NBS

PUBLICATIONS

NBSIR 84-2960

AiiioH oasaoB

Heat Release and Mass Loss Rate

Measurements for Selected

Materials

William D. Walton

William H. Twilley

U.S. DEPARTMENT OF COMMERCE

National Bureau of Standards

National Engineering Laboratory

Center for Fire Research

Gaithersburg, MD 20899

December 1984

Sponsored by:

U.S. Department of Transportation

Federal Aviation Administration

^^chnical Center

“HC ““"lantic City Airport, NJ 08405

100

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NATIONAL BUREAU

OF STANDARDS

UBRARY

NBSIR 84-2960

t HEAT RELEASE AND MASS LOSS RATE

MEASUREMENTS FOR SELECTED

MATERIALS

Oj/oo

t rr

'

William D. Walton

William H. Twilley

U S. DEPARTMENT OF COMMERCE

National Bureau of Standards

National Engineering Laboratory

Center for Fire Research

Gaithersburg, MD 20899

December 1984

Sponsored by:

U.S. Department of Transportation

Federal Aviation Administration

Technical Center

Atlantic City Airport, NJ 08405

U.S. DEPARTMENT OF COMMERCE, Malcolm Baldrige, Secretary

NATIONAL BUREAU OF STANDARDS, Ernest Ambler, Director

TABLE OF CONTENTS

Page

LIST OF TABLES iv

LIST OF FIGURES v

NOMENCLATURE vii

Abstract 1

1. INTRODUCTION 1

2. DESCRIPTION OF EXPERIMENTAL APPARATUS 2

3. NON-FLAMING EXPERIMENTS 5

4. FLAMING EXPERIMENTS 6

5. ANALYSES OF TEST RESULTS 9

6. ACKNOWLEDGMENTS 12

7. REFERENCES 12

-ill-
LIST OF TABLES

Page

Table 1. Description of materials

Table 2. Average mass loss rate for non-f laming experiments 15

Table 3. Heat of gasification 16

Table 4. Time to Ignite 17

Table 5. Effective heat of combustion and stoichiometric ratio .... 18

-Iv-
LIST OF FIGURES

Page

Figure 1. Dimensional view of calorimeter - see figure 2 for

section A-A

Figure 2, Sectional view A-A of calorimeter 20

Figure 3. Mass loss rate for particle board, non-flaming 21

Figure 4. Mass loss rate for PMMA, non-flaming 22

Figure 5. Mass loss rate for rigid foam, non-flaming 23

Figure 6. Mass loss rate for carpet, non-flaming 24

Figure 7. Mass loss rate for aircraft panel, non-flaming 25

Figure 8. Average mass loss rate for particle board, non-flaming 26

Figure 9. Average mass loss rate for PMMA, non-flaming 27

Figure 10. Average mass loss rate for rigid foam, non-flaming 28

Figure 11. Average mass loss rate for carpet, non-flaming 29

Figure 12. Average mass loss rate for aircraft panel, non-flaming 30

Figure 13. Time to ignite for particle board 31

Figure 14. Time to ignite for PMMA 32

Figure 15. Time to ignite for rigid foam 33

Figure 16. Time to ignite for flexible foam 34

Figure 17 . Time to ignite for carpet 35

Figure 18. Time to ignite for aircraft panel 36

Figure 19. Heat release rate for particle board 37

Figure 20. Mass loss rate for particle board 38

Figure 21 . Total heat released for particle board 39

Figure 22. Heat release rate for PMMA 40

Figure 23. Mass loss rate for PMMA 41

Figure 24. Total heat released for PMMA 42

-V-
Figure 25. Heat release rate for rigid foam ^3

Figure 26. Mass loss rate for rigid foam

Figure 27. Total heat released for rigid foam ^3

Figure 28. Heat release rate for flexible foam

Figure 29. Mass loss rate for flexible foam ^7

Figure 30. Total heat released for flexible foam ^8

Figure 31. Heat release rate for carpet

Figure 32. Mass loss rate for carpet 30

Figure 33. Total heat released for carpet 31

Figure 34. Heat release rate for aircraft panel 32

Figure 35. Mass loss rate for aircraft panel 33

Figure 36. Total heat released for aircraft panel 34

-vi-
NOMENCLATURE

^ effective heat of combustion

L heat of gasification

m mass

An change in mass

q heat transfer

Q energy release

r stoichiometric oxygen/ fuel ratio

Subscripts

b burning

Superscripts

()" per unit area

(*) per unit time

-vii-
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M
HEAT RELEASE AND MASS LOSS RATE MEASUREMENTS FOR SELECTED MATERIAI.S

