ASTM E1995-21

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: E1995 − 21 An American National Standard
Standard Test Method for
Measurement of Smoke Obscuration Using a Conical
Radiant Source in a Single Closed Chamber, With the Test
Specimen Oriented Horizontally
This standard is issued under the fixed designation E1995; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope* flame under controlled conditions, but does not by itself
incorporate all factors required for fire hazard or fire risk
1.1 This is a fire-test-response standard.
assessment of the materials, products, or assemblies under
1.2 This test method provides a means of measuring smoke
actual fire conditions.
obscuration resulting from subjecting essentially flat materials,
1.9 Fire testing of products and materials is inherently
products, or assemblies (including surface finishes), not ex-
hazardous,andadequatesafeguardsforpersonnelandproperty
ceeding 25 mm (1 in.) in thickness, in a horizontal orientation,
shall be employed in conducting these tests. This test method
exposed to specified levels of thermal irradiance, from a
may involve hazardous materials, operations, and equipment.
conical heater, in the presence of a pilot flame, in a single
See also 6.2.1.2, Section 7, and 11.7.2.
closed chamber. Optional testing modes exclude the pilot
1.10 This standard does not purport to address all of the
flame.
NOTE 1—The equipment used for this test method is technically safety concerns, if any, associated with its use. It is the
equivalent to that used in ISO 5659-2 and in NFPA 270.
responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter-
1.3 The principal fire-test-response characteristic obtained
mine the applicability of regulatory limitations prior to use.
from this test method is the specific optical density of smoke
1.11 This international standard was developed in accor-
from the specimens tested, which is obtained as a function of
dance with internationally recognized principles on standard-
time, for a period of 10 min.
ization established in the Decision on Principles for the
1.4 An optional fire-test-response characteristic measurable
Development of International Standards, Guides and Recom-
with this test method is the mass optical density (see Annex
mendations issued by the World Trade Organization Technical
A1), which is the specific optical density of smoke divided by
Barriers to Trade (TBT) Committee.
the mass lost by the specimens during the test.
1.5 The fire-test-response characteristics obtained from this
2. Referenced Documents
test are specific to the specimen tested, in the form and
2.1 ASTM Standards:
thickness tested, and are not an inherent property of the
C1186Specification for Flat Fiber-Cement Sheets
material, product, or assembly.
C1288Specification for Fiber-Cement Interior Substrate
1.6 This test method does not provide information on the
Sheets
fire performance of the test specimens under fire conditions
D2843Test Method for Density of Smoke from the Burning
other than those conditions specified in this test method. For
or Decomposition of Plastics
limitations of this test method, see 5.5.
D4100 Test Method for Gravimetric Determination of
SmokeParticulatesfromCombustionOfPlasticMaterials
1.7 Use the SI system of units in referee decisions; see
(Withdrawn 1997)
IEEE/ASTMSI-10.Theinch-poundunitsgiveninparentheses
D5424Test Method for Smoke Obscuration of Insulating
are for information only.
Materials Contained in Electrical or Optical Fiber Cables
1.8 This test method is used to measure and describe the
When Burning in a Vertical Cable Tray Configuration
response of materials, products, or assemblies to heat and
1 2
This test method is under the jurisdiction of ASTM Committee E05 on Fire For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Standards and is the direct responsibility of Subcommittee E05.21 on Smoke and contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Combustion Products. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved June 1, 2021. Published June 2021. Originally the ASTM website.
approved in 1998. Last previous edition approved in 2018 as E1995–18. DOI: The last approved version of this historical standard is referenced on
10.1520/E1995-21. www.astm.org.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E1995 − 21
E84Test Method for Surface Burning Characteristics of 3.2.3 essentially flat surface, n—surface where the irregu-
Building Materials larity from a plane does not exceed 61 mm.
E176Terminology of Fire Standards
3.2.4 exposed surface, n—that surface of the specimen
E603Guide for Room Fire Experiments
subjected to the incident heat.
E662Test Method for Specific Optical Density of Smoke
3.2.5 flaming mode, n—the mode of testing that uses a pilot
Generated by Solid Materials
flame.
E906Test Method for Heat and Visible Smoke Release
3.2.6 ignition, n—the initiation of combustion.
Rates for Materials and Products Using a Thermopile
3.2.6.1 Discussion—The combustion may be evidenced by
Method
glow, flame, detonation, or explosion. The combustion may be
E1354Test Method for Heat and Visible Smoke Release
sustained or transient.
Rates for Materials and Products Using an Oxygen Con-
sumption Calorimeter 3.2.7 mass optical density, n—theratiooftheopticaldensity
E1474Test Method for Determining the Heat Release Rate
of smoke and the mass loss of the test specimen, multiplied by
of Upholstered Furniture and Mattress Components or thevolumeofthetestchamberanddividedbythelengthofthe
Composites Using a Bench Scale Oxygen Consumption light path.
Calorimeter
3.2.7.1 Discussion—Themassopticaldensityasdetermined
E1537Test Method for Fire Testing of Upholstered Furni- in this test method is not an intrinsic material property; it is a
ture
function of the test procedure and conditions used.
E1590Test Method for Fire Testing of Mattresses
3.2.8 Nonflaming mode, n—the mode of testing that does
IEEE/ASTM SI-10Practice for Use of the International
not use a pilot flame.
