1、Designation: C1153 10Standard Practice forLocation of Wet Insulation in Roofing Systems UsingInfrared Imaging1This standard is issued under the fixed designation C1153; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of la
2、st 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 applies to techniques that employ infraredimaging at night to determine the location of wet insulation inr
3、oofing systems that have insulation above the deck in contactwith the waterproofing. This practice includes ground-basedand aerial inspections. (WarningExtreme caution shall betaken when accessing or walking on roof surfaces and whenoperating aircraft at low altitudes, especially at night.)(WarningI
4、t is a good safety practice for at least two peopleto be present on the roof surface at all times when ground-based inspections are being conducted.)1.2 This practice addresses criteria for infrared equipmentsuch as minimum resolvable temperature difference, spectralrange, instantaneous field of vie
5、w, and field of view.1.3 This practice addresses meteorological conditions underwhich infrared inspections shall be performed.1.4 This practice addresses the effect of roof construction,material differences, and roof conditions on infrared inspec-tions.1.5 This practice addresses operating procedure
6、s, operatorqualifications, and operating practices.1.6 This practice also addresses verification of infrared datausing invasive test methods.1.7 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.8 This standard does not purport
7、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. Specific precau-tionary statements are given in 1
8、.1.2. Referenced Documents2.1 ASTM Standards:C168 Terminology Relating to Thermal InsulationD1079 Terminology Relating to Roofing and WaterproofingE1149 Definitions of Terms Relating to NDT by InfraredThermography2E1213 Test Method for Minimum Resolvable TemperatureDifference for Thermal Imaging Sys
9、tems2.2 ANSI-ASHRAE Standard:ANSI-ASHRAE Standard 101Application of InfraredSensing Devices to the Assessment of Building Heat LossCharacteristics32.3 ISO Standard:ISO/DP 6781.3EThermal InsulationQualitative Detec-tion of Thermal Irregularities in Building EnvelopesInfrared Method33. Terminology3.1
10、Definitions:3.1.1 blackbody, nthe ideal, perfect emitter and absorberof thermal radiation. It emits radiant energy at each wavelengthat the maximum rate possible as a consequence of its tempera-ture, and absorbs all incident radiance. (See TerminologyC168.)3.1.2 core, n, na small sample encompassing
11、 at least 13cm2of the roof surface area taken by cutting through the roofmembrane and insulation and removing the insulation todetermine its composition, condition, and moisture content.3.1.3 detection, nthe condition at which there is a consis-tent indication that a thermal difference is present on
12、 thesurface of the roof. Detection of thermal anomalies can beaccomplished when they are large enough and close enough tobe within the spatial resolution capabilities of the imagingsystem; that is, when their width is at least two times theproduct of the instantaneous field of view (IFOV) (see 3.1.8
13、)ofthe system and the distance from the system to the surface ofthe roof divided by 1000.3.1.4 emittance, , nthe ratio of the radiant flux emittedby a specimen to that emitted by a blackbody at the sametemperature and under the same conditions. (See TerminologyC168.)1This practice is under the juris
14、diction of ASTM Committee C16 on ThermalInsulation and is the direct responsibility of Subcommittee C16.30 on ThermalMeasurement.Current edition approved Sept. 1, 2010. Published October 2010. Originallyapproved in 1990. Last previous edition approved in 2003 as C1153 97(2003)1.DOI: 10.1520/C1153-10
15、.2Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.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 Consh
16、ohocken, PA 19428-2959, United States.3.1.5 expansion joint, na structural separation or flexibleconnection between two building elements that allows freemovement between the elements without damage to the roofingor waterproofing system. (See Terminology D1079.)3.1.6 field-of-view, (FOV), nthe total
17、 angular dimensions,expressed in radians, within which objects are imaged, dis-played and recorded by a stationary imaging device.3.1.7 infrared imaging system, nan apparatus that con-verts the spatial variations in infrared radiance from a surfaceinto a two-dimensional image, in which variations in
18、 radianceare displayed as a range of colors or tones.3.1.8 instantaneous field of view, (IFOV), nthe smallestangle, in milliradians, that will be instantaneously resolved bya particular infrared imaging system.3.1.9 membrane, na flexible or semiflexible roof coveringor waterproofing whose primary fu