William D. Walton

William H. Twilley

Abstract

The purpose of this study was to measure fire parameters for a selected

group of materials. These parameters are to be used in a continuing study of

flame spread. The parameters measured are rate of heat release, rate of mass

loss, heat of gasification, effective heat of combustion, stoichiometric ratio

and time to ignite. Heat release rates and mass loss rates are given as a

function of time for several external heat flux levels. The rate of heat

release is also given as a fxinction of the total beat released. The experimental results and analysis are shown for six diverse materials representative

of aircraft (interior panels, carpeting, and seat cushions) and buildings

(particle board, polymethyl methacrylate (PMMA) and rigid foam).

Key words: rate of heat release, ignition, fire tests, fire safety,

aircraft interior materials.

1 . INTRODUCTION

A variety of fire parameters have been considered important in predicting

the fire performance of materials in full scale fires. Quintiere [1] has

assessed the importance of a number of these parameters and developed relationships for use in predicting flame spread. In addition, flame spread

measurements have been conducted for a selected group of materials (2). This

paper reports measurements of fire parameters conducted on the same group of

- 1 -
materials, as part of a continuing effort to predict full-scale fire performance from laboratory measurements. The six materials tested are particle

board, polymethyl methacrylate (PMMA) , rigid foam, flexible foam, carpet and

aircraft panel. A description of the materials can be found in table 1 [2]

A series of non-flaming and flaming experiments were conducted in a heat

release rate calorimeter to determine the fire parameters. The fire parameters that were measured are rate of heat release (Q), rate of mass loss (m)

,

heat of gasification (L) , effective heat of combustion (AH), and stoichiometric ratio (r) and time to ignite. Terminology relating to fire is not

always standardized and several of the parameters mentioned above may be

described by different names. Rate of heat release may also be called rate of

energy release. The effective heat of combustion may be referred to as heat

of combustion or heat of reaction. The term effective is used to signify the

heat of combustion during actual fire conditions as opposed to the maximum

theoretical value.

2. DESCRIPTION OF EXPERIMENTAL APPARATUS

A detailed description of the experimental apparatus, known as the NBS II

calorimeter, has previously been reported [3]. In brief, the apparatus

consists of a steel box with dimensions of approximately one meter on each

side. The top of the box opens to a 0.46 m diameter exhaust stack which vents

to the outside of the test building. The bottom of the box has an opening to

permit the Insertion of a calibration burner or a sample holder. When either

is in place the box is fully enclosed. Air is Introduced into the apparatus

through a controlled, fan powered air dilution line and distributed through

-2-
air cooling towers. Energy is supplied to the test specimen through premixed

air - natural gas radiant panels located around the specimen on the 'cui sides

of the box. These are capable of providing irradiance levels from approximately 25 to 80 kW/m^. Lower irradiances may be obtained through the use '

shades. One half of the radiant panels can be operated to irradiate a single

side of a vertical specimen or all panels can be operated to irradiate both

sides of a vertical sample or the top face of a horizontal specimen.

Specimens in either the vertical or horizontal position can be weighed continuously with an electronic weigh cell. Diagrams of the apparatus are shown in

figures 1-2.

Several modifications were made to the apparatus and associated

instrumentation for this experimental series. The calorimeter was originally

designed to measure rate of heat release using a substitution burner. For

this method a gas fired substitution burner is connected via a feedback

control system to a grid of thermocouples in the exhaust stack. As the

specimen releases heat the gas flow to phe substitution is reduced such that

the temperature as measured by the thermocouple grid remains constant. The

reduction in gas flow is directly related to the rate of heat release. For

this test series it was decided to use the oxygen consumption technique to

determine the rate of heat release. This technique has been successfully used

in a number of applications [4,5], and overcomes some of the problems of the

substitution burner method such as thermal transients when the sample is

inserted into the test chamber.

A detailed explanation of the oxygen consumption technique can be found

in ref. [6]. It is based on the concept that, to a reasonable engineering

- 3 -
approximation, the heat produced per unit mass of oxygen consumed is nearly

constant for materials commonly used in construction [7]. Reference [6]

describes a number of possible measurement options which can be used to implement the oxygen consumption technique. For the NBS II calorimeter total air

flow into the system was measured. The concentrations of O

2

, CO

2

and CO in

the stack were measured with water vapor trapped out. The gas concentrations

as well as all other data were collected on a digital data acquisition system

at a 5 second interval and processed with a computer data reduction program.