System of Units (SI): The Modernized Metric System
3.2.9 sample, n—an amount of the material, product, or
2.2 ANSI/AHA Standard:
assembly, to be tested, which is representative of the item as a
A135.4Basic Hardboard
whole.
2.3 ISO Standards:
3.2.10 smoke obscuration, n—thereductioninvisibilitydue
ISO Guide 52—Glossary of Fire Terms and Definitions
to smoke (ISO Guide 52).
ISO 3261Fire Tests–Vocabulary
ISO 5659-2Determination of Specific Optical Density by a 3.2.11 specimen, n—the actual section of material, product,
or assembly, to be placed in the test apparatus.
Single-Chamber Test
ISO 5725Precision of Test Methods—Determination of
3.2.12 time to ignition, n—time between the start of the test
Repeatability and Reproducibility for Standard Test
and the presence of a flame on the specimen surface for a
Method by Interlaboratory Tests
period of at least 4s.
2.4 British Standards:
4. Summary of Test Method
BS 6809Method of Calibration of Radiometers for Use in
Fire Testing
4.1 This test method assesses the reduction of light by
2.5 NFPA Standards:
smoke obscuration from a burning sample. The test method
NFPA270StandardTestMethodforMeasurementofSmoke
employsaconically-shaped,electrically-heated,radiant-energy
Obscuration Using a Conical Radiant Source in a Single
source to produce irradiance levels of 25 and 50 kW/m ,
Closed Chamber
averaged over the center of the exposed surface of an essen-
tially flat specimen, and mounted horizontally inside a closed
3. Terminology
chamber. The equipment is suitable for testing at irradiance
3.1 Definitions—For definitions of terms used in this test
levels of up to 50 kW/m .
method, refer to Terminology E176 and ISO3261. In case of
4.2 Thespecimenis75by75mm(3by3in.),atathickness
conflict, the definitions given in Terminology E176 shall
not exceeding 25 mm (1 in.) and is mounted horizontally
prevail.
within a holder.
3.2 Definitions of Terms Specific to This Standard:
4.3 The exposure is conducted in the presence or in the
3.2.1 assembly, n—a unit or structure composed of a com-
absence of a pilot flame (see details in 6.3.6). If a pilot flame
bination of materials or products, or both.
is used for ignition, the test is deemed to be in the “flaming”
3.2.2 continuous (as related to data acquisition), adj—
mode;ifapilotflameisnotused,thetestisdeemedtobeinthe
conducted at data collection intervals of 5s or less.
“nonflaming” mode.
4.4 The test specimens are exposed to flaming or nonflam-
ing conditions within a closed chamber.Aphotometric system
Available from American Hardboard Association, 1210 West Northwest
Highway, Palatine, IL 60067, United States.
with a vertical light path is used to measure the varying light
Available from International Standardization Organization, P.O. Box 56,
transmission as smoke accumulates. The light transmittance
CH-1211; Geneva 20, Switzerland, or from American National Standards Institute
measurements are used to calculate the specific optical density
(ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036.
Available from British Standards Institute (BSI), 389 Chiswick High Rd., of the smoke generated during the test.
London W4 4AL, U.K.
4.5 Thespecimensareexposedtotwoconditions,outofthe
Available from National Fire Protection Association (NFPA), 1 Batterymarch
Park, Quincy, MA 02169-7471, http://www.nfpa.org. four standard exposure conditions, to be chosen by the test
E1995 − 21
requester. The four standard exposure conditions are: flaming the flaming mode; molten material overflowing the specimen
mode at an irradiance of 25 kW/m , flaming mode at an holder; or, self-ignition in the nonflaming mode.
irradiance of 50 kW/m ; nonflaming mode at an irradiance of 5.5.2 As is usual in small-scale test methods, results ob-
25 kW/m ; and, nonflaming mode at an irradiance of 50 tained from this test method have proven to be affected by
kW/m . Unless specified otherwise, conduct testing in the two variationsinspecimengeometry,surfaceorientation,thickness
flaming mode exposure conditions (see 8.3, X1.3 and X1.4). (either overall or individual layer), mass, and composition.
Exposures to other irradiances also are possible. 5.5.3 The results of the test apply only to the thickness of
thespecimenastested.Nosimplemathematicalformulaexists
4.6 Mass optical density is an optional fire-test-response
to calculate the specific optical density of a specimen at a
characteristicobtainable from this test method, by usingaload
specimenthicknessdifferentfromthethicknessatwhichitwas
cell, which continuously monitors the mass of the test speci-
tested. The literature contains some information on a relation-
men (see Annex A1).
ship between optical density and specimen thickness (1).
5.5.4 Results obtained from this test method are affected by
5. Significance and Use
variations in the position of the specimen and radiometer
5.1 This test method provides a means for determining the
relativetotheradiantheatsource,sincetherelativepositioning
specificopticaldensityofthesmokegeneratedbyspecimensof
affects the radiant heat flux (see also Appendix X2).
materials,products,orassembliesunderthespecifiedexposure
5.5.5 The test results have proven sensitive to excessive
conditions. Values determined by this test are specific to the
accumulations of residue in the chamber, which serve as
specimen in the form and thickness tested and are not inherent
additional insulators, tending to reduce normally expected
fundamental properties of the material, product, or assembly
condensation of the aerosol, thereby raising the measured
tested.
specific optical density (see 5.5.8.3 and 11.1.2).
