ASTM C168-01

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-May-2001
• 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 C168-00 - Standard Terminology Relating to Thermal Insulating Materials
• Effective Date: 10-May-2001
• Replaced By: ASTM C168-02 - Standard Terminology Relating to Thermal Insulation
• Effective Date: 10-Jul-2002
• Referred By: ASTM F3340-22 - Standard Test Method for Thermal Resistance of Camping Mattresses Using a Guarded Hot Plate Apparatus
• Effective Date: 10-May-2001
• Referred By: ASTM C1224-22 - Standard Specification for Reflective Insulation for Building Applications
• Effective Date: 10-May-2001
• Referred By: ASTM E2988-17(2022) - Standard Practice for Specimen Preparation and Mounting of Flexible Fibrous Glass Insulation for Metal Buildings to Assess Surface Burning Characteristics
• Effective Date: 10-May-2001
• Referred By: ASTM C534/C534M-23 - Standard Specification for Preformed Flexible Elastomeric Cellular Thermal Insulation in Sheet and Tubular Form
• Effective Date: 10-May-2001
• Referred By: ASTM C1919-22 - Standard Practice for Measurement of the Steady-State Thermal Transmission Properties of Small Specimens Using the Heat Flow Meter Apparatus
• Effective Date: 10-May-2001
• Referred By: ASTM C1902-22a - Standard Specification for Cellular Glass Insulation Used in Building and Roof Applications
• Effective Date: 10-May-2001
• Referred By: ASTM C303-21 - Standard Test Method for Dimensions and Density of Preformed Block and Board–Type Thermal Insulation
• Effective Date: 10-May-2001
• Referred By: ASTM C1427-21 - Standard Specification for Extruded Preformed Flexible Cellular Polyolefin Thermal Insulation in Sheet and Tubular Form
• Effective Date: 10-May-2001
• Referred By: ASTM C755-20 - Standard Practice for Selection of Water Vapor Retarders for Thermal Insulation
• Effective Date: 10-May-2001
• Referred By: ASTM C1559-15(2021) - Standard Test Method for Determining Wicking of Fibrous Glass Blanket Insulation (Aircraft Type)
• Effective Date: 10-May-2001
• Referred By: ASTM C488-16(2023) - Standard Test Method for Conducting Exterior Exposure Tests of Finishes for Thermal Insulation
• Effective Date: 10-May-2001
• Referred By: ASTM C1071-19 - Standard Specification for Fibrous Glass Duct Lining Insulation (Thermal and Sound Absorbing Material)
• Effective Date: 10-May-2001
• Referred By: ASTM C516-19 - Standard Specification for Vermiculite Loose Fill Thermal Insulation
• Effective Date: 10-May-2001

Standards Content (Sample)

Designation: C 168 – 01
Standard Terminology Relating to
1
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.
DISCUSSION—Useofthe“apparent”modifierwithsystem Corsystem
1. Scope
R measurements is not permitted.
1.1 This standard provides definitions, symbols, units, and
abbreviations of terms used in ASTM standards pertaining to apparent thermal resistivity, r , n—a thermal resistivity
a
thermal insulating materials, and to materials associated with assigned to a material that exhibits thermal transmission by
them. several modes of heat transfer resulting in property variation
with specimen thickness, or surface emittance. See resistiv-
2. Referenced Documents
ity, thermal.
2.1 ISO Standard:
DISCUSSION—Seeentirediscussionunder apparent thermal conduc-
ISO 7345 Thermal Insulation—Physical Quantities and
tivity.
2
Definitions
blackbody, n—the ideal, perfect emitter and absorber of
3. Terminology
thermal radiation. It emits radiant energy at each wavelength
at the maximum rate possible as a consequence of its
3.1 Definitions:
temperature, and absorbs all incident radiance.
absorptance, n—the ratio of the radiant flux absorbed by a
blanket insulation, n—a relatively flat and flexible insulation
body to that incident upon it.
in coherent sheet form furnished in units of substantial area.
absorption, n—transformation of radiant energy to a different
blanket insulation, metal mesh, n— blanket insulation cov-
form of energy by interaction with matter.
ered by flexible metal-mesh facings attached on one or both
apparent thermal conductivity, l , k , n—a thermal con-
a a
sides.
ductivity assigned to a material that exhibits thermal trans-
block insulation, n—rigid insulation preformed into rectangu-
mission by several modes of heat transfer resulting in
lar units.
property variation with specimen thickness, or surface emit-
board insulation, n—semirigid insulation preformed into
tance. See conductivity, thermal.
rectangular units having a degree of suppleness particularly
related to their geometrical dimensions.
DISCUSSION—Thermal conductivity and resistivity are normally con-
sidered to be intrinsic or specific properties of materials and, as such,
calcium silicate, n—insulation composed principally of hy-
should be independent of thickness. When nonconductive modes of
drous calcium silicate, and which usually contains reinforc-
heat transfer are present within the specimen (radiation, free convec-
ing fibers.
tion) this may not be the case. To indicate the possible presence of this
cellular elastomeric, n—insulation composed principally of
phenomena (for example, thickness effect) the modifier “apparent” is
natural or synthetic elastomers, or both, processed to form a
used, as in apparent thermal conductivity.
flexible, semirigid, or rigid foam which has a predominantly
DISCUSSION—Test data using the “apparent” modifier must be quoted
only for the conditions of the measurement. Values of thermal conduc- closed-cell structure.
tance (material C) and thermal resistance (material R) calculated from
cellular glass, n—insulation composed of glass processed to
apparent thermal conductivity or resistivity, are valid only for the same
form a rigid foam having a predominantly closed-cell
conditions.
structure.
DISCUSSION—Test data labeled with “apparent” shall not include any
cellular polystyrene, n—insulation composed principally of
equipment related measurement errors induced due to measurement
polymerized styrene resin processed to form a rigid foam
attempts beyond an apparatus range or calibration.
having a predominantly closed-cell structure.
cellular polyurethane, n—insulation composed principally of
1
This terminology is under the jurisdiction of ASTM Committee C16 on
the catalyzed reaction product of polyisocyanate and poly-
Thermal Insulation and is the direct responsibility of Subcommittee C16.94 on
hydroxy compounds, processed usually with fluorocarbon
Terminology.
gas to form a rigid foam having a predominantly closed-cell
Current edition approved May 10, 2001. Published July 2001. Originally
structure.
published as C 168 – 41 T. Last previous edition C 168 – 00.
2
Available from American National Standards Institute, 11 W. 42nd St., 13th
Floor, New York, NY 10036.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
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C 168
Q L
cellulosic fiber, n—insulation composed principally of cellu-
Flat2slab geometryl5 (1)
A DT
lose fibers usually derived from paper, paperboard stock, or
wood, with or without binders.
cement, finishing, n—a mixture of dry fibrous or powdery
where:
materials, or b
...