The normal vertical specimen holder used in the apparatus was

reconstructed to accommodate back-to-back vertical specimens with a total

exposed area of 0.1515 m , Two total heat flux gauges were installed in the

plane of the specimen adjacent to the specimen holder. One of these gauges

faced in the direction of each of the sample faces. The gauges were calibrated with a gauge mounted in the face of a blank specimen. This allowed a

measurement of the incident heat flux to the specimen to be made prior to each

experiment. A similar arrangement with a single heat flux gauge was used for

the horizontal specimens. The exposed area of the horizontal specimen was

0.0465 m^.

An air-acetylene pilot was used to ignite the specimens in the flaming

experiments. For vertical specimens the pilot was in the plane of the

specimen approximately one centimeter above the specimen holder. In this

position the pilot would ignite the combustible gas from the specimen but

would not impose a heat flux on it. If back-to-back specimens were used a

pilot was placed over each of the specimens. For horizontal specimens a

single pilot was placed perpendicular to each of the specimens and approximately two centimeters above the specimen surface.

-4 -
3 . NON-FLAMING EXPERIMENTS

The purpose of the non-flaming experiments was to determine the external

heat flux required to generate a unit mass of vapors. This can be defined as

a heat of gasification (L). Mass loss data for determining heat of

gasification should preferably be taken with the surface bathed in an inert

atmosphere such as nitrogen. This prevents oxidation and thus heat release at

the material surface during the experiment. The use of an inert atmosphere

was not practical in the experimental apparatus used. Care was taken however,

to attempt to exclude data in the analysis during the time at which a specimen

was glowing or flaming. Figures 3-7 are the characteristic mass loss rate

data for the materials. To simplify presentation, data for experiments with

approximately the same irradiance have been shown as a single curve. An error

bar has been used to indicate the average range of the data contributing to a

single curve. Data was collected until the specimen fell from the holder.

Data for the flexible foam could not be taken in this apparatus because of

excessive melting and dripping.

All experiments, except the aircraft panel, were conducted on back-toback vertical specimens irradiated from both sides. The aircraft panel was

mounted vertically and exposed on a single side. The carpet specimens were

held in place with 19 gauge (1.04 mm), 1/2 x 1/2 inch (13 x 13 mm) mesh galvanized hardware cloth placed over the specimen face. A 1/2 inch (13 tun) thick

calciijm silicate board was placed between the specimens to maintain rigidity.

All specimens were conditioned at 55% relative humidity and a temperature of

22°C.

-5 -
The heat of gasification has been used previously as both a time

dependent and average parameter. For the data collected here it was decided

to use an average value. Table 2 shows the values of external heat flux or

irradiance and the average mass loss rate per unit area. In addition, the

percent of the peak mass loss rate over which the average mass loss rates were

computed is shown. The percentages were chosen to describe an average peak

mass loss rate in a systematic manner. Figures 8-12 are the data in table 2,

plotted with a least squares linear fit. The slope of the line has been

defined as the heat of gasification. These values along with the intercept

are shown in table 3. It should be noted that insufficient data were

available for the PMMA to have confidence in the curve fit.

4. FLAMING EXPERIMENTS

This group of experiments was designed to measure the time to ignition,

the rate of heat release and mass loss, the effective heat of combustion, and

the stoichiometric ratio. The time to ignition was measured in the same

experiments as the other fire parameters. The ignition data were taken to

compare with ignition times measured previously in another apparatus on the

same materials [2]. The ignition time was measured by visual observation and

defined as the time at which flames were sustained over the surface. The

observed ignition times at various external heat flux levels are listed in

table 4. The data have also been plotted along with the data previously taken

in figures 13-18. The number of experiments with ignition times reported is

larger than the number of experiments described in other parts of this

section. This is a result of instrument failure which affected the calculations of the other fire parameters but did not Interfere with the observation

of ignition time.