5.2 This test method uses a photometric scale to measure 5.5.6 The measurements obtained have also proven sensi-
smokeobscuration,whichissimilartotheopticaldensityscale
tive to differences in conditioning (see Section 10). Many
for human vision. The test method does not measure physi- materials, products, or assemblies, such as some carpeting,
ological aspects associated with vision.
wood, plastics, or textiles, require long periods to attain
equilibrium(constantweight)eveninaforced-draftcondition-
5.3 At the present time no basis exists for predicting the
ing chamber. This sensitivity reflects the inherent natural
smoke obscuration to be generated by the specimens upon
variability of the sample and is not specific to the test method.
exposure to heat or flame under any fire conditions other than
5.5.7 In this procedure, the specimens are subjected to one
those specified. Moreover, as with many smoke obscuration
or more specific sets of laboratory test conditions. If different
test methods, the correlation with measurements by other test
test conditions are substituted or the end-use conditions are
methods has not been established.
changed, it is not necessarily possible by or from this test
5.4 The current smoke density chamber test, Test Method
method to predict changes in the fire-test-response character-
E662, is used by specifiers of floor coverings and in the rail
istics measured; therefore, the results are valid only for the fire
transportation industries. The measurement of smoke obscura-
test exposure conditions described in this procedure.
tionisimportanttotheresearcherandtheproductdevelopment
5.5.8 This test method solves some limitations associated
scientist. This test method, which incorporates improvements
with other closed chamber test methods, such as Test Method
over Test Method E662, also will increase the usefulness of
E662(2-6)(see5.4.1).Thetestmethodretainssomelimitations
smoke obscuration measurements to the specifier and to
related to closed chamber tests, as detailed in 5.5.8.1 – 5.5.8.5.
product manufacturers.
5.5.8.1 Information relating the specific optical density
5.4.1 The following are improvements offered by this test
obtained by this test method to the mass lost by the specimen
method over Test Method E662: the horizontal specimen
duringthetestispossibleonlybyusingthe(optional)loadcell,
orientation solves the problem of melting and flaming drips
to determine the mass optical density (see Annex A1).
from vertically oriented specimens; the conical heat source
5.5.8.2 All specimens consume oxygen when combusted.
provides a more uniform heat input; the heat input can be
The smoke generation of some specimens (especially those
varied over a range of up to 50 kW/m , rather than having a
undergoing rapid combustion and those which are heavy and
fixed value of 25 kW/m ; and, the (optional) load cell permits
multilayered) is influenced by the oxygen concentration in the
calculations to be made of mass optical density, which associ-
chamber. Thus, if the atmosphere inside the chamber becomes
ates the smoke obscuration fire-test-response characteristic
oxygen-deficientbeforetheendoftheexperiment,combustion
measured with the mass loss.
may ceases for some specimens; therefore, it is possible that
5.5 Limitations : those layers furthest away from the radiant source will not
5.5.1 The following behavior during a test renders that test undergo combustion.
invalid:aspecimenbeingdisplacedfromthezoneofcontrolled 5.5.8.3 The presence of walls causes losses through depo-
sition of combustion particulates.
irradiance so as to touch the pilot burner or the pilot flame;
extinctionofthepilotflame(evenforashortperiodoftime)in 5.5.8.4 Soot and other solid or liquid combustion products
settle on the optical surfaces during a test, resulting in
8 9
Some of these limitations are common to many small scale fire-test-response Theboldfacenumbersinparenthesesrefertothelistofreferencesattheendof
methods. this standard.
E1995 − 21
potentially higher smoke density measurements than those due
to the smoke in suspension.
5.5.8.5 This test method does not carry out dynamic mea-
surementsassmokesimplycontinuesfillingaclosedchamber;
therefore, the smoke obscuration values obtained do not
represent conditions of open fires.
6. Apparatus and Ancillary Equipment
6.1 General—The apparatus (Fig. 1) consists of an air-tight
test chamber with provision for containing a sample holder,
radiationcone,pilotburner,alighttransmissionandmeasuring
system and other ancillary facilities for controlling the condi-
tions of operation during a test.
6.2 Test Chamber:
6.2.1 Construction:
6.2.1.1 Fabricate the test chamber (Figs. 1 and 2)from
NOTE 1—All dimensions in this figure are given in mm unless stated
laminated panels, the inner surfaces of which shall consist of
otherwise.
eitheraporcelain-enamelledmetal,notmorethan1 60.1mm
FIG. 2 Plan View of Typical Test Chamber
(0.04 6 0.004 in.) thick, or an equivalent coated metal, which
is resistant to chemical attack and corrosion and capable of
easycleaning.Theinternaldimensionsofthechambershallbe
6.2.1.2 Fit the chamber with a safety blow-out panel,
914 6 3 mm long, 914 6 3 mm high and 610 6 3 mm deep
consisting of a sheet of aluminum foil of thickness not greater
-3
(36 6 0.1 in. by 36 6 0.1 in. by 24 6 0.1 in.) (Fig. 2, where
than0.04mm(1.6×10 in.)andhavingaminimumareaof80
2 2
thenumbersaredimensions,inmm).Providethechamberwith
600 mm (125 in. ), fastened in such a way as to provide an
a hinged front-mounted door with an observation window and
airtight seal. Figs. 1 and 2 show the blow-out panel location.
a removable opaque door cover to the window to prevent light
6.2.1.3 Mounttwoopticalwindows,eachwithadiameterof
entering the chamber.
