Standard Test Method for Density of Smoke from the Burning or Decomposition of Plastics

SCOPE
1.1 This fire-test-response test method covers a laboratory procedure for measuring and observing the relative amounts of smoke obscuration produced by the burning or decomposition of plastics. It is intended to be used for measuring the smoke-producing characteristics of plastics under controlled conditions of combustion or decomposition. Correlation with other fire conditions is not implied. The measurements are made in terms of the loss of light transmission through a collected volume of smoke produced under controlled, standardized conditions. The apparatus is constructed so that the flame and smoke can be observed during the test.  
1.2 Caution-During the course of combustion, gases or vapors, or both, are evolved that may be hazardous to personnel. Adequate precautions should be taken to protect the operator.
1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information purposes only.
1.4 This standard should be used to measure and describe the response of materials, products, or assemblies to heat and flame under controlled laboratory conditions and should not be used to describe or appraise the fire-hazard or fire-risk of materials, products, or assemblies under actual fire conditions. However, results of this test may be used as elements of a fire-hazard assessment or a fire risk assessment which takes into account all of the factors which are pertinent to an assessment of the fire hazard or fire-risk of a particular end use.  
1.5 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in 1.2 and Note 7.  Note 1-There is no similar or equivalent ISO standard.

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Historical
Publication Date
29-Feb-2004
Technical Committee
Drafting Committee
Current Stage
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ASTM D2843-99(2004) - Standard Test Method for Density of Smoke from the Burning or Decomposition of Plastics
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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:D2843–99 (Reapproved 2004)
Standard Test Method for
Density of Smoke from the Burning or Decomposition of
Plastics
This standard is issued under the fixed designation D 2843; 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.
This standard has been approved for use by agencies of the Department of Defense.
1. Scope* bility of regulatory limitations prior to use. Specific warning
statements are given in 1.2 and 9.11.
1.1 This fire-test-response test method covers a laboratory
procedure for measuring and observing the relative amounts of
NOTE 1—There is no similar or equivalent ISO standard.
smoke obscuration produced by the burning or decomposition
2. Referenced Documents
of plastics. It is intended to be used for measuring the
smoke-producing characteristics of plastics under controlled
2.1 ASTM Standards:
conditions of combustion or decomposition. Correlation with
D 618 Practice for Conditioning Plastics for Testing
other fire conditions is not implied. The measurements are
D 883 Terminology Relating to Plastics
made in terms of the loss of light transmission through a
D 1600 Terminology for Abbreviated Terms Relating to
collected volume of smoke produced under controlled, stan-
Plastics
dardized conditions. The apparatus is constructed so that the
E 84 Test Method for Surface Burning Characteristics of
flame and smoke can be observed during the test.
Building Materials
1.2 Warning—During the course of combustion, gases or
E 176 Terminology for Fire Standards
vapors, or both, are evolved that may be hazardous to person-
E 662 Test Method for Specific Optical Density of Smoke
nel. Adequate precautions should be taken to protect the
Generated by Solid Materials
operator.
E 691 Practice for Conducting an Interlaboratory Study to
1.3 The values stated in SI units are to be regarded as the
Determine the Precision of a Test Method
standard. The values given in brackets are for information
E 906 Test Method for Heat and Visible Smoke Release
purposes only.
Rates for Materials and Products
1.4 This standard should be used to measure and describe
E 1354 Test Method for Heat and Visible Smoke Release
the response of materials, products, or assemblies to heat and
Rates for Materials and Products Using an Oxygen Con-
flame under controlled laboratory conditions and should not be
sumption Colorimeter
used to describe or appraise the fire-hazard or fire-risk of
3. Terminology
materials, products, or assemblies under actual fire conditions.
However, results of this test may be used as elements of a
3.1 Definitions—Theterminologyusedinthistestmethodis
fire-hazard assessment or a fire risk assessment which takes in accordance with Terminologies D 883 and D 1600 (terms
into account all of the factors which are pertinent to an
relating to plastics) and Terminology E 176 (terms relating to
assessment of the fire hazard or fire-risk of a particular end fire).
use.
4. Summary of Test Method
1.5 This standard does not purport to address all of the
safety problems, if any, associated with its use. It is the 4.1 Thetestspecimenisexposedtoflameforthedurationof
responsibility of the user of this standard to establish appro- the test, and the smoke is substantially trapped in the chamber
priate safety and health practices and determine the applica- in which combustion occurs. A 25 by 25 by 6-mm [1 by 1 by
⁄4-in.] specimen is placed on supporting metal screen and
burned in a laboratory test chamber (Fig. 1) under active flame
conditions using a propane burner operating at a pressure of
This test method is under the jurisdiction ofASTM Committee D20 on Plastics
276 kPa [40 psi]. The 300 by 300 by 790-mm [12 by 12 by
and is the direct responsibility of Subcommittee D20.30 on Thermal Properties-
(Section D20.30.03).