-6 -
The rate of heat release measurements were made using the oxygen

consumption technique which was described earlier. Since the gas fired

radiant panels used to irradiate the specimen release heat, a correction was

required. Prior to each experiment a baseline heat release rate was established for the radiant panels and subtracted from the subsequent measurements

for the specimen. This procedure was handled automatically through the

computer data reduction program. The magnitude of the heat release from the

panels was significant and in many cases greater than the heat released by the

specimen. In the apparatus, the heat release from the radiant panels at the

25, 50 and 75 kW/m^ incident flux levels to the specimen was approximately

280, 450 and 600 kW/m , respectively. These baseline levels must be

considered when analyzing the results of the experiments.

In order to provide the highest level of confidence practical in the

experimental results a number of calibration procedures were used. Prior to

conducting the experiments, the individual instruments were calibrated and

checked over a period of time for drift, A number of experiments were

conducted in which the heat release of a metered quantity of technical grade

methane was measured. After calibration, the measured heat release corresponded to the value calculated by the oxygen consumption technique to within

± 5%. Each day prior to conducting heat release measurements, a methane

calibration test was conducted as a check of instrumentation. For each experiment in which the heat release was measured the mass of the sample was also

measured. Since the density of materials varied widely, the electronic weigh

cell was adjusted and calibrated each time a different series of specimen

materials were tested.

-7 -
Figures 19-36 are the characteristic curves of the heat release and mass

loss rate measurements grouped by material. In these curves, rates for experiments with approximately the same irradiance have been shown as a single

curve with an error bar to indicate the average variation. The heat release

data have been shown both as a function of time and of total heat released.

The latter is one method of describing release rates at different irradiance

levels without the effects of ignition delay times. The data shown in all

curves is over the time in which the specimen remained intact and in the

sample holder. All experiments, except the flexible foam, were conducted on

back-to-back vertical specimens irradiated from both sides. The flexible foam

specimens were mounted horizontally and irradiated from the top only. The

carpet specimens were held in place with 19 gauge (1.04 mm) , 1/2 x 1/2 inch

(13 X 13 mm) mesh, galvanized hardware cloth placed over the specimen face, A

1/2 inch (13 mm) thick calcium silicate board was placed between the carpet

specimens to maintain rigidity.

The rate of heat release measurements were used to calculate the

effective heat of combustion and the stoichiometric ratio. The effective heat

of combustion, which is sometimes referred to as the heat of reaction, can be

defined as either a time dependent or average parameter. As a time dependent

parameter

AH

Q is the rate of heat release and m, is the rate of mass loss for the burning

D material. Both of these values are time dependent and thus the effective heat

of combustion may vary with time. For most applications an average effective

heat of combustion is desired and can be defined as

-8 -
Q"

where Q is the heat released and is the change in mass during the time

over which that heat was released. From the effective heat of combustion the

stoichiometric oxygen/fuel mass ratio r can be computed as

^ AH (MJ/kg)

^ 13.1 (MJ/kg)

where 13.1 (MJ/kg) is the heat produced per unit mass of oxygen consumed, a

constant for all materials [7]. Table 5 shows the effective heat of combustion and stoichiometric ratio for the materials at various irradiance levels.

Also given are the average values of these quantities for each material.

5. ANALYSES OF TEST RESULTS

Very little data, of the type measured, is available for the materials

tested with the exception of the PMMA and the rigid foam. In fact several of

the materials are unique and no data for these are known to exist. The curves

for the non-flaming experiments show that the materials demonstrate a number

of different mass loss profiles. The particle board shows a single rise and a

gradual decline. The rigid foam carpet and aircraft panel show two peaks

indicating that lighter fractions of the material may be released quickly.

The PMMA demonstrates a nearly constant rise in rate and at the higher

irradiance levels appeared to boil on the surface.

The heat of gasification measurements for particle board, PMMA and rigid

foam can be compared to the data of Tewarson [8]. He has measured fire para-

-9-
meters for oak, PMMA and rigid foam. Data for the rigid foam can also be

found in [7] much of which was measured by Tewarson, The rigid foam tested by

Tewarson is reported to be the same as that tested in this study. The heat of

gasification values from Tewarson were determined from measurements at a

single irradiance. Tewarson' s measurements of heat of gasification for oak is

1.7 MJ/kg for an irradiance less than or equal to 46 kW/m^ and 5.5 MJ/kg for

a an irradiance above 46 kW/m^. Although oak is quite a different material from

particle board, these values span the average value of 4.52 MJ/kg determined

for particle board. Tewarson reports a value of 1.63 MJ/kg for PMMA as

compared to the 1.81 MJ/kg measured here. These are within the expected

agreement but the values for the rigid foam are not. Tewarson reports

3.11 MJ/kg and this study 7.77 MJ/kg. Since the results for the rigid foam

are the most consistent, they indicate that the rigid foam used in this study

may not be the same as that tested by Tewarson.

