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NATIONAL BUREAU OF STANDARDS REPORT

9393

REVIEW OF PLASTICS FLAMMABILITY TEST METHODS

U.S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS
THE NATIONAL BUREAU OF STANDARDS

The National Bureau of Standards is a principal focal point in the Federal Government for assur- ing maximum application of the physical and engineering sciences to the advancement of technology

in industry and commerce. Its responsibilities include development and maintenance of the national

standards of measurement, and the provisions of means for making measurements consistent with

those standards; determination of physical constants and properties of materials; development of methods for testing materials, mechanisms, and structures, and making such tests as may be necessary, particularly for government agencies; cooperation in the establishment of standard practices

for incorporation in codes and specifications; advisory service to government agencies on scientific and technical problems; invention and development of devices to serve special needs -of the Govern- ment; assistance to industry, business, and consumers in the development and acceptance of commercial standards and simplified trade practice recommendations; administration of programs in cooperation with United States business groups and standards organizations for the development

of international standards of practice; and maintenance of a clearinghouse for the collection and

dissemination of scientific, technical, and engineering information. The scope of the Bureau’s

activities is suggested in the following listing of its three Institutes and their organizational units. Institute for Basic Standards. Applied Mathematics. Electricity. Metrology. Mechanics. Heat. Atomic Physics. Physical Chemistry. Laboratory Astrophysics.* Radiation Physics. Radio Standards

Laboratory:* Radio Standards Physics; Radio Standards Engineering. Office of Standard Reference

Data. Institute for Materials Research. Analytical Chemistry. Polymers. Metallurgy. Inorganic Materials. Reactor Radiations. Cryogenics.* Materials Evaluation Laboratory. Office of Standard Refer- ence Materials. Institute for Applied Technology. Building Research. Information Technology. Performance

Test Development. Electronic Instrumentation. Textile and Apparel Technology Center. Technical

Analysis. Office of Weights and Measures. Office of Engineering Standards. Office of Invention and

Innovation. Office of Technical Resources. Clearinghouse for Federal Scientific and Technical

Information.**

5 Located at Boulder, Colorado, 80301.

* ‘Located at 5285 Port Royal Road, Springfield, Virginia, 22171.
NATIONAL BUREAU OF STANDARDS REPORT

NBS PROJECT NBS REPORT

4215124 August 1966 9393

REVIEW OF PLASTICS FLAMMABILITY TEST METHODS

by

Mo Wo Samdholzer and M„ P. Vaishnav

NATIONAL BUREAU OF ST

for use within the Government, and review. For this reason, thi whole or in part, is not author Bureau of Standards, Washingti

the Report has been specifically

IMPORTANT NOTICE

ss accounting documents intended Approved for public release by the subjected to additional evaluation Director of the National Institute of listing of this Report- either in r . , , , ^ , , .

, 5 Office of the Director, National Standards and Technology (NIST) the Government agency for which on October 9, 2015 opies for its own use. <NBS>

i . S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS

Review of Plastics Flammability Test Methods

by

M. W. Sandholzer and M. P. Vaishnav

ABSTRACT

Continuing a review of the technical basis of the Flammable Fabrics Act,

a group of about 45 plastic materials were comparatively tested by the

flammability test of CS192-53 for "General Purpose Vinyl Film" and by

CS191-53 for the "Flammability of Clothing Textiles". On the basis of

the results obtained, use of the test method of CS191-53 for determinig

the flammability of both textile and plastic materials was recommended

for the purposes of the Federal law. Some comparative data were obtained on the burning rates of textiles and plastics tested in the

vertical position and in a position inclined at an angle of 45 degrees.

Further consideration was given to the problem of testing materials from

which standard sized test specimens cannot be cut, and recommendations

on procedure were developed.

1. INTRODUCTION

In connection with a review of the operation and effectiveness of the

Flammable Fabrics Act requested by the Secretary of Commerce, a detailed

study of the commercial standards which serve to define hazardous flammability under the law has been in process. Commercial Standard 191-53

on the "Flammability of Clothing Textiles", which covers the bulk of

clothing materials and has therefore been the primary flammability

criterion, was considered first and the work on that standard is presented in NBS Report 8933. The study has been continued to include the

flammability test procedure of Commercial Standard 192-53 on "General

Purpose Vinyl Plastic Film", which is also referenced in the law but

has not been called into extensive service because of the relatively

limited use of plastic films in wearing apparel. Recent trends suggest, however, that plastic materials in various forms are likely to

find increasing application in the clothing field, with the evaluation

of their flammability hazard becoming more important.

