1、Designation: E 1827 96 (Reapproved 2007)Standard Test Methods forDetermining Airtightness of Buildings Using an OrificeBlower Door1This standard is issued under the fixed designation E 1827; the number immediately following the designation indicates the year oforiginal adoption or, in the case of re
2、vision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 These test methods describe two techniques for measur-ing air leakage rates through a building en
3、velope in buildingsthat may be configured to a single zone. Both techniques use anorifice blower door to induce pressure differences across thebuilding envelope and to measure those pressure differencesand the resulting airflows. The measurements of pressuredifferences and airflows are used to deter
4、mine airtightness andother leakage characteristics of the envelope.1.2 These test methods allow testing under depressurizationand pressurization.1.3 These test methods are applicable to small indoor-outdoor temperature differentials and low wind pressure con-ditions; the uncertainty in the measured
5、results increases withincreasing wind speeds and temperature differentials.1.4 These test methods do not measure air change rate undernormal conditions of weather and building operation. Tomeasure air change rate directly, use Test Methods E 741.1.5 The text of these test methods reference notes and
6、footnotes that provide explanatory material. These notes andfootnotes, excluding those in tables and figures, shall not beconsidered as requirements of the standard.1.6 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of th
7、e user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use. For specific hazardstatements see Section 7.2. Referenced Documents2.1 ASTM Standards:2E 456 Terminology Relating to Quality and StatisticsE 631 Term
8、inology of Building ConstructionsE 741 Test Method for Determining Air Change in a SingleZone by Means of a Tracer Gas DilutionE 779 Test Method for Determining Air Leakage Rate byFan PressurizationE 1186 Practices forAir Leakage Site Detection in BuildingEnvelopes and Air Barrier SystemsE 1258 Test
9、 Method for Airflow Calibration of Fan Pressur-ization Devices2.2 ISO International Standard:3ISO 9972 Thermal InsulationDetermination of BuildingAirtightnessFan Pressurization Method2.3 Other Standard:3ANSI/ASME PTC 19.1Part 1, Measurement Uncertainty,Instruments, and Apparatus3. Terminology3.1 Def
10、initionsRefer to Terminology E 456 for definitionsof accuracy, bias, precision, and uncertainty.3.1.1 ACH50, nthe ratio of the air leakage rate at 50 Pa(0.2 in. H2O), corrected for a standard air density, to thevolume of the test zone (1/h).3.1.2 air leakage rate, Qenv, nthe total volume of airpassi
11、ng through the test zone envelope per unit of time (m3/s,ft3/min).3.1.3 airtightness, nthe degree to which a test zoneenvelope resists the flow of air.NOTE 1ACH50, air leakage rate, and effective leakage area areexamples of measures of building airtightness.3.1.4 blower door, na fan pressurization d
12、evice incorpo-rating a controllable fan and instruments for airflow measure-ment and building pressure difference measurement thatmounts securely in a door or other opening.3.1.5 building pressure difference, P, nthe pressure differ-ence across the test zone envelope (Pa, in. H2O).3.1.6 fan airflow
13、rate, Qfan, nthe volume of airflowthrough the blower door per unit of time (m3/s, ft3/min).1These test methods are under the jurisdiction of ASTM Committee E06 onPerformance of Buildings and are the direct responsibility of Subcommittee E06.41on Air Leakage and Ventilation Performance.Current editio
14、n approved Aug. 1, 2007. Published August 2007. Originallyapproved in 1996. Last previous edition approved in 2002 as E 1827 96 (2002).2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume inf
15、ormation, refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959
16、, United States.3.1.7 nominal airflow rate, Qnom, nthe flow rate indicatedby the blower door using the manufacturers calibrationcoefficients (m3/s, ft3/min).3.1.8 orifice blower door, na blower door in whichairflow rate is determined by means of the pressure drop acrossan orifice or nozzle.3.1.9 pre
17、cision index of the average, nthe sample stan-dard deviation divided by the square root of the number ofsamples.33.1.10 pressure station, na specified induced change inthe building pressure difference from the initial zero-flowbuilding pressure difference (Pa, in. H2O).3.1.11 single zone, na space i
18、n which the pressure differ-ences between any two places, as indicated on a manometer,differ by no more than 2.5 Pa (0.01 in. H2O) during fanpressurization at a building pressure difference of 50 Pa (0.2 in.H2O) and by no more than 5 % of the highest building pressuredifference achieved.NOTE 2A mult