19、nction is the exclusion ofwater. (See Terminology D1079.)3.1.10 minimum resolvable temperature difference (MRTD),na measure of the ability of operators of an infrared imagingsystem to discern temperature differences with that system. TheMRTD is the minimum temperature difference between a fourslot t
20、est pattern of defined shape and size and its blackbodybackground at which an average observer is capable ofdiscerning the pattern with that infrared imaging system at adefined distance.3.1.11 moisture meter probe, nan invasive (electricalresistance or galvanometric type) test that entails the inser
21、tionof a meter probe(s) through the roof membrane to indicate thepresence of moisture within the roofing system.3.1.12 radiance, nthe rate of radiant emission per unitsolid angle and per unit projected area of a source in a statedangular direction from the surface (usually the normal). (SeeTerminolo
22、gy C168.)3.1.13 recognition, nthe ability to differentiate betweendifferent types of thermal patterns such as board-stock, picture-framed and amorphous. Recognition of thermal anomalies isaccomplished when their width is at least eight times theproduct of the IFOV of the infrared imaging system and
23、thedistance from the system to the surface of the roof divided by1000.3.1.14 roof section, na portion of a roof that is separatedfrom adjacent portions by walls or expansion joints and inwhich there are no major changes in the components.3.1.15 roofing system, nan assembly of interacting com-ponents
24、 designed to weatherproof, and normally to insulate, abuildings top surface. (See Terminology D1079.)3.1.16 survey window, nthe time period during whichroof moisture surveys are successfully conducted according tothe requirements of Section 10.3.1.17 thermal anomaly, na thermal pattern of a surfacet
25、hat varies from a uniform color or tone when viewed with aninfrared imaging system. Wet insulation is capable of causingthermal anomalies.3.1.18 thermogram, na recorded visual image that mapsthe apparent temperature pattern of an object or scene into acorresponding contrast or color pattern. (See Te
26、rminologyE1149 with the word “recorded” added.)4. Significance and Use4.1 This practice is used to outline the minimum necessaryelements and conditions to obtain an accurate determination ofthe location of wet insulation in roofing systems using infraredimaging.4.2 This practice is not meant to be a
27、n instructional docu-ment or to provide all the knowledge and background neces-sary to provide an accurate analysis. For further information,see ANSI-ASHRAE Standard 101 and ISO/DP 6781.3E.4.3 This practice does not provide methods to determine thecause of moisture or its point of entry. It does not
28、 address thesuitability of any particular system to function capably aswaterproofing.5. Infrared Survey Techniques5.1 Ground-Based:5.1.1 Walk-OverWalking on a roof using an infraredimaging system. Imaging systems are hand-carried or mountedon a cart, is required. Thermograms are taken of areas ofint
29、erest. Areas that appear to contain wet insulation areidentified and marked for verification.5.1.2 Elevated Vantage PointUse of an infrared imagingsystem from an elevated vantage point provides an improvedview of the roof.5.2 Aerial:5.2.1 Real-Time ImagingUse of an infrared imaging sys-tem from an a
30、ircraft. Thermograms are obtained for the entireroof.6. Instrument Requirements6.1 General:6.1.1 ObjectiveInstrument requirements have been estab-lished in order to permit location of insulation that has lost aslittle as 20 % of its insulating ability because it containsmoisture.6.1.2 Spectral Range
31、The infrared imaging system shalloperate within a spectral range from 2 to 14 m. A spotradiometer or nonimaging line scanner is not sufficient.6.1.3 Minimum Resolvable Temperature Difference(MRTD)The MRTD at 20C shall be 0.3C.6.1.3.1 The survey shall be conducted with the thermalimaging system only
32、on sensitivity settings that meet thisrequirement.6.1.4 Test for Minimum Resolvable Temperature Difference:6.1.4.1 Instrument SettingThe thermal imaging systemshall be tested at each sensitivity that the system will be used.6.1.4.2 Test Target PatternThe test target shall consist oftwo plates with k
33、nown temperatures, located in front of theimaging system. The near plate shall have four equally spacedslots each having 7:1 height-to-width ratio (see Fig. 1).6.1.4.3 Test GeometryRefer to Fig. 1. The ratio of thewidth, (w), on the test pattern to the distance, (d), to theimaging system shall be es
34、tablished, using the maximum IFOVallowed for the type of survey being conducted, as follows:w/d , 0.002 IFOV!C1153 102where:w and d are in the same units and IFOV is in milliradians.Maximum allowable values of IFOV are defined in 6.2.2, 6.3.2,and 6.4.2.6.1.4.4 Test ProcedureIn accordance with Test M