2. PROCUREMENT OF MATERIALS

In initial work to develop familiarity with the SPI flammability tester

(specified in CS192-53) and facility in its operation, various plastic

films on hand were used. Meanwhile, efforts were made to obtain a collection of plastic materials representative of those used in clothing

or conceivably suitable for clothing use. Procurement of a sizable

group of such materials presented something of a problem, however, in

view of their relatively limited clothing application and the fact that

the type of plastic appearing in garments offered on the market is
- 2 -

frequently not identified. Nevertheless, several garments were purchased

and, following an extensive program of letter inquiry to plastics manufacturers, 4-6 sq . yd. samples of about 25 plastic film or plastic coated

materials have been obtained to date. Not all of these materials are currently used in clothing necessarily, but were selected in some instances to represent a progressive variation in a given characteristic

(such as weight) for a particular plastic material. The information

supplied on the composition of the materials usually indicated only the

general type of plastic involved, such as vinyl, polyethylene, etc., and

in a few instances, even that was lacking.

3. COMPARATIVE DATA BY TWO TEST METHODS

In preliminary work with the tester, several points about the equipment

and technique were noted which appeared unduly complicated. Threading

the specimen holder, in particular, seemed awkward and time-consuming.

Furthermore, the obvious basic similarity of the method to that of CS191-53 suggested the possibility of using one test for both textiles and

plastics. To explore the feasibility of combining the flammability

determination and requirements for the two types of materials, a program of comparative testing by the two methods was organized.

Major points of similarity in the two methods include the general position in which the specimen is supported (45 degree angle), the width of

specimen exposed (1 1/2 inches), and the type of ignition (a microflame applied to the specimen surface) . They differ primarily in the

duration of exposure to the igniting flame , and in the aspects of the

flame spread which are noted and timed. In CS191-53 the igniting flame

is applied to the specimen surface for one second only, and the time

from first application of the flame until the burning of a thread 5 inches farther up the sample is automatically recorded. In CS192-53

the igniting flame remains in contact with the specimen indefinitely

and the time from first application of the flame until the burning of

a thread one inch farther up the specimen (called the ignition time)

and the time from the burning of the first thread to that of a second

thread 6 inches up the specimen from it (called the burning time) are automatically recorded. Addition of the ignition time and burning time

in the CS192-53 method would, therefore, appear to provide measurement

for a 7 inch length of specimen of a characteristic fairly comparable to

that measured for a 5 inch length of specimen in the CS191-53 method,

except for the difference in exposure to the igniting flame. In addition to the difference in time of exposure, the lower end of the specimen

holder for the CS192-53 method is bent downward so that the bottom

inch of the specimen is in a vertical plane instead of the inclined

position of the remainder of the specimen. Thus, ignition takes place

on vertically supported material, followed by the burning of material

inclined at an angle of 45 degrees. The two methods also differ in numerous details, of course, but the basic similarity is such that a comparative study appeared profitable.
-3-

The materials used in developing comparative data included about 25

textile fabrics as well as the plastic types which had been acquired.

Laboratory conditions and procedures and the techniques of sample

preparation were kept as similar as feasible in conducting tests by

the two methods. The specimens were not preconditioned other than

exposure to the laboratory atmosphere, which probably did not show

excessive variations in humidity inasmuch as nearly all of the tests were performed during the winter heating season. A general policy of

completing both types of tests on a given material the same day was

adopted. In cases where the material failed to ignite from the one second flame exposure in the CS191-53 method, application of the igniting flame was continued manually to produce ignition and provide

data for comparison.

In order to obtain comparative information also on the heat produced by

the burning specimens, a heat sensor, duplicating as nearly as feasible

that previously installed in the cabinet of the CS191-53 method (NBS

Report 8933), was provided in the cabinet of the CS192-53 method. The sensor consisted of a copper plate, 4 inches square, hung in a horizontal position above the upper end of the burning specimen and monitored

by an automatic recorder through a chrome 1-alumel thermocouple. From

the known characteristics of the plate and its increase in temperature , the heat absorbed by the plate may be calculated. For the present com- parative purpose, however, the increase in plate temperature as represented by the millivolt change in the thermocouple signal is satisfactory.

Data on the burning times and heat evolution recorded by the two methods

for 23 fabrics and 42 plastics are shown in Table 1. The values given

are, for the most part, averages from five specimens except for those

materials which did not ignite, or some specimens of which failed to

burn the full length. Such failure occurred primarily with light weight

plastics which melted easily and provided little fuel to support a flame. There was perhaps a slightly greater tendency toward this

behavior in the CS192-53 tester than in the CS191-53 equipment.