19、iroom space that is interconnected within itself withdoor-sized openings through any partitions or floors is likely to satisfy thiscriterion if the fan airflow rate is less than 3 m3/s (6 3 103ft3/min) and thetest zone envelope is not extremely leaky.3.1.12 test zone, na building or a portion of a b
20、uilding thatis configured as a single zone for the purpose of this standard.NOTE 3For detached dwellings, the test zone envelope normallycomprises the thermal envelope.3.1.13 test zone envelope, nthe barrier or series of barriersbetween a test zone and the outdoors.NOTE 4The user establishes the tes
21、t zone envelope at such places asbasements or neighboring rooms by choosing the level of resistance toairflow between the test zone and outdoors with such measures as openingor closing windows and doors to, from, and within the adjacent spaces.3.1.14 zero-flow building pressure difference, nthe natu
22、ralbuilding pressure difference measured when there is no flowthrough the blower door.3.2 SymbolsThe following is a summary of the principalsymbols used in these test methods:Alt = altitude at site, m (ft),C = flow coefficient at standard conditions, m3/s(Pan)ft3/min (in. H2On),4L = effective leakag
23、e area at standard conditions,m2(in.2),n = envelope flow exponent (dimensionless),P = building pressure difference (see 3.1.5),P1= average pressure, Psta, at the primary pres-sure station, Pa (in. H2O),P2= average pressure, Psta, at the secondary pres-sure station, Pa (in. H2O),Pref= the reference p
24、ressure differential across thebuilding envelope, Pa (in. H2O),Psta= station pressure, Pa (in. H2O),Ptest= test pressure, Pa (in. H2O),Pzero1= zero-airflow pressure before test, Pa (in.H2O),Pzero2= zero-airflow pressure after test, Pa (in. H2O),Qenv= the air leakage rate, m3/s (ft3/min),Qenv1= avera
25、ge air leakage rate, Qenv, at the primarypressure station, m3/s (ft3/min),Qenv2= average air leakage rate, Qenv, at the second-ary pressure station, m3/s (ft3/min),Qfan= fan airflow rate (see 3.1.6),Qnom= nominal airflow rate (see 3.1.7),T = temperature, C (F),t = value from a two-tailed student t t
26、able forthe 95 % confidence level,dn = measurement uncertainty of the envelopeflow exponent (dimensionless),Vzone= volume of the test zone, m3(ft3),dQenv= measurement uncertainty of the average airleakage rate, m3/s (ft3/min),dQ50= the measurement uncertainty of Q50,m3/s(ft3/min),dQbias= estimated b
27、ias of the flow rate, m3/s (ft3/min),dQbias1= estimated bias of the flow rate at the primarypressure station, m3/s (ft3/min),dQbias2= estimated bias of the flow rate at the second-ary pressure station, m3/s (ft3/min),dQprecision= precision index of the average measuredflow rate, m3/s (ft3/min),dQpre
28、c1= precision index of the average measuredflow rate at the primary pressure station,m3/s (ft3/min),dQprec2= precision index of the average measuredflow rate at the secondary pressure station,m3/s (ft3/min),dP = measurement uncertainty of the averagemeasured pressure differential across thebuilding
29、envelope, Pa (in. H2O),dPbias= estimated bias of the pressure differentialacross the building envelope, Pa (in. H2O),dPbias1= estimated bias of the pressure differentialacross the building envelope at the primarypressure station, Pa (in. H2O),dPbias2= estimated bias of the pressure differentialacros
30、s the building envelope at the second-ary pressure station, Pa (in. H2O),dPprecision= precision index of the average measuredpressure differential across the building en-velope, Pa (in. H2O),dPprec1= precision index of the average measuredpressure differential across the building en-velope at the pr
31、imary pressure station, Pa(in. H2O),dPprec2= precision index of the average measuredpressure differential across the building en-velope at the secondary pressure station, Pa(in. H2O),E 1827 96 (2007)2dVzone= measurement uncertainty of the zone vol-ume, m3(ft3), = dynamic viscosity, kg/ms (lbm/fthr),
32、r = air density, kg/m3(lbm/ft3), andrcal= air density at which the calibration valuesare valid, kg/m3(lbm/ft3).4. Summary of Test Methods4.1 Pressure versus FlowThese test methods consist ofmechanical depressurization or pressurization of a buildingzone during which measurements of fan airflow rates
33、 are madeat one or more pressure stations. The air leakage characteristicsof a building envelope are evaluated from the relationshipbetween the building pressure differences and the resultingairflow rates. Two alternative measurement and analysis pro-cedures are specified in this standard, the singl
34、e-point methodand the two-point method.4.1.1 Single-Point MethodThis method provides air leak-age estimates by making multiple flow measurements nearP1= 50 Pa (0.2 in. H2O) and assuming a building flowexponent of n = 0.65.4.1.2 Two-Point MethodThis method provides air leakageestimates by making mult
