ASTM C168-03

Standard Terminology Relating to Thermal Insulation

SCOPE
1.1 This standard provides definitions, symbols, units, and abbreviations of terms used in ASTM standards pertaining to thermal insulating materials, and to materials associated with them.

General Information

• Status: Historical
• Publication Date: 09-Apr-2003
• ICS: 01.040.91 - Construction materials and building (Vocabularies)
• ICS: 91.100.60 - Thermal and sound insulating materials
• Technical Committee: C16 - Thermal Insulation
• Drafting Committee: C16.94 - Terminology

Relations

• Replaces: ASTM C168-02 - Standard Terminology Relating to Thermal Insulation
• Effective Date: 10-Apr-2003
• Replaced By: ASTM C168-05 - Standard Terminology Relating to Thermal Insulation
• Effective Date: 01-Jun-2005
• Referred By: ASTM C1784-20 - Standard Test Method for Using a Heat Flow Meter Apparatus for Measuring Thermal Storage Properties of Phase Change Materials and Products
• Effective Date: 10-Apr-2003
• Referred By: ASTM C1497-16 - Standard Specification for Cellulosic Fiber Stabilized Thermal Insulation
• Effective Date: 10-Apr-2003
• Referred By: ASTM C1482-23 - Standard Specification for Polyimide Flexible Cellular Thermal and Sound Absorbing Insulation
• Effective Date: 10-Apr-2003
• Referred By: ASTM C1879-21 - Standard Practice for Installation of Aluminum and Stainless Steel Jacketing over Thermal Insulation on Pipe and Rigid Tubing
• Effective Date: 10-Apr-2003
• Referred By: ASTM C1224-22 - Standard Specification for Reflective Insulation for Building Applications
• Effective Date: 10-Apr-2003
• Referred By: ASTM C1630-19 - Standard Guide for Development of Coverage Charts for Loose-Fill Thermal Building Insulations
• Effective Date: 10-Apr-2003
• Referred By: ASTM F3319-20 - Standard Specification for Selection and Application of Field-Installed Cryogenic Pipe and Equipment Insulation Systems on Liquefied Natural Gas (LNG)-Fueled Ships
• Effective Date: 10-Apr-2003
• Referred By: ASTM C1558-19 - Standard Guide for Development of Standard Data Records for Computerization of Thermal Transmission Test Data for Thermal Insulation
• Effective Date: 10-Apr-2003
• Referred By: ASTM C1852-20 - Standard Guide for Product Selection/Delivery Systems for Aerosol Foam Sealants and Adhesives
• Effective Date: 10-Apr-2003
• Referred By: ASTM C687-18 - Standard Practice for Determination of Thermal Resistance of Loose-Fill Building Insulation
• Effective Date: 10-Apr-2003
• Referred By: ASTM C1155-95(2021) - Standard Practice for Determining Thermal Resistance of Building Envelope Components from the In-Situ Data
• Effective Date: 10-Apr-2003
• Referred By: ASTM E1423-21 - Standard Practice for Determining Steady State Thermal Transmittance of Fenestration Systems
• Effective Date: 10-Apr-2003
• Referred By: ASTM C411-19 - Standard Test Method for Hot-Surface Performance of High-Temperature Thermal Insulation
• Effective Date: 10-Apr-2003

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation:C168–03
Standard Terminology Relating to
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Thermal Insulation
This standard is issued under the fixed designation C 168; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
equipment related measurement errors induced due to measurement
1. Scope
attempts beyond an apparatus range or calibration.
1.1 This standard provides definitions, symbols, units, and
DISCUSSION—Useofthe“apparent”modifierwithsystem Corsystem
abbreviations of terms used in ASTM standards pertaining to
R measurements is not permitted.
thermal insulating materials, and to materials associated with
apparent thermal resistivity, r , n—a thermal resistivity
a
them.
assigned to a material that exhibits thermal transmission by
2. Referenced Documents
several modes of heat transfer resulting in property variation
with specimen thickness, or surface emittance. See resistiv-
2.1 ISO Standard:
ity, thermal.
ISO 7345 Thermal Insulation—Physical Quantities and
2
Definitions
DISCUSSION—Seeentirediscussionunder apparent thermal conduc-
tivity.
3. Terminology
batt, n—blanket insulation manufactured to dimensions as
3.1 Definitions:
required by a specific application.
absorptance, n—the ratio of the radiant flux absorbed by a
blackbody, n—the ideal, perfect emitter and absorber of
body to that incident upon it.
thermal radiation. It emits radiant energy at each wavelength
absorption, n—transformation of radiant energy to a different
at the maximum rate possible as a consequence of its
form of energy by interaction with matter.
temperature, and absorbs all incident radiance.
apparent thermal conductivity, l , k , n—a thermal con-
blanket, n—flexible insulation product, supplied rolled or flat.
a a
ductivity assigned to a material that exhibits thermal trans-
blanket insulation, n—a relatively flat and flexible insulation
mission by several modes of heat transfer resulting in
in coherent sheet form furnished in units of substantial area.
property variation with specimen thickness, or surface emit-
blanket insulation, metal mesh, n— blanket insulation cov-
tance. See conductivity, thermal.
ered by flexible metal-mesh facings attached on one or both
sides.
DISCUSSION—Thermal conductivity and resistivity are normally con-
block insulation, n—rigid insulation preformed into rectangu-
sidered to be intrinsic or specific properties of materials and, as such,
lar units.
should be independent of thickness. When nonconductive modes of
heat transfer are present within the specimen (radiation, free convec-
board insulation, n—semirigid insulation preformed into
tion) this may not be the case. To indicate the possible presence of this
rectangular units having a degree of suppleness particularly
phenomena (for example, thickness effect) the modifier “apparent” is
related to their geometrical dimensions.
used, as in apparent thermal conductivity.
calcium silicate, n—insulation composed principally of hy-
DISCUSSION—Test data using the “apparent” modifier must be quoted
drous calcium silicate, and which usually contains reinforc-
only for the conditions of the measurement. Values of thermal conduc-
ing fibers.
tance (material C) and thermal resistance (material R) calculated from
apparent thermal conductivity or resistivity, are valid only for the same cellular elastomeric, n—insulation composed principally of
conditions.
natural or synthetic elastomers, or both, processed to form a
DISCUSSION—Test data labeled with “apparent” shall not include any
flexible, semirigid, or rigid foam which has a predominantly
closed-cell structure.
cellular glass, n—insulation composed of glass processed to
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form a rigid foam having a predominantly closed-cell
This terminology is under the jurisdiction of ASTM Committee C16 on
Thermal Insulation and is the direct responsibility of Subcommittee C16.94 on
structure.
Terminology.
cellular polystyrene, n—insulation composed principally of
Current edition approved April 10, 2003. Published June 2003. Originally
polymerized styrene resin processed to form a rigid foam
approved in 1941. Last previous edition approved in 2002 as C 168 – 02.
2
having a predominantly closed-cell structure.
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C168–03
two apparatus/specimen geometries: flat-slab specimens with parallel
cellular polyurethane, n—insulation composed principally of
heat flux lines, or cylindrical specimens with
...