75 61mm(3 6 0.04 in.), one each in the top and bottom of
the cabinet, at the position shown in Fig. 2, with their interior
faces flush with the outside of the cabinet lining. Provide the
underside of the window on the floor with an electric heater of
9 61Wcapacity,intheformofaring,whichshallbecapable
Alist of suppliers for such equipment is available fromASTM Headquarters.
of maintaining the upper surface of the window at a tempera-
ture just sufficient to minimize smoke condensation on that
face. Mount the heater around the window edge so as not to
interrupt the light path (Fig. 2).
6.2.1.4 Mountopticalplatforms,8 60.1mm(0.31 60.004
in.) thick, around the windows on the outside of the chamber
andholdthemrigidlyinpositionrelativetoeachotherbythree
metal rods, with a diameter of at least 12.5 mm (0.5 in.),
extending through the chamber and fastened securely to the
platforms.
6.2.1.5 Provideotheropeningsinthecabinetforservices,as
specified. They shall be capable of being closed so as to
develop a positive pressure of up to 1.5-kPa (150-mm water
gage) above atmospheric pressure inside the chamber (see
6.2.2) and maintained when checked in accordance with 6.6
and 9.6. All components of the chamber shall be capable of
withstandingagreaterinternalpositivepressurethanthesafety
blow-out panel.
6.2.1.6 Provide an inlet vent with shutter in the front of the
chamber at the top and away from the radiator cone. Also,
provide an exhaust vent with shutter in the bottom of the
chamber to lead, via flexible pipe with a diameter of 50 to 100
Stainless steel wire mesh for fastening the aluminum foil, offers adequate
protection for the blow-out panel.
A window temperature of at least 50-55 °C (122-131 °F) has been found
FIG. 1 Typical Arrangement of Test Chamber suitable and normally is achieved with a 9W heater.
E1995 − 21
NOTE 1—All dimensions in this figure are given in mm unless stated otherwise.
FIG. 3 Typical Chamber Pressure Relief Manometer
NOTE 1—All dimensions in this figure are given in mm unless stated otherwise.
FIG. 4 Cross-sectional View Through the Radiator Cone Heater
mm (2 to 4 in.), to an extraction fan capable of creating a 6.2.2 Sensor for Chamber Pressure Measurements—Apres-
negative pressure of at least 0.5-kPa (50-mm water gage). sure sensor (for example, a manometer or pressure transducer)
E1995 − 21
system shall be suitable for measuring temperatures in the
range of 35 to 60 °C (64 to 140 °F) (see 11.1.4).
6.3 Sample Support and Heating Arrangements:
6.3.1 Radiator Cone:
6.3.1.1 The radiator cone (Fig. 4) shall consist of a heating
element, of nominal rating 450W, contained within a stainless
steeltube,2210 65mm(87 60.2in.)inlengthand6.5 60.2
mm (0.25 6 0.008 in.) in diameter, coiled into the shape of a
truncated cone and fitted into a shade.The shade shall have an
overall height of 45 6 0.04 mm (1.8 6 0.02 in.), an internal
diameter of 55 6 1 mm (2.2 6 0.04 in.) and an internal base
diameterof110 63mm(4.3 60.1in.).Itshallconsistoftwo
layers of 1 6 0.1 mm (0.04 6 0.004-in.) thick stainless steel
witha10 60.5-mm(0.4 60.02-in.)thicknessofceramicfibre
3 3
insulation of nominal density 100 kg/m (6.2 lb/ft ), sand-
wiched between them. Clamp the heating element by two
plates at the top and bottom of the element (see also Appendix
NOTE 1—All dimensions in this figure are given in mm unless stated
otherwise. X1).
FIG. 5 Typical Framework for Support of Radiator Cone, Speci-
6.3.1.2 The radiator cone shall be capable of providing
men and Flux Meter
irradiance in the range 10 to 50 kW/m , at the center of the
surface of the specimen. The irradiance shall also be deter-
mined at a position of 25 62mm(1 6 0.08 in.) to each side
of the specimen center, and the irradiance at these two
positionsshallbenotlessthan85%,andnotmorethan115%,
of the irradiance at the center of the specimen.
6.3.1.3 The irradiance of the radiator cone shall be con-
trolled by reference to the averaged reading of two type K
thermocouples. The thermocouples shall be 1.6 6 0.2 mm
(0.055 to 0.071 in.) outside diameter, sheathed with an unex-
posed hot junction, mounted diametrically opposite, in contact
with, but not welded to, the heating element, and positioned at
onethirdofthedistancefromthetopsurfaceofthecone.Ithas
been found that thermocouples of equal length and wired in
parallel to the temperature controller perform adequately;
alternate wiring methods shown to give equivalent results also
are acceptable (see also Appendix X2).
