ASTM E1445-08(2023)
(Terminology)Standard Terminology Relating to Hazard Potential of Chemicals
Standard Terminology Relating to Hazard Potential of Chemicals
SCOPE
1.1 This standard is a compilation of terminology used in the area of hazard potential of chemicals. Terms that are generally understood or adequately defined in other readily available sources are not included.
1.2 Although some of these definitions are general in nature, many must be used in the context of the standards in which they appear. The pertinent standard number is given in parentheses after the definition.
1.3 In the interest of common understanding and standardization, consistent word usage is encouraged to help eliminate the major barrier to effective technical communication.
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
General Information
Relations
Standards Content (Sample)
This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: E1445 − 08 (Reapproved 2023)
Standard Terminology Relating to
Hazard Potential of Chemicals
This standard is issued under the fixed designation E1445; 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 (´) indicates an editorial change since the last revision or reapproval.
1. Scope E659 Test Method for Autoignition Temperature of Chemi-
cals
1.1 This standard is a compilation of terminology used in
E680 Test Method for Drop Weight Impact Sensitivity of
the area of hazard potential of chemicals. Terms that are
Solid-Phase Hazardous Materials
generally understood or adequately defined in other readily
E681 Test Method for Concentration Limits of Flammability
available sources are not included.
of Chemicals (Vapors and Gases)
1.2 Although some of these definitions are general in nature,
E698 Test Method for Kinetic Parameters for Thermally
many must be used in the context of the standards in which
Unstable Materials Using Differential Scanning Calorim-
they appear. The pertinent standard number is given in paren-
etry and the Flynn/Wall/Ozawa Method
theses after the definition.
E771 Test Method for Spontaneous Heating Tendency of
1.3 In the interest of common understanding and Materials (Withdrawn 2001)
E918 Practice for Determining Limits of Flammability of
standardization, consistent word usage is encouraged to help
eliminate the major barrier to effective technical communica- Chemicals at Elevated Temperature and Pressure
E1226 Test Method for Explosibility of Dust Clouds
tion.
E1231 Practice for Calculation of Hazard Potential Figures
1.4 This international standard was developed in accor-
of Merit for Thermally Unstable Materials
dance with internationally recognized principles on standard-
E1232 Test Method for Temperature Limit of Flammability
ization established in the Decision on Principles for the
of Chemicals
Development of International Standards, Guides and Recom-
E1491 Test Method for Minimum Autoignition Temperature
mendations issued by the World Trade Organization Technical
of Dust Clouds
Barriers to Trade (TBT) Committee.
E1515 Test Method for Minimum Explosible Concentration
of Combustible Dusts
2. Referenced Documents
E1981 Guide for Assessing Thermal Stability of Materials
2.1 ASTM Standards:
by Methods of Accelerating Rate Calorimetry
E476 Test Method for Thermal Instability of Confined Con-
E2012 Guide for the Preparation of a Binary Chemical
densed Phase Systems (Confinement Test) (Withdrawn
Compatibility Chart
2008)
E2019 Test Method for Minimum Ignition Energy of a Dust
E487 Test Methods for Constant-Temperature Stability of
Cloud in Air
Chemical Materials
E2021 Test Method for Hot-Surface Ignition Temperature of
E537 Test Method for Thermal Stability of Chemicals by
Dust Layers
Differential Scanning Calorimetry
E2046 Test Method for Reaction Induction Time by Thermal
E582 Test Method for Minimum Ignition Energy and
Analysis
Quenching Distance in Gaseous Mixtures
3. Terminology
3.1 Definitions:
This terminology is under the jurisdiction of ASTM Committee E27 on Hazard
adiabatic calorimeter, n—an instrument capable of making
Potential of Chemicals and is the direct responsibility of Subcommittee E27.01 on
calorimetric measurements while maintaining a minimal
Editorial and Nomenclature.
heat loss or gain between the sample and its environment,
Current edition approved Nov. 15, 2023. Published December 2023. Originally
approved in 1991. Last previous edition approved in 2015 as E1445 – 08 (2015).
which is verifiable by the capability to continuously measure
DOI: 10.1520/E1445-08R23.
the temperature differential between the sample and its
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
surroundings. E1981
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
adiabatic decomposition temperature rise, (T) , n—an esti-
d
the ASTM website.
mation of the computed temperature which a specimen
The last approved version of this historical standard is referenced on
www.astm.org. would attain if all of the enthalpy (heat) of decomposition
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E1445 − 08 (2023)
1/3
reaction were to be absorbed by the sample itself. High K 5 dP/dt V
~ !
St
max
values represent high hazard potential. E1231
where:
anvil, n—the smooth, hardened surface upon which the test
P = pressure, (bar),
sample or cup containing the sample rests. E680
t = time, (s),
−E/RT V = volume, (m ), and
Arrhenius equation—k = Ze where k is the specific
K = (bar m/s).