CS192-53 requires that the average burning rate of the plastic shall not

exceed 1.2 in. /sec., which corresponds to a time of 5 seconds for the

6 inch length involved. In CS191-53 an average burning time of less

than 4 seconds is defined as rapid and intense burning for textiles,

and in the Flammable Fabrics Act that limit is lowered to 3.5 seconds

for smooth -surfaced textiles. Referring to ITable 1, or the graphical

presentation shown in Figure 1, it will be noted that, on the basis of

their present limits, the two standards would agree closely on the ma- terials of either type which would be classed as unacceptable, differing

only on one plastic material. The variance is somewhat increased if the

limit stipulated by the Flammable Fabrics Act for smooth-surfaced textiles

is used as the criterion. Of considerably greater interest than the
-4-

particular acceptance limits used, however, is the generally linear

relation between the results obtained by the two methods, especially

for the plastic materials. When the data are reduced to as nearly

comparable a basis as possible by taking account of both the ignition

and the burning time, and the difference in specimen length in the two

methods, the linearity even approaches very closely a one to one ratio

as shown in Figure 2. Figure 3 graphically presents the relative heat

output obtained in the two test methods, and again the relation is

generally linear and approaches a one to one ratio.

The similarity in the comparative results obtained for plastics and for

fabrics suggested that the two types of materials might also show a re- semblance in the relations between heat output, material weight, and

burning time. Accordingly, approximate weights of the plastic materials

were determined and plots of material weight versus heat output and

material weight versus burning time (Figures 4 and 5) were made. Plots

of these same relationships for fabrics were presented in NBS Report

No. 8933. Although the plastics plot of heat output versus material

weight showed rather more scatter than that for fabrics, the relationships generally were quite similar for the two types of materials. In

the plot of burning time against material weight, it is interesting

to note the position of the present acceptance limits for fabrics,

and the possible additional criterion outlined in Report No. 8933,

with relation to the plastics materials. Application of any of these

fabrics criteria would evidently bar from use in wearing apparel, very

few of the plastic materials tested.

4. FEASIBILITY OF COMBINING TEST METHODS

The results of the comparative survey appear to support rather strongly

the suggestion that the same test method might well serve for both textile and plastic clothing materials. Inasmuch as the method described

in CS191-53 is the less complicated of the two, the ease of adapting

that equipment to general plastics testing was considered. In making

the present tests the chief difficulty experienced in using the textile

test equipment for plastics work resulted from the excessive corrosion

produced by the products of combustion of the plastics. The thread

guides in particular, soon became so rough from corrosion that the

thread caught on them after it had burned through and did not permit

the weight to fall. Slipping a thin teflon sleeving onto the guides

eliminated the trouble, however, and a teflon coating could presumably

serve as a general solution. It was found also that after repeated

exposure to the corrosive fumes, the thread stored on the spool became

noticeably weakened. It would evidently be necessary to remove the

thread supply from the cabinet when much plastics testing was to be

done. Corrosion of unprotected metal parts was extensive in both

cabinets, and the plastics equipment of CS192-53 was poorly protected,

but other instances of actual interference in the conduct of the test

did not develop during the period of this study. It should be noted that

the conditioning requirements of the CS191-53 method would need to
-5-

be modified for plastic materials, inasmuch as many plastic films

soften or melt at 105 C. In view of the generally low moisture

absorption by plastics, it is quite possible that no special con- ditioning of the specimens would be necessary.

With the minor modifications outlined above, the textile test equipment

and procedure of CS191-53 would appear to be as suitable for evaluating

the flammability of plastic materials for clothing purposes as the

flammability test of CS192-53. We would recommend, therefore, that

reference to CS192-53 be dropped from the Federal law and that all

clothing materials be evaluated by the method described in CS191-53

(with the tester modified as outlined above). We further suggest

that the 4-second maximum time limit for flame spread of CS191-53

should serve satisfactorily for the classification of plastic

materials

5. COMPARISON OF INCLINED METHOD WITH A VERTICAL METHOD

In the methods of both CS191-53 and CS192-53, and also that of N.F.P.A.

Standard 702 which has been suggested for reference in the Federal law,

the specimen is supported in an inclined position. The inclined position generally provides a better defined flame front than the vertical

position and permits more reproducible measurement on small samples,

but there has been some feeling that a vertical test position would be

preferable for wearing apparel, as better representing the conditions

of use. It appeared that some comparative data on fabrics tested in the

two positions would be of interest and the British "Vertical Strip Test"

for flammability (British Standard 2963:1958) offered a suitable

established vertical method. Briefly, the method determines the rate

of burning from visual observation of the time required for the flame

front to travel up 50 inches of a vertically suspended specimen 72

inches long and 1 1/2 inches wide. The source of ignition is a 1 1/2

inch luminous Bunsen flame, and 10 inches of the specimen burn before

timing is begun.