Current edition approved March 1, 2004. Published June 2004. Originally
approved in 1970. Last previous edition approved in 1999 as D 2843 - 99. For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Anonymous, “A Method of Measuring Smoke Density,” NFPA Quarterly, contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
QNFPA, Vol 57, January 1964, p. 276. Reprint NFPAQ57-9.Available from NFPA, Standards volume information, refer to the standard’s Document Summary page on
60 Batterymarch St., Boston, MA 02110. the ASTM website.
*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.
D2843–99 (2004)
1. Specimen Holder
A Stainless steel screen
B Asbestos sheet
C Adjusting knob
D Quench pan
2. Ignition
A Burner 4. Photometer
B Propane tank A Visual system (exit sign)
C Gas shut-off valve B Measuring system
D Pressure regulator adjustment 1 Light source and adjusting transformer
E Pressure indicator 2 Photronic cell and grid (to block stray light)
F Burner-positioning knob 3 Meter (indicating percent of light absorbed)
3. Cabinet (shown without door) 4 Temperature compensation
A Hinges (door gasketed three sides) 5 Photocell temperature monitor
B Vents (25-mm [1-in.] high opening four sides) 6 Range change
C Blower (damper on mounting side) 5. Timer
D Control (blower on when damper is open) A Indicator, 0 to 5 min (friction reset)
FIG. 1 Schematic Diagram of Smoke Chamber
D2843–99 (2004)
31-in.] test chamber is instrumented with a light source, 6. Apparatus
photoelectric cell, and meter to measure light absorption
6.1 The smoke chamber shall be constructed essentially as
horizontally across the 300-mm [12-in.] light beam path. The 5
shown in Fig. 1.
chamber is closed during the 4-min test period except for the
6.1.1 Chamber:
25-m [1-in.] high ventilation openings around the bottom.
6.1.1.1 The chamber shall consist of a 14-gage (B & S) 300
4.2 The light-absorption data are plotted versus time. A
by 300 by 790-mm [12 by 12 by 31-in.] aluminum box to
typical plot is shown in Fig. 2.Two indexes are used to rate the
which is hinged a heat-resistant glass glazed door. This box
material:themaximumsmokeproducedandthesmoke-density
shall be mounted on a 350 by 400 by 57-mm [14 by 16 by
rating.
2 ⁄4-in.] base which houses the controls. Dependent upon the
materials tested, the metal may require protection from corro-
5. Significance and Use
sion.
6.1.1.2 The chamber shall be sealed except for 25 by
5.1 Tests made on a material under conditions herein
230-mm [1 by 9-in.] openings on the four sides of the bottom
prescribed can be of considerable value in comparing the
of the chamber. A1700-L/min [60-ft /min] blower shall be
relative smoke obscuration characteristics of plastics.
mounted on one side of the chamber. The inlet duct to the
5.2 This test method serves to determine the extent to which
blower shall be equipped with a close-fitting damper. The
plastic materials are likely to smoke under conditions of active
outlet of the blower shall be connected through a duct to the
burning and decomposition in the presence of flame.
laboratory exhaust system. If the chamber is in a ventilated
hood, no connection to the lab exhaust system through a duct
NOTE 2—The visual and instrumental observations from this test
is needed.
compare well with the visual observations of the smoke generated by
6.1.1.3 The two sides adjacent to the door shall be fitted
plastic materials when added to a freely burning large outdoor fire.
with 70-mm [2 ⁄4 in.] diameter smoke-tight glazed areas
5.3 The usefulness of this test procedure is in its ability to
centered 480 mm [19 ⁄4 in.] above the base.At these locations
measure the amount of smoke obscuration produced in a
and outside the chamber, boxes containing the optical equip-
simple, direct, and meaningful manner under the specified
ment and additional controls shall be attached.
conditions. The degree of obscuration of vision by smoke
6.1.1.4 A removable white plastic plate shall be attached to
generated by combustibles can be substantially affected by
the back of the chamber. There shall be a 90 by 150-mm [3 ⁄2
changes in quantity and form of material, humidity, draft,
by 6-in.] clear area centered about 480 mm above the bottom
temperature, and oxygen supply.
Detailed drawings of the smoke chamber are also available at a nominal cost
from ASTM Headquarters. Order Adjunct : ADJD2843. A smoke chamber meeting
4 the requirements of this test method is available from United States Testing
Bartosic, A. J., and Rarig, F. J., “Evaluation of the XP2 Smoke Density
Company, Inc., 1415 Park Ave., Hoboken, NJ 07030.
Chamber,” Symposium on Fire Test Methods—Restraint & Smoke, ASTM STP 422,
ASTM, Philadelphia, PA, 1966.
FIG. 2 Light Absorption versus Time
D2843–99 (2004)
NOTE 4—Since the orifice provides the metering effect proportionate to
of the chamber through which is seen an illuminated white-
the supply pressure, care must be taken that the orifice is the only means
on-red exit sign. The white background permits observation of
of fuel egress.
the flame, smoke, and burning characteristics of the material.
