ASTM_D_6245_-_12.pdf

Designation:D624512Standard Guide forUsing Indoor Carbon Dioxide Concentrations to EvaluateIndoor Air Quality and Ventilation1This standard is issued under the fixed designation D6245;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 guide describes how measured values of indoorcarbon dioxide(CO2)concentrations can be used in evalua-tions of indoor air quality and building ventilation.1.2 This guide describes the determination of CO2genera-tion rates from people as a function of body size and level ofphysical activity.1.3 This guide describes the experimentally-determined re-lationship between CO2concentrations and the acceptability ofa space in terms of human body odor.1.4 This guide describes the following uses of indoor CO2concentrations to evaluate building ventilationmass balanceanalysis to determine the percent outdoor air intake at an airhandler,the tracer gas decay technique to estimate wholebuilding air change rates,and the constant injection tracer gastechnique at equilibrium to estimate whole building air changerates.1.5 This guide discusses the use of continuous monitoringof indoor and outdoor CO2concentrations as a means ofevaluating building ventilation and indoor air quality.1.6 This guide discusses some concentration measurementissues,but it does not include or recommend a method formeasuring CO2concentrations.1.7 This guide does not address the use of indoor CO2tocontrol outdoor air intake rates.1.8 UnitsThe values stated in SI units are to be regardedas standard.No other units of measurement are included in thisstandard.1.9 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D1356 Terminology Relating to Sampling and Analysis ofAtmospheresD3249 Practice for General Ambient Air Analyzer Proce-duresE741 Test Method for Determining Air Change in a SingleZone by Means of a Tracer Gas Dilution2.2 Other Documents:ASHRAE Standard 62.1 Ventilation for Acceptable IndoorAir Quality33.Terminology3.1 DefinitionsFor definitions and terms used in thisguide,refer to Terminology D1356.3.2 Definitions of Terms Specific to This Standard:3.2.1 air change rate,nthe total volume of air passingthrough a zone to and from the outdoors per unit time,dividedby the volume of the zone(s1,h1).43.2.2 bioeffluents,ngases emitted by people as a productof their metabolism that can result in unpleasant odors.3.2.3 single-zone,nan indoor space,or group of spaces,wherein the CO2concentration is uniform and that onlyexchanges air with the outdoors.4.Summary of Guide4.1 When investigating indoor air quality and buildingventilation,a number of tools are available.One such tool isthe measurement and interpretation of indoor and outdoor CO2concentrations.Using CO2concentrations to evaluate buildingindoor air quality and ventilation requires the proper use of theprocedures involved,as well as consideration of several factorsrelated to building and ventilation system configuration,occu-pancy patterns,non-occupant CO2sources,time and location1This guide is under the jurisdiction of ASTM Committee D22 on Air Qualityand is the direct responsibility of Subcommittee D22.05 on Indoor Air.Current edition approved April 1,2012.Published May 2012.Originallyapproved in 1998.Last previous edition approved in 2007 as D6245 07.DOI:10.1520/D6245-12.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Available from American Society of Heating,Refrigerating,and Air-Conditioning Engineers,Inc.,1791 Tullie Circle,NE,Atlanta,GA 30329.4Acommon way of expressing air change rate units is h-1=air changes per hour.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 of air sampling,and instrumentation for concentration mea-surement.This guide discusses ways in which CO2concentra-tions can be used to evaluate building indoor air quality andventilation.4.2 Section 6 discusses the rate at which people generateCO2and the factors that affect this rate.4.3 Section 7 discusses the use of indoor concentrations ofCO2as an indicator of the acceptability of a space in terms ofperceptions of human body odor.4.4 Section 8 describes the use of mass balance analysis todetermine the percent outdoor air intake at an air handler basedon the measured CO2concentrations in the supply,return,andoutdoor air intake airstreams.