About 20 fabric and 15 plastic materials were tested by this British

vertical strip method. The specimens were not preconditioned in

other than the ambient room atmosphere. All of the fabrics were tested

during the cold weather heating season but, because of the production of

excessive smoke and fumes, the plastics tests were made in another

laboratory not heated at the time. To explore the effect of specimen

width on the burning rate, tests were made on both 1 1/2 inch and 3

inch strips of most of the materials, using three specimens of each

width. Table 2 shows the average time of flame travel up the 50 inch

length, recorded for the various materials. The specified criterion of

"the lower edge of the flame" was definite and satisfactory for the

cotton, rayon, and silk fabrics, but it became indeterminate and un- satisfactory for many of the synthetic fabrics and plastics. Some of
- 6

-

these formed long, charred ropes on which reduced flaming continued

over the full length. On Others the softening and stretching characteristic of heated plastic materials changed the position of the flame site

so erratically that there was often no discernable "front", or dropped

the flaming portion away from the specimen entirely. Hence, for the

plastics generally, and to a lesser extent for the synthetic fabrics,

the recorded values represent only the judgment of the operator as

to a reasonable measure of the flame progress. The effect of increasing

the specimen width was a generally consistent increase in the rate of

burning, with the major exception of one polyethylene material. The

3 inch specimens usually required around 20-30% less time to burn the

50 inches than the 1 1/2 inch specimens, but the difference tended to

be smaller among the slow burning materials and somewhat larger among

the rapid-burning materials. Although the 3 inch specimens burned more rapidly than the narrower strips, the tendency to maintain flame travel up the full length of the specimen did not appear significantly

increased

.

To permit some comparison between the results of the British vertical

test and those of the inclined methods, the results of all four methods

were reduced to a rate of flame spread basis and are listed in Table 3.

The rates in the vertical test were calculated from the values obtained

for the 1 1/2 inch wide specimens. In addition to the position of the

specimen, other differences among the methods would tend to produce the

most rapid burning rate in the vertical test. All three of the inclined

methods use small specimens and time the flame spread from the moment of

ignition, whereas the vertical method does not begin the timing until

ignition is well established and the flame travel has reached essen

tially its maximum rate. In the methods of both CS191-53 and CS192-53

the igniting flame is applied to the surface of the specimen, and in

the results shown for CS191-53 the time required for ignition is included in the calculation of the rate. While the CS192-53 method

provides separate records of the ignition time and the time of flame

travel, in practice the flame spread timing frequently starts before

ignition is well established and in this method also ,the burning time

may include part of the ignition time. The N.F.P.A. 702 method uses

edge ignition of the lower end of the specimen and therefore approaches

the conditions of the vertical test a little more closely, but again

the ignition is included in the recorded time interval.

For the cottons and rayons the rate of flame spread showed a fairly

consistent inverse relation to the weight of the material, particularly with the methods using edge ignition of the specimen. The

relation did not hold as well for synthetic and plastics materials

which are notably erratic in burning behavior. A number of the plas

tics which burned in the inclined position failed to give a reading

in the vertical position.
Figures 6 and 7 show graphically the relation between the rate of flame

spread in the vertical position and that indicated by the two commercial

standards, which followed each'other closely in most instances. It is

a generally linear relation, particularly for the cotton and rayon group

of materials. As would be expected, the correlation between the rates

determined by N.F.P.A. Standard 702 and the vertical test, shown in

Figure 8, is somewhat closer than that between the commercial standards

and the vertical.

6. EFFECT OF SEAMS ON BURNING BEHAVIOR

Among the synthetic and plastic materials a considerable number failed

to give readings in one or more of the test methods because the characteristic tendency to melt blocked flame travel, either by dropping the

burning portion away from the specimen entirely or by the softened ma- terial contracting to form a heavy rolled edge too massive to be heated

sufficiently by the flame to maintain propagation. In clothing, however,

seams or decorative stitching of cotton thread might serve as a tie

between burning and unburned material and provide a path by which flame

spread could continue. To explore this possibility, specimens of a number

of materials were prepared with a lengthwise center line of cotton

thread, either hand sewn with double thread or machine stitched. There

appeared to be no consistent difference between the effects of hand

sewing and machine stitching. The results of comparative tests con- ducted in the testing equipment of CS191-53 are summarized in Table 4.

The materials were selected to include three groups, the type all speci- mens of which regularly failed to burn, the type some specimens of which

burned and others failed, and the type all specimens of which regularly

burned the full length.

Among the synthetic fabrics the stitching clearly encouraged burning to

the top of the specimen but did not make burning a certainty. On the

materials which burned (either regularly or occasionally) without the

stitching, it did not serve as a path for more rapid flame spread, but

rather tended to retard flame travel a little on the faster-burning

materials. In the inclined test, the stitching appeared to have little

effect on the results obtained with the plastic films. Further tests made

with the vertical method indicated that, in that position, stitching up

the center of the specimen would encourage full length burning of a few

plastic films, but again it made the flame travel neither certain nor appreciably more rapid. Hence, it would not appear that seams or stitching

are a particularly significant factor in the flammability hazard of

clothing, although in a few instances they may permit some extension

of the flame spread.