St
reaction rate constant in reciprocal minutes for first order, Z
E1226
is the pre-exponential factor in reciprocal minutes, E is the
Arrhenius activation energy in J/mol, R is the gas constant,
differential scanning calorimetry (DSC), n—a technique in
8.32 J/mol K, and T is the temperature in kelvin. E698
which the difference in energy inputs into a substance and a
reference material is measured as a function of temperature,
autoignition, n—the ignition of a material commonly in air as
while the substance and the reference material are subjected
the result of heat liberation due to an exothermic oxidation
to a controlled temperature program. E698
reaction in the absence of an external ignition source such as
DISCUSSION—Two modes, power compensation differential scanning
a spark or flame. E659
calorimetry (power compensation DSC) and heatflux differential scan-
ning calorimetry (heatflux DSC), can be distinguished depending on the
autoignition temperature, n—the minimum temperature at
method of measurement used.
which autoignition occurs under the specified conditions of
test. E659
differential thermal analysis (DTA), n—a technique in which
DISCUSSION—Autoignition temperature is also referred to as sponta-
the temperature difference between a substance and refer-
neous ignition temperature, self-ignition temperature, autogenous igni-
ence material is measured as a function of temperature while
tion temperature, and by the acronyms AIT and SIT. AIT is the lowest
the substance and the reference material are subjected to a
temperature at which the substance will produce hot-flame ignition in
controlled temperature program. E698
air at atmospheric pressure without the aid of an external energy source
such as spark or flame. It is the lowest temperature to which a
(dP/dt) , n—the maximum rate of pressure rise during the
ex
combustible mixture must be raised, so that the rate of heat evolved by
course of a single deflagration. E1226
the exothermic oxidation reaction will over-balance the rate at which
heat is lost to the surroundings and cause ignition.
(dP/dt) , n—maximum value for the rate of pressure in-
max
crease per unit time reached during the course of a defla-
compatibility, adj—the ability of materials to exist in contact
gration for the optimum concentration of the dust tested. It is
without specified (usually hazardous) consequences under a
determined by a series of tests over a large range of
defined scenario. E2012
concentrations. It is reported in bar/s. E1226
constant-temperature stability (CTS) value, n—the maxi-
drop weight, n—that weight which is raised to a selected
mum temperature at which a chemical compound or mixture
height and released. This weight does not impact the sample
may be held for a 2-h period under the conditions of the test
directly; rather it strikes another stationary weight that is in
without exhibiting a measurable exothermic reaction. E487
contact with the sample. E680
cool-flame, n—a faint, pale blue luminescence or flame occur-
DTA (DSC) curve, n—a record of a thermal analysis where the
ring below the autoignition temperature (AIT). E659
temperature difference (ΔT) or the energy change (Δq) is
DISCUSSION—Cool-flames occur in rich vapor-air mixtures of most
hydrocarbons and oxygenated hydrocarbons. They are the first part of
plotted on the ordinate and temperature or time is plotted on
the multistage ignition process.
the abscissa (see Figs. 3 and 4). E537
critical half thickness, (a), n—an estimation of the half
dust concentration, n—the mass of dust divided by the
thickness of a sample in an unstirred container, in which the
internal volume of the test chamber. E1491
heat losses to the environment are less than the retained heat.
extrapolated onset temperature, n—empirically, the tempera-
This buildup of internal temperature leads to a thermal-
ture found by extrapolating the baseline (prior to the peak)
runaway reaction. E1231
and the leading side of the peak to their intersection (see Fig.
critical temperature, (T ), n—an estimation of the lowest
c
3). E537
temperature of an unstirred container at which the heat
final temperature (T ), n—the lowest temperature, cor-
final
losses to the environment are less than the retained heat
rected to a pressure of 101.3 kPa (760 mm Hg, 1013 mbar),
leading to a buildup of internal temperature. This tempera-
at which application of an ignition source causes the vapors
ture buildup leads to a thermal-runaway reaction. E1231
of the specimen to ignite under specified conditions of test.
DISCUSSION—This description assumes perfect heat removal at the
reaction boundary. This condition is not met if the reaction takes place E1232
in an insulated container such as when several containers are stacked
flash point, n—the observed system temperature at the end of
together or when a container is boxed for shipment. These figures-of-
an exotherm, generally at the temperature where the self-
merit underestimate the hazard as a result of this underestimation of
heat rate of the reaction has decreased below the operator-
thermal conductivity.
defined slope sensitivity threshold. (1981) E1232
deflagration index, (K ), n—maximum dP/dt normalized to a
St
3 n
1.0 m volume. It is measured at the optimum dust concen- general rate law—dC/dt = k(1 − C) where C is fractional
tration. K is defined according to the following cubic conversion, t is the time in minutes, and n is the reaction
St
relationship: order. E698
E1445 − 08 (202
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.