The ignition data in figures 13-18 shows good agreement between the time

to ignite measured in the NBS II calorimeter and flame spread apparatus.

There seems to be a trend for NBS II times to be slightly shorter. This may

be a result of the different airflow characteristics in the two pieces of

apparatus

The heat release and mass loss curves reveal several attributes of the

materials and test apparatus. Those heat release curves which do not go to

approximately zero, such as the particle board and PMMA, indicate the experiments were terminated prior to complete consumption of the material. Those

materials fell from the sample holder and the test was terminated at that

point. The total heat released versus heat release rate curves for rigid

- 10-
foam, flexible foam and carpet indicate that at the higher irradiances the

total heat released is almost independent of irradiance. It can also be

observed that the mass loss curves correspond well with the heat release

curves. The exception to this is for PMMA. The mass loss curves show an

intermediate peak at all irradiance levels. This peak appears to correspond

to the delamination of the two sheets of PMMA that were glued together to form

the specimen. This peak is only barely visible in the heat release curves.

It can also be seen for the PMMA that the mass loss and heat release rates

were continuing to rise after the test was terminated. Sample delamination

resulted in the specimen falling from the holder before a substantial portion

of the sample had been consumed. As a result, neither a peak nor a steadystate value could be obtained.

As with the heat of gasification there is only limited data for effective

heat of combustion and stoichiometric ratio with which to compare. Since the

stoichiometric ratio was derived from the effective heat of combustion the

comparison need only be made with one of these parameters. The effective heat

of combustion data from Tewarson for oak ranges from 11.2 - 12.6 MJ/kg. This

compares with an average 11.6 MJ/kg measured for particle board (table 5).

Tewarson' s values for PMMA range from 23.9-24.9 MJ/kg with a maximum value

measured in the oxygen bomb calorimeter of 25.2 MJ/kg. These compare well

with the values at an irradiance level of approximately 50 kW/m but the

values at other levels exceed the maximum theoretical value. This may be due

in part to the relatively short time of the PMMA experiments and the

delamination of the samples. The average effective heat of combustion

measured for the rigid foam was 19.0 MJ/kg. The oxygen bomb value as reported

by Tewarson was 25.0 MJ/kg and he measured effective heats of combustion from

- 11 -
10.8-15.0 MJ/kg. As with the heat of gasification there is considerable

difference between the results of this study and those from Tewarson.

It is generally assumed that the effective heat of combustion is

basically independent of irradiance level. This was found to be true for all

materials except the aircraft panel. It showed a strong dependence of irradiance level on effective heat of combustion. This may be due to the fact the

material is a composite and does not burn well at lower irradiance levels. As

a result the heat of combustion measurement may show the effect of different

materials burning at different Irradiance levels.

6. ACKNOWLEDGMENTS

The authors wish to acknowledge the technical advice of Dr, James

Quintiere and Mr. William Parker and the assistance of Ms. Margaret Harkleroad

in the preparation of this report. In addition, the authors wish to acknowledge Dr. T. Eklund of the Federal Aviation Administration Technical Center for

his support as technical monitor for this study.

7 . REFERENCES

[1] Quintiere, J.G, , An Assessment of Correlations Between Laboratory and

Full-Scale Experiments for the FAA Aircraft Fire Safety Program,

Part 2; Rate of Energy Release in Fire, Nat, Bur. Stand. (U.S.)

NBSIR 82-2536 (1982).

[2] Harkleroad, M. , Quintiere, J. and Walton, W., Radiative Ignition and

Opposed Flow Flame Spread Measurements on Materials, Federal Aviation

Administration, DOT/FAA/CT-83/28 (1983).

[3] Tordella, J. and Twilley, W.H., Development of a Calorimeter for

Simultaneously Measuring Heat Release and Mass Loss Rates, Nat. Bur.

Stand. (U.S.) NBSIR 83-2708 (1983).

- 12-
[4] Babrauskas, V., Lawson, J.R. , Walton, W.D. and Twilley, W.H.

,

Upholstered Furniture Heat Release Rates Measured with a Furniture

Calorimeter, Nat. Bur, Stand. (U.S.) NBSIR 82-2604 (1982).