7. TESTING OF COSTUME ITEMS

One area of wearing apparel in which synthetic and plastic materials of

various types are particularly prominent is that of special costume items

such as hula skirts, masquerade outfits, masks, etc. These items present
- 8 -

a special problem in that it is often impossible to cut standard-sized

test specimens from them. For hula skirts, artificial hair and other

items composed of narrow but generally flexible strips of material, preparation of a reasonably standard-sized specimen requires only that a suitable cross support be provided on the specimen holder. A specimen

of narrow strips made up to the thickness in which they are worn (or

various thicknesses in which they are worn) can be laid on such a support and tested in the usual manner. A test proposed for inclusion

in the revision of CS191-53, provides for a cross grid made of strips

of the material under test, and this avoids the introduction of any other

material into the test. A grid made of the No. 50 sewing thread, however,

would provide a more widely applicable and more easily prepared standard support. Six cross threads about an inch apart would appear

generally adequate, and would contribute no significant fuel or flame

spread to the test results. The threads could be easily positioned by

lines drawn across the lower plate of the specimen holder or by notches

in its sides. Such a standard thread grid could also serve to support

narrow trimmings and other narrow specimens, without resorting to various special arrangements.

There are some costume items, however, particularly headgear, face

masks, false noses, and the like, which may be formed quite rigidly

into strange and uncooperative shapes, and these present a more difficult test problem. In an effort to find a procedure which would

readily encompass such oddities, several different approaches were considered and briefly explored. These included ignition by timedburning tablets, ignition of the complete mask supported on an asbestos "head", and various ways of flattening the item into approximately

sheet form. None of the several procedures tried appeared to offer

sufficient advantage to warrant a shift to an entirely different test

method for so small a segment of the wearing apparel field. The judgment of the operator will unavoidably play a part in the testing of such

widely diverse items by any method, and channeling it primarily into

the selection and preparation of the specimen might well give the

greatest uniformity. Many masks will permit cutting at least one fairly

flat, standard-sized specimen, and from others a somewhat narrower

flat specimen might be obtained and supported in the same way as other narrow materials. Presumably, the testing of rigidly odd-shaped

items will be limited, and we would suggest that the standard procedure be

retained (except for the oven conditioning) , with the specimens prepared

as nearly in accordance with the standard requirements as feasible.

8 . SUMMARY

A review of the technical basis of the Flammable Fabrics Act has been

continued with work on the testing of plastic materials. A group of

about 45 plastic film and plastic coated and combination materials have

been subjected to both the flammability test of CS192-53 for "General

Purpose Vinyl Film" and that of CS191-53 for the "Flammability of Clothing
-9-

Textiles". The results of these tests indicate that, with slight modifications, the equipment and procedure specified for textiles in CS191-53

would be quite as satisfactory for plastics as the test method described

in CS192-53, and would offer significant technical advantage.

To explore the relation between the vertical burning rate of a material

and that of the material supported at an angle of 45 degrees, a representative group of the materials under study (both plastics and textiles) were tested by the vertical strip test of British Standard 2963:1958.

The cottons and rayons showed a clearly linear relation between the

burning rates in the two positions, with the vertical burning rates the more rapid. The rates calculated for the synthetic and plastic materials

also showed a generally linear relation, but the vertical burning times were highly questionable because of the particularly erratic burning

behavior of plastics in the vertical position. A seam of cotton thread

up the center of the specimen did not increase the flammability hazard

significantly in either the inclined or the vertical position.

Several approaches to the problem of testing costume items and narrow

trimmings which will not provide standard-sized specimens, have been

explored. It would appear that most items of that type could be ac- comodated rather simply by providing a support gird of sewing thread across the back plate of the specimen holder. For the relatively

infrequent tests that may be required of rigidly odd-shaped masks and

the like, it is suggested that the operator prepare specimens as near

to the regulation size as feasible, for test by the standard ignition

procedure

USCOMM- NBS -DC
Table 1. Results of Flame Tests by Two Methods

Test Materials CS 19 1-53 CS192-53

Identifying designation Primary components Burn time Heat

output Ignitiontime Heat

output

Plastic Materials sec

Plastic A 3.15* 0.130 0.89 Plastic B 3.65 0.190 0.70.46 .06* Plastic C 3.48 0.77 3 . 54* Plastic D 9.81 0.245 2.65 8.67* Plastic E 3.68 0.153 0.91 3.73 Plastic F 7.52 0.207 1.52 9.88* Plastic G 1.50 Plastic H 7.73* 0.285 1.67 Plastic I 1.66 Plastic J (raincoat I) 0.86 Plastic K (raincoat II) vinyl 7.12 0.178 1.57 5.58 0.172 Plastic L (raincoat III) 13.22 (1) 0.453 1.44 6 . 12 . 70