The viewing of the exit sign helps to correlate visibility and
6.1.3.2 The burner shall be capable of being positioned
measured values.
quickly under the specimen so that the axis of the burner falls
6.1.2 Specimen Holder: 3
onalinepassingthroughapoint8mm[ ⁄10 in.]abovethebase
6.1.2.1 The specimen shall be supported on a 64-mm
at one back corner of the chamber extending diagonally across
1 1 1
[2 ⁄2-in.] square of 6 by 6-mm, 0.9-mm gage [ ⁄4 by ⁄4-in.,
the chamber and sloping upward at 45 deg with the base. The
0.035-in. gage] stainless steel wire cloth 220 mm [8 ⁄4 in.]
exit opening of the burner shall be 260 mm [10 ⁄4 in.] from the
above the base and equidistant from all sides of the chamber.
reference point at the rear of the chamber.
Thisscreenshalllieinastainlesssteelbezelsupportedbyarod
6.1.3.3 Aductatleast150mm[6in.]outsideofthechamber
through the right side of the chamber. From the same rod, a
shall provide the air piped to the burner.
similar bezel shall be located 76 mm [3 in.] below, and it shall
6.1.3.4 Propane pressure shall be adjustable and preferably
support a square of asbestos paper which catches any particles
automatically regulated. Propane pressure shall be indicated by
thatmaydripfromthespecimenduringthetest.Byrotatingthe
means of a Bourdon tube gage.
specimen holder rod, the burning specimen can be quenched in
6.1.4 Photometric System:
a shallow pan of water positioned below the specimen holder.
6.1.3 Ignition System:
6.1.4.1 Alight source, a barrier-layer photoelectric cell, and
6.1.3.1 The specimen shall be ignited by a propane flame
a temperature compensated meter shall be used to measure the
from a burner operating at a pressure of 276 kPa [40 psi]. The
proportion of a light beam which penetrates a 300-mm [12-in.]
fuel (Note 3) shall be mixed with air which has been propelled
path through the smoke. The light path shall be arranged
through the burner by the venturi effect of the propane as it
horizontally as shown in Fig. 4.
passes from a 0.13-mm [0.0005-in.] diameter orifice (Note 4),
6.1.4.2 The light source shall be mounted in a box (4B1 in
and the burner shall be assembled as shown in the exploded
Fig. 1) extending from the left side of the chamber at the mean
view of the burner in Fig. 3. The burner must be designed to 3
height of 480 mm [19 ⁄4 in.] above the base. The light source
provide adequate outside air.
shall be a compact filament microscope lamp No. 1493
operated at 5.8Vand a spherical reflector, with power supplied
NOTE 3—Commercial grade 85.0 % minimum, gross heating value
23 000 cal/litre [2590 Btu/ft ] propane meets the requirements. by a voltage-regulating transformer. A60 to 65-mm [2 ⁄2-in.]
FIG. 3 Exploded View of Burner
D2843–99 (2004)
T = Temperature-sensitive winding in or on meter case to increase in resistance in proportion to increase in meter resistance with temperature.
R = Potentiometer with calibrated scale to reduce resistance in proportion to decrease in photocell output with rise in temperature.
C = Potentiometer to calibrate total resistance of shunt to change meter sensitivity exactly by 10:1 ratio.
FIG. 4 Smoke Density Test Chamber Photometer
focal length lens shall focus a spot of light on the photocell in 7. Test Specimen
the right instrument panel.
7.1 The standard specimen shall be 25.4 6 0.3 by 25.4 6
6.1.4.3 Another box containing the photometer (4B2 in Fig. 1
0.3 by 6.2 6 0.3 mm [1 6 0.01 by 1 6 0.01 by ⁄4 6 0.01 in.].
1) shall be attached to the right side of the chamber. The
Thicknesses other than 6.2 mm [ ⁄4 in.] may be used and their
barrier-layer photoelectric cell shall have standard observer
size must be reported with the smoke density values (Note 6).
spectral response. An egg-crate grid in front of the photocell
Material thinner than 6.2 mm [ ⁄4 in.] may be tested, either in
shall be used to protect the cell from stray light. The grid shall
its normal use thickness, or by stacking and forming a
be finished in dull black and have openings at least twice as 1
composite specimen approximately 6.2 mm [ ⁄4 in.] thick.
deep as they are wide. The current produced by the photocell 1
Material thicker than 6.2 mm [ ⁄4 in.] may be tested either in its
isindicatedintermsofpercentlightabsorptiononameter.The
normal use thickness or by machining the material down to a
photocell linearity decreases as the temperature increases; 1
thickness of 6.2 mm [ ⁄4 in.].
compensations shall therefore be made.
NOTE 6—If specimens other than the standard specimen are to be used,
NOTE 5—Photocell manufacturers recommend operating the photocell
cooperating laboratories should agree upon preparation procedures and
at temperatures not exceeding 50°C.
dimensions of the specimen. The results in such cases may vary from the
results obtained with the standard specimen.
6.1.4.4 The meter shall have two ranges. The range change
shall be accomplished by shunting the meter to one tenth of its 7.2 The specimens shall be sanded, machined, or die cut in
sensitivity. When smoke accumulates to absorb 90 percent of a manner that produces a cut surface that is free from
the light beam, a momentary switch shall be depressed return- projecting fibers, chips, and ridges.
ing the meter to its basic sensitivity. By doing this the meter 7.3 The test sample shall consist of three
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