[5] Babrauskas, V., Development of the Cone Calorimeter — A Bench-Scale

Heat Release Rate Apparatus Based on Oxygen Consumption, Nat. Bur.

Stand. (U.S.) NBSIR 82-2611 (1982).

[6] Parker, W.J., Calculations of the Heat Release Rate by Oxygen

Consumption for Various Applications, Nat. Bur. Stand. (U.S.)

NBSIR 81-2427-1 (1982).

[7] Huggett, C. , Estimation of Rate of Heat Release by Means of Oxygen

Consumption Measurements, Fire and Materials, Vol. 4, No. 2, 61-65

(1980).

[8] Tewarson, A., Physics - Chemical and Combustion/Pyrolysis Properties of

Polymeric Material, Nat. Bur. Stand. (U.S.) NBS-GCR-80-295 (1980).

[9] Materials Bank Compendixim of Fire Property Data, Products Research

Committee (1980).

- 13-
Table 1. Description of materials

Material Description Thickness (cm)

Particle board Douglas Fir wood with particle

size range of 0.97-2.6 mm and

ureaformaldehyde binder

Poly (methyl methacrylate)

[PMMA]

Rigid foam

Rohm & Haas* - T3rpe G, two

0.635 cm thick samples bonded

with methyl ethyl ketone

Polyurethane low density rigid

foam - GM 3l”^

Flexible foam Polyurethane low density flexible

foam - Custom Products, Inc.*

HD54CA low density

Carpet Wool-nylon looped fibers with a rubberized backing

Aircraft panel Aircraft interior lining (#2), a composite material consisting of a phenolic-polyamide honeycomb core with apoxy flberlte face sheets

and a tedlar coating on the exposed

face

1.28

1.28

2.54

2.54

0.634

2.54

* Use of trade names Implies no endorsement by the National Bureau of Standards.

GM 31 Is a material from the Material Bank of the Product Research Committee

currently maintained at the National Bureau of Standards ("Materials Bank

Compendiiim of Fire Property Data", Product Research Committee, February 1980).

