the world.1.4 Radon in air testing is used to assure the effectiveness ofthese soil depressurization radon systems.The U.S.nationalgoal for indoor radon concentration,established by the U.S.Congress in the 1988 Indoor Radon Abatement Act,is toreduce indoor radon as close to the levels of outside air as ispracticable.The radon concentration in outside air is assumedto be 0.4 picocuries per litre(pCi/l)(15 Becquerels per cubicmetre(Bq/m3);the U.S.s average radon concentration inindoor air is 1.3 pCi/L(50 Bq/m3).The goal of this practice isto make available new residential buildings with indoor radonconcentrations below 2.0 pCi/L(75 Bq/m3)in occupiablespaces.1.5 This practice is intended to assist owners,designers,builders,building officials and others who design,manage,andinspect radon systems and their construction for new low-riseresidential buildings.1.6 This practice can be used as a model set of practices,which can be adopted or modified by state and localjurisdictions,to fulfill objectives of their residential buildingcodes and regulations.This practice also can be used as areference for the federal,state,and local health officials andradiation protection agencies.1.7 The new dwelling units covered by this practice havenever been occupied.Radon reduction for existing low riseresidential buildings is covered by Practice E2121,or by stateand local building codes and radiation protection regulations.1.8 Fan-powered soil depressurization,the principal strat-egy described in this practice,offers the most effective and1This practice is under the jurisdiction of ASTM Committee E06 on Perfor-mance of Buildings and is the direct responsibility of Subcommittee E06.41 on AirLeakage and Ventilation Performance.Current edition approved Dec.1,2008.Published January 2009.Originallyapproved in 1992.Last previous edition approved in 2008 as E1465 08.DOI:10.1520/E1465-08A.Copyright ASTM International,100 Barr Harbor D