6.3.1.4 The temperature at the heater is to be controlled and
shall be held steady to 62°C(64 °F). The temperature
controller for the radiator cone shall be of the proportional,
NOTE 1—The dimensions in this figure are given in mm unless stated
integral and derivative Type 3-term controller with thyristor
otherwise.
stack fast-cycle or phase angle control of not less than 10 A
FIG. 6 Typical Arrangement of Radiator Cone, Specimen Holder
and Radiator Shield (Side View)
max rating. Capacity for adjustment of integral time between
10 s and 50 s and differential time between 25 s and 30 s shall
be provided to permit reasonable matching with the response
with a range up to 6 in. (152 mm) of water (1.5 kPa) shall be
characteristics of the heater.Atemperature input range of 0 to
provided to monitor chamber pressure and leakage. The
1000°C(32to1832°F)issuitable;anirradianceof50kW/m
pressure measurement point shall be through a gas sampling
will be given by a heater temperature in the 700 to 750 °C
port in the chamber.
(1292 to 1382 °F) temperature range.Automatic cold junction
6.2.3 Chamber Pressure Relief System—A simple water
compensation of the thermocouple shall be provided. The
column or relief valve shall be provided to permit control of
described design has been shown to be satisfactory; alternate
chamber pressure.
devices shown to give equivalent results are also acceptable.
6.2.4 Chamber Temperature—A thermocouple junction,
6.3.2 Framework for Support of the Radiator Cone, Speci-
made from wires of diameter not greater than 1 mm (0.04 in.),
men Holder, and Heat-Flux Meter:
shallbemountedontheinsideofthebackwallofthechamber,
atthegeometriccenter,bymeansofaninsulatingdisc,suchas
Sheathed chromel/alumel type K thermocouples have been found suitable for
polystyrene foam, with a thickness of 6.5 6 0.2 mm (0.25 in.)
this purpose.
and a diameter of not more than 20 mm (0.8 in.) attached with
While phase angle control is allowed for the temperature controller of the
a suitable cement. The thermocouple junction shall be con-
radiator cone, it must be noted that this usually will require electrical filtering to
nected to a recorder, meter, or data acquisition unit, and the avoid the risk of inducing noise in low signal level lines.
E1995 − 21
6.3.2.1 The radiator cone shall be secured from the vertical 6.3.4.1 The heat flux meter shall be of the Schmidt-Boelter
rodsofthesupportframeworkandlocatedsothatthelowerrim (thermopile) type, with a design range of at least 50 kW/m .
of the radiator cone shade is 25 61mm(1 6 0.04 in.) above The sensing surface of the heat flux meter (Fig. 5) shall have a
the upper surface of the specimen, when oriented in the flat, circular face of 10 61-mm (0.4 6 0.04-in.) diameter,
horizontal position. Details of the radiator cone and supports coated with a durable matt black finish. The heat flux meter
17, 18
are shown in Figs. 5 and 6. The base of the specimen holder shallbewater-cooled andshallhaveanaccuracyof 63%
contains a height adjustment device to ensure a consistent (see also Appendix X2).
distance between radiator cone and specimen surface. 6.3.4.2 The heat flux meter shall be connected directly to a
6.3.3 Radiation Shield—The cone heater shall be provided suitable recorder, or data acquisition unit (6.8.6), so that it is
witharemovableradiationshieldtoprotectthespecimenfrom capable,whencalibrated,ofrecordingheatfluxesof25kW/m
2 19
the irradiance prior to the start of the test. The radiation shield and 50 kW/m .
shallbemadeofnoncombustiblematerialwithatotalthickness 6.3.4.3 Forcalibrationoftheheatfluxmetersystem,see9.8.
not to exceed 12 mm. The radiation shield shall comply with 6.3.5 Specimen Holders:
either 6.3.3.1 or 6.3.3.2 and shall be kept in place for a
maximum period of 10s.
6.3.3.1 A water-cooled radiation shield coated with a du-
rable matte black finish of surface emissivity e = 0.95 6 0.05;
or,
NOTE 1—The dimensions in this figure are given in mm unless stated
otherwise.
FIG. 8 Typical Arrangement of Radiator Cone, Specimen Holder
and Radiator Shield (Front View)
6.3.5.1 Details of the specimen holder are shown in Fig. 7.
Thebaseshallbelinedwithalowdensity(nominally65kg/m
(4lb/ft ))refractoryfibreblanket,withaminimumthicknessof
10 mm (0.4 in.).
6.3.5.2 A retainer frame and wire grid shall be used for all
tests. The wire grid shall be 75 61mm(3 6 0.04-in.) square
with 20 6 0.5 mm (0.8 6 0.02 in.) square holes constructed
NOTE 1—The dimensions in this figure are given in mm unless stated
from2 60.2mm(0.08 60.008in.)stainlesssteelrod,welded
otherwise.
at all intersections.
FIG. 7 Specimen Holder
6.3.6 Pilot Burner:
6.3.3.2 A radiation shield with a reflective top surface in
If the cooling temperature is lower than the temperature at which the gage is
order to minimize radiation transfer but not water-cooled.
calibrated, condensation on the sensor is possible and would lead to serious
measurement errors.