35、ethodE1213, the temperature difference between the two plates ofthe target is slowly increased without communicating with theobserver. The observer announces when the test pattern comesinto view on the display. The temperature at this point isrecorded.6.1.4.5 Test ReplicatesBecause of differences in
36、 visualacuity, more than one observer shall perform the procedure in6.1.4.4. The average temperature difference is the MRTD forthat test condition.6.2 Walk-Over Surveys:6.2.1 Anomaly SizeInstrument requirements have beenestablished to permit recognition of areas of wet insulation assmall as 0.15 m o
37、n a side.6.2.2 Recognition Distance, FOV and IFOVRecognitionis accomplished when the width of a thermal anomaly, inmetres, is at least 0.008 times the product of the IFOV of thesystem and the distance, in metres, from the system to theanomaly. Since the walkover survey shall be accomplished at amaxi
38、mum distance of 5 m, the IFOV of the apparatus shall be3.8 milliradians, or less. The horizontal and vertical FOVs shallbe at least 0.21 rad by 0.10 rad, respectively.6.3 Elevated Vantage Point Surveys:6.3.1 Anomaly SizeInstrument requirements have beenestablished to permit recognition of areas of w
39、et insulation assmall as 0.15 m on a side.6.3.2 Recognition Distance, FOV and IFOVSince recog-nition must be possible at distances greater than 5 m, themaximum allowable IFOV in milliradians is related to dis-tance, (d), in metres from the infrared imaging system to theplace on the roof being scanne
40、d as follows:IFOV 5 18.8/dThe minimum horizontal FOV shall be 1.0/d and theminimum vertical FOV shall be 0.5/d, both expressed in rad.6.4 Aerial Surveys:6.4.1 Anomaly SizeAerial surveys shall be conductedwith infrared imaging systems that have the ability to detectareas of wet insulation as small as
41、 0.3 m on a side directlybelow the system.6.4.2 Detection Distance, FOV and IFOVDetection isaccomplished when the width of a thermal anomaly, in metres,is at least 0.002 times the product of the IFOV of the systemand the distance, in metres, from the system to the anomaly.The maximum allowable IFOV
42、is related to the verticaldistance (d), in metres, above the roof, as follows:IFOV 5 150/dThe FOV along the line of flight and across the line of flightshall be at least 0.05 rad by 0.10 rad, respectively. The usablefield of view shall be within 0.35 rad of a point directly belowthe infrared imaging
43、 system.7. Level of Knowledge7.1 The proper conduct of a roof moisture survey using aninfrared imaging system requires knowledge of how and underwhat circumstances the system is used and a general under-standing of roof construction.7.2 Proper interpretation of infrared data requires knowl-edge of i
44、nfrared theory, moisture migration, heat transfer,environmental effects, and roof construction as they apply toroof moisture analysis.8. Limitations (Applicability of Constructions)8.1 Applicable constructions include membrane systemscontaining any of the commercially available rigid insulationboard
45、s. This includes boards made of organic fibers, perlite,cork, fibrous glass, cellular glass, polystyrene, polyurethane,isocyanurate, and phenolic. Composite boards, tapered systemsmade from these materials and roofs insulated with foamed inplace polyurethane are able to be inspected.8.2 When extrude
46、d polystyrene insulation is placed underballast and above a protected membrane, it is quite difficult tolocate moisture in the insulation below the membrane by use ofinfrared thermography.8.3 Wet applied insulations such as lightweight concrete andwet applied decks such as gypsum are difficult to su
47、rvey sincethey are capable of retaining significant quantities of construc-tion water.8.4 When moisture sensitive materials are located underpavers, stone ballast or insulating gravel (for example, scoria),or layers of dry insulation, thermal anomalies on the surface ofthe roof are diminished.8.5 Fo
48、r roofs with highly reflective surfaces (that is, alumi-nized coatings or foils) in the spectral range of the infraredimaging system being used, infrared surveys are not practicaluntil the surface is naturally or temporarily dulled.8.6 The wetting rates of roof insulations vary according tothe type
49、of insulation and the environmental exposure. Allownew roofs with insulations that wet slowly, such as cellularplastics or cellular glass to dry at least eight months prior toconducting a survey.8.7 Infrared thermography is used to assist with locating wetroof insulation but will not always identify the source of themoisture.9. Significant Environmental Parameters9.1 Water retained in roofing systems decreases the thermalresistance and increases the heat storage capacity of suchFIG. 1 Test Arrangement for Minimum Resolvable TemperatureD