35、iple flow measurements near P1=50Pa (0.2 in. H2O) and near P2= 12.5 Pa (0.05 in. H2O) thatpermit estimates of the building flow coefficient and flowexponent.5. Significance and Use5.1 AirtightnessBuilding airtightness is one factor thataffects building air change rates under normal conditions ofweat
36、her and building operation. These air change rates accountfor a significant portion of the space-conditioning load andaffect occupant comfort, indoor air quality, and buildingdurability. These test methods produce results that characterizethe airtightness of the building envelope. These results can
37、beused to compare the relative airtightness of similar buildings,determine airtightness improvements from retrofit measuresapplied to an existing building, and predict air leakage. Use ofthis standard in conjunction Practice E 1186 permits theidentification of leakage sources and rates of leakage fr
38、omdifferent components of the same building envelope. These testmethods evolved from Test Method E 779 to apply to orificeblower doors.5.1.1 Applicability to Natural ConditionsPressures acrossbuilding envelopes under normal conditions of weather andbuilding operation vary substantially among various
39、 locationson the envelope and are generally much lower than thepressures during the test. Therefore, airtightness measurementsusing these test methods cannot be interpreted as directmeasurements of natural infiltration or air change rates thatwould occur under natural conditions. However, airtightne
40、ssmeasurements can be used to provide air leakage parametersfor models of natural infiltration. Such models can estimateaverage annual ventilation rates and the associated energycosts. Test Methods E 741 measure natural air exchange ratesusing tracer gas dilution techniques.5.1.2 Relation to Test Me
41、thod E 779These test methodsare specific adaptations of Test Method E 779 to orifice blowerdoors. For nonorifice blower doors or for buildings too large touse blower doors, use Test Method E 779.5.2 Single-Point MethodUse this method to provide airleakage estimates for assessing improvements in airt
42、ightness.5.3 Two-Point MethodUse this method to provide airleakage parameters for use as inputs to natural ventilationmodels. The two-point method uses more complex data analy-sis techniques and requires more accurate measurements(Tables X1.1 and X1.2) than the single-point method. It can beused to
43、estimate the building leakage characteristics at buildingpressure differences as low as 4 Pa (0.016 in. H2O). A varietyof reference pressures for building envelope leaks has beenused or suggested for characterizing building airtightness.These pressures include 4 Pa (0.016 in. H2O), 10 Pa (0.04 in.H2
44、O), 30 Pa (0.12 in. H2O), and 50 Pa (0.2 in. H2O). TheASHRAE Handbook of Fundamentals uses 4 Pa.5.4 Depressurization versus PressurizationDepending onthe goals of the test method, the user may choose depressur-ization or pressurization or both. This standard permits bothdepressurization and pressuri
45、zation measurements to compen-sate for asymmetric flow in the two directions. Depressuriza-tion is appropriate for testing the building envelope tightness toinclude the tightness of such items as backdraft dampers thatinhibit infiltration but open during a pressurization test. Com-bining the results
46、 of depressurization and pressurization mea-surements can minimize wind and stack-pressure effects oncalculating airtightness but may overestimate air leakage due tobackdraft dampers that open only under pressurization.5.5 Effects of Wind and Temperature DifferencesCalmwinds and moderate temperature
47、s during the test improveprecision and bias. Pressure gradients over the envelope causedby inside-outside temperature differences and wind cause biasin the measurement by changing the building pressure differ-ences over the test envelope from what would occur in theabsence of these factors. Wind als
48、o causes pressure fluctuationsthat affect measurement precision and cause the data to beautocorrelated.6. Apparatus6.1 Blower DoorAn orifice blower door (see Fig. 1).6.2 Measurement Precision and BiasAppendix X1 listsrecommended values for the precision and bias of the mea-surements of airflow, pres
49、sure difference, wind speed, andtemperature to obtain the precision and bias for test resultsdescribed in 11.2 for the single-point method and 11.3 for thetwo-point method.6.2.1 Fan with Controllable FlowThe fan shall havesufficient capacity to generate at least a 40 Pa (0.20 in. H2O)building pressure difference in the zone tested and be control-lable over a calibrated range sufficient to generate the buildingpressure differences required by this standard.NOTE 5For testing most single family houses, a range of airflowsfrom 0.1 to 3 m3/s