76( 1 )

0.307

Plastic M (mattress cover) 3.62* 0.122 1.18 4.59* 0.072 Plastic N (dress) vinyl with knit cotton back 0.66 32.30* 0.140 Plastic 0 8.09* 0.189 1.14 9.76* 0.118 Plastic P 7.28* 0.172 1.14 11.60* 0.165 Apron A 7.20* 0.168 0.84 7.55* 0.148 Apron B 7.00* 0.165 0.83 8 . 12* 0.152 Polyethylene A Polymat

polyethylene 29.10 0.282 4.25

15.51 0.346 5.40 15.57 Composite A Composite B

neoprene and nylon 4.61 neoprene and cotton 4.61 Composite C. rubber and cotton 29.62 1.943 5.93 31.91

Composite C, rubber and cotton 39.29 64.92 (1) 2.085

1.697 (1 5.30 ! 42! 107

-r

4926(1)

Composite C. rubber and cotton

Composite D^ rubber and nylon

136.26

16.83

1.670

0.927

8.36

1.72

173,

23,

32 1.188

32 | 0.988 \

f

Composite rubber and nylon 11.98 0.892 1.64 16.03 0.950

Composite D„ rubber and nylon 25.63 1.486 2.37 36.20 1.639

Composite D

4 rubber and nylon 22.74 1.082 2.22 24.93 | 1.099

Composite D,. rubber and nylon 21.62 1.545 2.42 25.41 1.551

Composite D rubber and nylon 35.20 1.755 3.59 32.64 1.554

Composite E polyethylene and Fiberglas 16.07 0.626 1.46 22.39 0.528 Propionate A extruded propionate, 5 mil 7.17 0.295 2.42 13.08* 0.310 Propionate B extruded propionate, 10 mil 16.21 0.886 4.95 17.49 0.759 Vinyl A vinyl, 2 mil 3.52* 0.136 0.66 4 . 18* 0.071 Vinyl B vinyl, 4 mil 6.27 0.250 0.82 —

8.65 0.203 Vinyl C vinyl, 6 mil 11.25 0.352 1.67 i 13.76* 0.342 Vinyl D vinyl, 10 mil 17.47 0.564 2.17 19.83 0.575 Vinyl E , expanded vinyl - cotton lining 40.34 (1) 0.575(1) 1.42 I 43.30* 2.000 Vinyl E 9 (back of E^) cotton lining-expanded vinyl 37.48

59.08 (1) 1.7201.620(1) 4.25 45.63

82.02(1)

1.394

1 . 100 ( 1 ) Disposable clothing (uncoated) polyethylene 1.03 Disposable clothing (coated) polyethylene 14.74 0.313 I 0.86 ! 18.27* 0.312

One or more specimens failed to burn far enough to provide a reading; value based on less than 5 specimens (sometimes

on only one)

The flame failed to break through to the back of the burning specimens, a situation which tended

time and reduce the heat output. Where the flame broke through some specimens and not others,

types of burning were averaged separately and the two values are shown.

to extend the burning

results from the two
Table 1 (con't)

Test Materials CS191-53 CS 192-53 Identifying designation Primary components _ . 1 Heat Burn time output Ignition i Burn j Heat

time J time ! output

Textile

Net Materials

Dacron

sec

* mv sec ] sec mv

0.56 ] 7.08* | Sheer Dacron 16.85 0.209 0.58 i 20.54* 0.079

Silk I Silk 3.46 0.117 0.85 ! 4.61* 0.072

Silk II Silk 4.42 1.40 5.73 — Silk III Silk 7.39 0.128 0.87 12.78 0.104 Cotton I (organdy) Cotton 4.29 0.265 0.92 5.39 0.312 Cotton II (batiste) Cotton 9.66 1.82 7.53 Percale sheet Cotton 19.36 0.579 2.88 14.88 38.38 (1) 0.525

0.315 (1) Quilted pad Cotton 38.87 1.313 2.45 47.24 1.083 Flannelette Cotton 18.40 0.543 0.96 15.38 0.496 Shantessa print Cotton 20.03 : 0.479 1.91 25.07 0.457 Dotted Swiss Dacron 65%, cotton 35%. 11.58 j 0.429 0.81 11.78 0.382 Stretch poplin Zantrel rayon 50%., cotton 50% 29.48 , 0.857 3.11 20.86 0.701 Bengaline (warp direction) Rayon warp, cotton fill

.