6.3.3.3 The radiation shield shall be equipped with a handle
The manufacturer of Schmidt-Boelter gages has the following specifications
or other suitable means for quick insertion and removal. The
for cooling water: pressure 413-621 kPa, temperature 20.0–26.6°C and flow rate
cone heater base plate shall be equipped with the means for
0.76–1.14 L/min.
holding the radiation shield in position and allowing its easy If a chart recorder which only displays a millivolt output is used, the millivolt
value shall be converted to heat flux, in kW/m , using the calibration factor (or
and quick removal.
equation, if appropriate) specific to the heat flux meter.
6.3.4 Heat Flux Meter:
The retainer frame and wire grid particularly are appropriate when testing
intumescing specimens and also for reducing unrepresentative edge combustion of
composite samples or for retaining specimens prone to delamination. The wire grid
It is possible that the use of a radiation shield for periods longer than 10s will is likely to affect the test results, compared to tests conducted in its absence;
affect radiator heat control and, consequently, the heat-flux level applied to the however,itsuseisrecommendedforseveralreasons:ithelpstopromoteuniformity
specimen. in testing by different laboratories, in view of the expected effect of the retainer
Thisdeviceisnecessaryinordertoenablerepeatteststobecarriedoutwithout frame and wire grid on test results, it is needed for certain specimens, as explained
switching off the radiator cone. above, and it is required in ISO5659–2.
E1995 − 21
-4 3
6.3.6.1 Theflamefromthesingle-flameburner,Fig.8,shall (18×10 ft /min) flow rates and that for air a value of 500
3 -3 3
have a length of 30 6 5 mm (1.2 6 0.2 in.) and shall be cm /min (18 × 10 ft /min). Alternate devices shown to give
positioned horizontally 10 6 1 mm (0.4 6 0.04 in.) above the equivalent results are also acceptable.
top face of the specimen. The color of the flame shall be blue,
6.5 Photometric System:
with a yellow tip. Ensure that the tip of the burner is aligned
6.5.1 General:
with the edge of the specimen, as shown in Fig. 9.
6.5.1.1 The photometric system shall consist of a light
6.3.6.2 Installasmallsparkignitiondevice,sitednexttothe
source and lens in a light-tight housing mounted below the
outlet tube of the burner, for the operator to cause reignition of
opticalwindowinthefloorofthecabinet,andaphoto-detector
the flame without opening the door of the chamber.Asuitable
with lens, filters and shutter in a light-tight housing above the
system is a spark plug witha3mm (0.11-in.) gap, powered
optical window in the top of the chamber.
from a 10-kV transformer. A suitable transformer is of a type
6.5.1.2 The system shall be as shown in Fig. 10. Equipment
specifically designed for spark-ignition use, with an isolated
shall be provided to control the output of the light source and
(ungrounded) secondary to minimize interference with the
to measure the amount of light falling on the photo-detector.
data-transmission lines. An acceptable electrode length and
6.5.2 Light Source:
sparkpluglocationissuchthatthesparkgapislocated13mm
6.5.2.1 The light source shall be a 6.5Vincandescent lamp.
(0.5 in.) above the specimen, close to the pilot burner.
Power for the lamp shall be provided by a transformer
6.4 Gas Supply: producing 6.5Vand a rheostat so that the r.m.s. voltage across
6.4.1 Amixture of propane, of at least 95% purity and at a the lamp, as determined by a voltmeter, is maintained at 4 6
pressure of 3.5 6 1-kPa (350 6 100-mm water gage), and air 0.2 V. The lamp shall be mounted in the lower light-tight box,
at a pressure of 170 6 30-kPa (17 6 3-m water gage) shall be and a lens to provide a collimated light beam of 51 mm (2-in.)
suppliedtotheburner.Eachgasshallbefedtoapointatwhich diameter, passing towards and through the optical window on
they are mixed and supplied to the burner. the floor of the chamber, shall be mounted, with provision for
6.4.2 The use of needle valves and calibrated flowmeters is adjustment, to control the collimated beam in direction and
a suitable method of controlling gas flows. The flowmeter for diameter. The housing shall be provided with a cover to allow
the propane supply shall be capable of measuring 50 cm /min access for adjustments to be made to the position of the lens.
NOTE 1—The dimensions in this figure are given in mm unless stated otherwise.
FIG. 9 Detailed Location of Pilot Burner
E1995 − 21
NOTE 1—The dimensions in this figure are given in mm unless stated otherwise.
FIG. 10 Photometric System
6.5.3 Photo-Detector: reading to be obtained with a 0.5 neutral density filter and an
6.5.3.1 Thelight-measuringdevicesystemshallconsistofa ND-2 range extension filter (see 6.5.3.2) in the light path.
photo-multiplier tube connected to a multirange amplifier Provision shall be made for adjusting the reading of the
coupled to a recording device, or data acquisition unit (6.8.6), instrument under given conditions over the full range of any
capable of measuring continuously relative light intensity scale.
againsttimeaspercentagetransmissionoveratleastfiveorders 6.5.3.2 The photo-multiplier tube shall be mounted in the
of magnitude, with an S-4 spectral sensitivity response similar upper section of the detector housing. Below it, there shall be
-9
tothatofhumanvisionandadarkcurrentlessthan10 A.The anassemblywhichprovidesfortherapidpositioningofafilter
system shall have a linear response with respect to transmit-
tance and an accuracy of better than 6 3% of the maximum
The required accuracy of the photo-detector is obtained more easily if the
readingonanyrange.Forselectionofphotomultipliertubes,as
measuring systems incorporate scale ranges of 30, 3, 0.3, etc., as well as ranges of
applicable, the minimum sensitivity shall allow a 100% 100, 10, 1, etc.
E1995 − 21
and of a shutter, in or out of the path of the collimated light chamber after each test. Clean the top window first, then the
beam, each being operated separately. The filter, referred to as bottom window, using a nonabrasive cloth dampened with a
the range-extension filter (ND-2), shall be a glass neutral suitable cleaner. Dry the window to prevent streaking or film
density filter of nominal optical density 2. When in the closed buildup.Donotuseanycleanersthatcontainwaxbecausewax
position, the shutter shall prevent all light in the test chamber will cause the smoke to adsorb to the glass more quickly.
from reaching the photo-multiplier tube.An opal diffuser shall 6.7.2 Viewing Window—Clean the viewing window
be mounted permanently below the shutter. periodically,asrequired,toallowviewingthechamberinterior
6.5.3.3 The lower part of the housing shall support a 51 6 during testing.
1mm(2 6 0.04-in.) diameter lens, capable of being adjusted 6.7.3 Chamber Walls—Clean the chamber walls periodi-
so that the collimated beam is focused to form a small intense cally to prevent excessive build-up of smoke products. An
spot of light at the disc aperture between the upper and lower ammoniated spray detergent and soft scouring pads have been
partsofthehousing.Abovethelens,thereshallbeamountfor found effective for cleaning the chamber walls.
supporting one or more compensating filters from a set of nine 6.7.4 Specimen Holders—Remove any charred residues on
gelatinneutraldensityfilters,withopticaldensityvaryingfrom the specimen holders and horizontal rods securing the holder
0.1 to 0.9 in steps of 0.1. The housing shall be provided with position to prevent contamination of subsequent specimens.
a cover, to allow access for adjustments to be made to the
6.8 Ancillary Equipment:
position of the lens and for inserting or removing filters.
6.8.1 Balance—Useabalancewithacapacityexceedingthe
6.5.3.4 A neutral density filter, with a nominal optical
massofthespecimenandwhichshallbereadableandaccurate
densityof3.0,largeenoughtocovertheloweropticalwindow,
to 0.5% of the specimen mass.
the actual optical density having been determined by
6.8.2 Timing Device—Use a timing device capable of re-
calibration, shall be available for calibrating the photometric
cording elapsed time to the nearest second, over a period of at
system.
least 1 hour, with an accuracy of 1s in 1 hour, for timing
6.5.4 Additional Equipment:
operations and observations.
6.5.4.1 A template for checking the collimated light beam
6.8.3 Linear Measuring Devices—Use rules, calipers,
shall consist of an opaque disc marked with a concentric ring
gages, or other devices of suitable accuracy, for checking all
of 51 61mm(2 6 0.04-in.) diameter, shall be capable of
dimensions specified with given tolerances.
fittingsnuglybetweenthesupportpillars.Itshallbecapableof
6.8.4 Auxiliary Heater—Use an auxiliary heater of 500 W
being attached to, and centered on, the underside of the upper
capacity, capable of raising the air temperature uniformly
optical window in the chamber.
without local heating of the walls, if required, to help the
6.5.4.2 A piece of white cloth, paper tissue or a neutral
chambertoreachthestabilizedtemperaturemorerapidlyunder
density filter of sufficient size to cover completely the lower
adverse conditions.
optical window of the chamber and capable of transmitting a
6.8.5 Protective Equipment—Protective clothing, such as
sufficient amount of light to give a midscale reading of the
gloves, goggles, respirators, and handling equipment, such as
photometricsystemwhenswitchedtothescalewitharangeof
tongs, always shall be available and shall be used when the
1% transmission, shall be available for calibrating the range-
type of sample being tested demands them (see Section 7).
extender filter.
6.8.6 Data Acquisition—Use a recorder, or a data acquisi-
6.5.4.3 A piece of opaque material, sufficiently large to
tion unit, capable of continuously recording the millivolt
covertheloweropticalwindow,shallbeavailableforblocking
output of the photo-detector (6.5.3) to an accuracy of better
the light from the light source entering the chamber.
than 0.5% of full-range deflection. The device used also shall
6.6 Chamber Leakage—With the specified items of equip- becapableofrecordingtheheat-fluxmeteroutput(see6.3.4.2)
ment assembled properly and ready for test, the chamber shall to the required accuracy. If a data acquisition unit is used, the
be sufficiently air-tight to comply with the requirements of the datacollectionintervalsshallbe5sorless.Ifarecorderisused,
leakage rate test given in 9.6. the recording chart drive shall be used at a minimum chart
speed of 10 mm/min (0.4 in./min).
6.7 Cleaning Materials—Conduct periodic cleaning to en-
6.8.7 Thermometer—Use a thermometer, or a Type K
sure proper operation (see also 11.1.2). Have available appro-
thermocouple, capable of measuring temperature over the
priate materials for cleaning the inside of the chamber. The
range 20 to 100 °C (68 to 212 °F), to an accuracy of 6 0.5 °C
optical system windows, viewing window, chamber walls, and
(6 0.9 °F), for determining ambient temperature or any other
specimen holders must all be cleaned regularly. A recom-
needed temperature.
mended cleaning procedure is presented in 6.7.1 – 6.7.4.