35.85 ; 0.772 48.36 (1) 0.437(1] 3.93 j 60.57 (1

'

0.402 (I)

Bed blanket II Rayon 74%, cotton 20%, nylon 6% 1.12(2) j 0.64 1.45 (1 0.572 (1) Pile Fabric III Orion pile, cotton back 20.16 ’ 1.433 1 1.71 32.35 (1 0.855 (1) Quilted robe II Acetate cover and back, polyester pad 20.31 i 0.974 | 1.12 16.66 0.658 Raincoat (warp direction) Cotton warp, acetate fill 21.70 ' 0.952 j 3.21 20.22 1 0.956 Raincoat (fill direction) Cotton warp, acetate fill 49.95

49.48(1)

0.850 3.36 0.589(1) 34.94 ' 0.750

63.80(1) ; 0.600 (1) Lined lace I Cotton lace, acetate back 8.98 0.945 j 1.63 14.32 j 1.139 Lined lace II Wool 50%o, raffia 50%,, acetate back 17.79 1.191 ! 1.31 26.37 1.172 Taffeta Acetate 6.67 . 0.491 1.50 7.35 0.496 Acetate I Acetate, rayon, metallic thread 4.20 | 0.294 0.45 5.29 0.306 Acetate II Acetate 5.95 0.428 0.82 j 6.41 0.438

* One or more specimens failed to burn far enough to provide a reading; value based on less than 5 on only one)

.

specimens (sometimes

The flame failed to break through to the back of the burning specimens, a situation which tended to extend the burning

time and reduce the heat output. Where the flame broke through some specimens and not others, results from the two types of burning were averaged separately and the two values are shown.

2 The specimens showed only a surface flash or burning and the base fabric was not ignited.
Table 2 . Results from British Vertical Strip Test

Average time for 50-inch flame travel Material 1 1/2-in. width 3-in. width

sec Cotton and Rayon Textilessec

Chiffon, rayon 8.1 Cotton I, organdy 9.4 5.4 Cotton II, batiste 12.5 Novelty I, rayon 17.8 Shantessa print 16.6 11.3 Percale sheet, cotton 19.0 13.1 Flannelette, cotton 20.4 16.0 Stretch poplin 27.5 21.3 Bengaline 30.3 23.2 Quilted pad, cotton 37.1 32.5

Silk and Synthetic Textiles

Silk I 23.1 (1) 20.3 (2) Silk II 30.3 (2) Net, Dacron 78.0 (2) (3) Acetate I 25.6 21.3 Acetate II 26.7 21.6 Sheer, Dacron (3) (3) Dotted Swiss 19.3 11.5 Taffeta, acetate 29.8 27.8 Lace I 36.1 25.1 Quilted robe II, acetate 80.0 76.0 Pile fabric III, Orion pile 73.0 71.0

Plastic Sheet and Coated Materia Is

Polyethylene A 188 212 Disposable clothing (uncoated) 163 (2) 136 Disposable clothing (coated) 58 56 Plastic D — (3) 28 (1) Plastic M (mattress cover) --- (3) --- (3) Plastic 0 --- (3) --- (3) Plastic P — (3) --- (3) Vinyl A, 2 mil — (3) — (3) Vinyl B , 4 mil 35 (2) --- (3) Vinyl C, 6 mil 32 (2) 38 (2) Vinyl D, 10 mil 52 (2) 38 Propionate A, 5 mil --- (3) --- (3) Propionate B, 10 mil --- (3) — (3) Composite E (polyethylene and Fiberglas) 30 27 Vinyl E (expanded vinyl) 52 41

Value based on 2 out of 3 specimens; other failed to burn to the top.

Value based on 1 specimen only; others failed to burn to the top.

3 None of the specimens burned to the top marking wire.
Table 3. Comparative Results in Vertical and Inclined Test Methods

Rate of Flame Spread

Material

Material

weight

TFIFTsTi Vertical —ottt; 702CS 191-53C3 192-53 oz/yd2 in/sec in/ sec

i in/sec in/ sec

Cottons anfl Rayons

Rayon chiffon 1.0 6.17 2.08 1.55 1.30 Cotton I (organdy) 1.5 5.32 1.61 1.17 1.11 Cotton II (batiste) 1.8 4.00 1.39 0.52 0.80 Novelty I, rayon 3.3 2.81 0.88 Flannelette, cotton 3.7 2.45 0.71 0.27 0.39 Shantessa print 3.9 3.01 0.86 0.25 0.24 Percale sheet 3.9 2.63 0.78 0.26 0.40 (1) Stretch poplin 6.2 1.82 0.53 0.17 0.29 Bengaline 6.5 1.65 0.45 0. 10 0. 10 Quilted pad, cotton 9.6 0.31 0.13 0.13