6.8.8 Water Circulating Device—Use a device for water
6.7.1 Optical System Windows Recommended Procedure—
circulation to cool the heat-flux meter.
Clean the exposed surfaces of the glass separating the photo-
detector and light source housings from the interior of the 6.9 Test Environment:
6.9.1 Protect the test apparatus from direct sunlight or any
strong light source to avoid the possibility of spurious light
Handleallfiltersbytheiredges,becausefingerprintsgreatlyaffecttheirrating. readings.
Do not attempt to clean the surface of a filter; once the surface has been damaged
replace the filter.
23 24
The most likely sources of leakage have been found to be the door seal, the Ethyl alcohol, ethyl ketone, or equivalent, and soft tissue have been found
inlet and outlet vents and the safety blow-out panel. effective for cleaning the optical windows and the viewing window.
E1995 − 21
6.9.2 Make adequate provision for removing potentially the samples at their full end-use thickness. It is recommended
hazardous and objectionable smoke and gases from the area of that materials for which end-use thickness is not available be
operation. Also, take suitable precautions to prevent exposure testedatathicknessof1.0 60.1mm(0.04 60.004in.),unless
oftheoperatortosuchgases,particularlyduringtheremovalof otherwise specified in the material or performance standard or
specimens from the chamber or when cleaning the apparatus. specification.
8.6.3 Samples with a thickness greater than 25 mm (1 in.)
7. Operator Safety shall be cut to give a specimen thickness of 25 61mm(1 6
0.04 in.), in such a way that the original (uncut) face is
7.1 Warning—This test procedure involves high tempera-
evaluated.
turesandcombustionprocesses;therefore,itispossibleforeye
8.6.4 Samples of multilayer materials, products, or
injuries,burns,ignitionofextraneousobjects,andinhalationof
assemblies, with a thickness greater than 25 mm (1 in.),
smoke or combustion products to occur, unless proper precau-
consisting of core material(s) with facings of different materi-
tions are taken. To avoid accidental leakage of toxic combus-
als shall be prepared in accordance with 8.6.3, by cutting from
tion products into the surrounding atmosphere, it is advisable
the layers behind the facing one (see also 8.7.2).
to evacuate the chamber, at the end of a test, into an exhaust
system with adequate capacity. The operator must use heavy
8.7 Specimen Assembly and Mounting:
gloves,safetytongs,orothersuitableprotectionforremovalof
8.7.1 General—The specimen shall be representative of the
thespecimenholder.Theventingmustbecheckedperiodically
materials or composite and shall be prepared in accordance
for proper operation.
with recommended application procedures. Flat sections of the
same thickness and composition are to be tested rather than
8. Test Specimen
curved, molded, or specialty parts. Substrate or core materials
for the test specimens shall be the same as those for the
8.1 Suitability of Sample for Testing:
intendedapplication.Ifamaterialorassemblyhasthepotential
8.1.1 The method is suitable for essentially flat specimens
tobeexposedtoafireoneitherside,bothsidesshallbetested.
only (see 3.2.3).
If an adhesive is intended for field application of a finish
8.1.2 The results of this test method are sensitive to varia-
material or substrate, the prescribed type of adhesive and the
tions in surface characteristics, thickness of individual layers,
spreadingraterecommendedforfieldapplicationoftheassem-
overall thickness, mass, and composition.
bly of test specimen shall be used and the details shall be
8.1.3 When preparing replicate specimens for testing, take
reported.
precautions to ensure all specimens fall within the require-
8.7.2 Finish Materials—Finish materials, including sheet
ments in 8.6. Keep individual records of the mass of each
laminates, tiles, fabrics, and others secured to a substrate
specimen together with the individual test data of that speci-
materialwithadhesive,andcompositematerialsnotattachedto
men.
a substrate, have the potential to be subject to delamination,
8.2 If the top and bottom faces of samples submitted for
cracking, peeling, or other separations affecting their smoke
evaluation by this test method are different from one another,
generation. To evaluate these effects, it is often necessary to
evaluate both faces if it is possible that each face will be
perform supplementary tests on a scored (split) exposed
exposed to fire when in use.
surface, or on interior layers or surfaces. When supplementary
8.3 Aminimumofsixspecimensshallbetestedsothatthree
tests are conducted for this purpose, the manner of performing
specimens are tested at each one of the two required condi-
suchsupplementarytests,andthetestresults,shallbeincluded
tions. Unless specified otherwise by the test requester, the
in the report, together with the test results from the conven-
standardexposureconditionsareflamingatanirradianceof25
tional tests.
2 2
kW/m , and flaming at an irradiance of 50 kW/m .
8.7.2.1 Finish Materials without Substrate or Core—For
comparativetestsoffinishmaterialswithoutanormalsubstrate
NOTE 2—Optional testing modes include nonflaming, at an irradiance
or core, and for screening purposes only, the following
of 25 kW/m (needed if comparison is required with the test results from
Test Method E662), and nonflaming, at an irradiance of 50 kW/m
procedures shall be employed:
(needed if comparison is required with the test results from ISO 5659-2).
8.7.2.2 Rigid or semirigid sheet materials shall be tested by
These additional exposures are not mandatory (see also X1.4.9). Other
the standard procedure regardless of thickne
...