Silks and Syntl

l

l ietic Fabrics

Silk I 0.6 2.16 1.67 1.44 1.30 Silk II 0.7 1.65 (1) 1.43 1.13 1.05 Net, Dacron 0.8 0.64 (1) 0.58 —- (2) 0.85 Sheer, Dacron 2.0 ---- (2) 0.39 0.30 0.29 Acetate I 1.7 1.95 1.39 1.18 1. 13 Acetate II 2.8 1.87 0.94 0.88 0.94 Dotted Swiss 2.8 2.59 0.89 0.43 0.51 Taffeta, acetate 3.5 1.68 0.93 0.75 0.82 Lace I 5.1 1.39 0.70 0.56 0.42 Quilted robe II 6.8 0.62 0.42 0.25 0.36 Pile fabric III 9.2 0.68 0.35 0.25 0. 19

Plastic Sheet and Cboated Mater: als

Polyethylene A 4.1 0.27 0.17 —- (2) Disposable clothing (uncoated) 1.3 0.31 (1) —- (2) —- (2) Disposable clothing (coated) 1.8 0.86 0.34 0.33 Plastic D 3.9 1.79 (3) 0.51 0.69 Plastic M (mattress cover) 1.7 —- (2) 1.38 1.31

Plastic 0 3.7 —- (2) 0.62 0.61 Plastic P 4.1 —- (2) 0.69 0.52 Vinyl A, 2 mil 1.6 —- (2) 1.42 1.44 Vinyl B, 4 mil 3.5 1.43 0.80 0.69

Vinyl C, 6 mil 5.7 1.56 0.44 0.44 Vinyl D, 10 mil 9.4 0.96 0.28 0.30

Propionate A, 5 mil 4.7 --- (2) 0.70 0.46

Propionate B, 10 mil 9.1 ---- (2) 0.31 0.34

Composite E 3.4 1.67 0.31 0.27

Vinyl E (expanded vinyl) 17.9 0.96 0.12 0.13

Based on results for 1 or 2 specimens only.

2 None of the specimens burned to the top.

3 Calculated from the results for two 3-inch specimens since none of the 1 1/2-inch specimens burned to the top.
Table 4. Effects of Stitching on the Results

Obtained by the CS191-53 Method

Without stitching With stitching

No. of specimens Avg. No. of specimens Avg.

Material tested burned time tested burned time

Pink nylon net 5 0

sec

11 11

sec 7.56

Yellow nylon net 5 0 — 6 6 7.68

Red nylon chiffon 5 0 15 13 9.29

Green nylon chiffon 3 0 — 2 2 10.78

Dacron net 10 5 7.15 12 10 5.16

Nylon-rayon scarf 5 2 5.13 5 5 6.36

Silk chiffon 3 3 4.15 3 3 4.40

Green sheer 4 4 4.14 3 3 4.72

Plastic B 3 3 2.82 3

' 3 3.32

Plastic C 3 3 3.26 3 3 3 . 14

Plastic G 5 0 — 5 0 —

Plastic H 5 2 7.73 5 1 8.53

Plastic I 5 0 — £ , 0 ----
Fig. 1. Relation Between Burning Times by the Two Methods
CSI92-53

SPECIFIC

BURNING

TIME,

SEC.

/IN.

CSI9I-53 SPECIFIC BURNING TIME, SEC. /IN.

(WITH FORCED IGNITION)

Fig. 2. Relation Between Specific Burning Times by the Two Methods
HEAT

RECORDED,

MILLIVOLTS,

CS

192-53

Fig. 3. Relation Between Heat Recorded by the Two Methods
HEAT

RECORDED,

MILLIVOLTS,

CSI91-

53

{

WITH

FORCED

IGNITION)

Fig. 4. Relation of Heat Output to Material Weight for Plastics
CS

191

-

53

BURNING

TIME,

SEC.

.(WITH

FORCED

IGNITION)
FLAME

SPREAD

RATE,

IN./SEC.(

BRITISH

VERTICAL

STRIP

METHOD)

Fig. 6. Relation Between Vertical and Inclined Burning Rates for

Cotton and Rayon Fabrics
FLAME

SPREAD

RATE,

I

N./SEC.

(BRITISH

VERTICAL

STRIP

METRO

FLAME SPREAD RATE, IN./SEC.

Relation Between Vertical and Inclined Burning Rates for

Silk and Synthetic Fabrics and Plastics

Fig. 7.
FLAME

SPREAD

RATE,

IN./SEC(

BRITISH

VERTICAL

STRIP

METHOD)

Fig. 8. Relation Between the Vertical Burning Rate and the Inclined

> Rate Determined by the N.F.P.A. 702 Method

1