14 r
Table 2. Average mass loss rate for non-flaming experiments

Irradiance

kW/m2

Average Mass

Loss Rate

g/ s-m^

Percent of Peak Mass Loss

Rate Over Which Average Mass

Loss Rate Was Computed

Particle Board

PMMA

Rigid Foam

Carpet

Aircraft Panel

14.7 6.6

30.0 9.9

30.4 10.2

31.0 10.1

35.6 11.3

10.5 1.3

24.8 10.1

28.5 10.6

10.0 0.8

25.4 2.9

25.7 3.0

30.3 3.5

36.8 4.3

13.9 1.2

25.3 3.1

25.9 3.4

34.4 6.1

35.0 7.9

58.5 16.9

60.5 18.5

11.8 1.3

36.3 5.9

37.5 7.6

42.3 9.5

42.7 9.9

47.4 10.6

53.4 11.2

64.3 15.0

90

90

70

70

50

15
Table 3. Heat of gasification

Heat of Gasification

Material MJ/kg

Intercept

kW/m^

Particle Board 4.52 -15.0

PMMA 1.81 8.1

Rigid Foam 7.77 3.1

Carpet 2.50 15.8

Aircraft Panel 3.72 9.1

-16-
Table 4. Time to ignite

Time to Time to

Irradiance Ignition Irradiance Ignition

kW/m^ s kW/m^ s

Particle Board 11.6 611 Flexible Foam 24.8 12

13.0 440,475,510 25.1 17

19.9 180 25.2 12

20.9 165 49.8 2

24.7 118 49.8 2 24.9 120 50.2 3

25.2 115 74.8 1 25.4 105 75.0 1 49.7 23 75.2 1 50.0 31

50.1 25 Carpet 20.4 225

50.3 28 25.0 215

74.7 10 25.1 206

74.8 10 25.4 221

49.9 27

PMMA 20.0 194 50.2 27

24.7 173 74.6 13

24.8 113 74.8 13

25.1 113

25.3 111 Aircraft Panel 25.2 64

49.7 28 25.4 73

50.1 26 50.2 10

50.1 31 50.4 12

50.4 30 74.6 3 74.9 14 74.9 7 75.2 13

Rigid Foam 13.4 105

14.0 100

15.5 78

20.2 55

20.6 51

25.2 3

25.4 4

49.6 1 50.2 1 74.8 1 75.7 1

- 17 -
Table 5. Effective heat of combustion and stoichiometric ratio

Particle Board

PMMA

Rigid Foam

Flexible Foam

Carpet

Aircraft Panel

Irradiance

kW/m^

Effective Heat

of Combustion

MJ/kg

Stoichiometric

Ratio

r

Time for

Average

s

24.9 11.2 0.86 100-400

25.4 11.1 0.85 100-400

49.7 11.4 0.87 10-250

50.1 12.7 0.97 10-250

74.7 11.8 0.90 5-250

74.8 11.4 0.87 5-250

11.6 0.89

25.1 26.9 2.05 150-390

25.3 27.2 2.08 145-420

50.1 24.2 1.85 90-225

50.4 24.5 1.87 85-245

74.9 25.8 1.97 55-150

75.2 25.1 1.92 55-185

25.6 1.95

13.4 22.4 1.71 115-200

25.2 18.7 1.43 5-105

25.4 20.0 1.53 5-105

49.6 18.1 1.38 5- 75

50.2 18.3 1.40 0- 75

74.8 17.5 1.33 0- 65

75.7 18.0 1.37 10- 50

19.0 1.45

24.8 21.0 1.60 5- 60

25.1 20.1 1.54 10- 75

25.2 19.2 1.47 5- 50

49.8 15.8 1.20 5- 30

49.8 16.6 1.26 5- 30

50.2 21.6 1.65 5- 35

74.8 20.8 1.59 5- 35

75.0 17.6 1.35 0- 35

75.2 16.9 1.29 5- 25

18.8 1.44

25.0 15.8 1.20 180-515

25.4 16.8 1.28 185-505

49.9 17.0 1.30 5-160

50.2 17.1 1.31 5-160

74.6 17.7 1.35 5-155

74.8 16.2 1.24 5-155

16.8 1.28

25.2 11.5 0.88 60-330

25.4 12.0 0.91 65-330

50.2 11.3 0.86 5-200

50.4 14.9 1.14 5-200

74.6 17.2 1.31 5-150

74.9 16.0 1.22 5-150

13.8 1.05

- 18-
BUILDING

ROOF

(U

i-i 3

bO

19

ALL

DIMENSIONS

IN

METERS

- 21-

Figure

3.

Mass

loss

rate

for

particle

board,

non-flaming
T T O

O

CO

(gUj/s/6) 3iva sson ssviai

- 22-

Figure

4,

Hass

loss

rate

for

PMMA,

nonflaming
36.8

kW/m

T T T T O

in

in

CO

LJJ

I-

(^uj/s/6) 3iva sson ssvi^

- 23 -

Figure

5.

Mass

loss

rate

for

rigid

foam,

non-f

laming
59.5

kW/m

CO

LJJ 1

(gUJ/s/6) 3iVd sson SSVI^

- 24-

Figure

6.

Mass

loss

rate

for

carpet,

non-flaming
o

CO

LU

H

(gUj/s/6) 3iva sson ssviai

- 25 -

Figure

7.

Mass

loss

rate

for

aircraft

panel,

non-flaming
T T o

Cv

T^’ o

o

o

T“

o

O)

o

00

o

N.

o

cd

o

ir> o

o

CO

o

cvi q

o o« q o q o q q o

6 in d in d in d in

CO CO CM CM T“

(siaj/m>i) aoNviavaai

-26-

MASS

LOSS

RATE

(g/s/m2)

Figure

8,

Average

mass

loss

rate

for

particle

board,

non-flaming
(z'^/N\'>\) aoNviavaai

bOC

•HB

ta

>4-1

Ico

c>

a)

i-i 3

bO

- 27 -

MASS

LOSS

RATE

(g/s/m2)
0*09

E

(0

O)

LU

I-

<

GC

CO

CO

O

CO

CO

<

o

o

q q

CD 6

CO CVJ o o

o

(sUj/M>i) 30Nviavaai

- 28-

Figure

10.

Average

mass

loss

rate

for

rigid

foam,

non-flaming
(gUj/MM) aoNviavddi

bOC

1-1 e

tfl

Ic

oc

<

<u3

bO

i-( b

- 29 -

MASS

LOSS

RATE

(g/s/m2
75.0

LU

I-

<

QC

CO

CO

O

CO

CO

<

o O q o o

CD lO 6 lO

CO CO T—

(3UJ/M>0 30NViaVdai

c

•H%

c

oc

(Uc

«}a

4J

M-4«!o

p

CDp

o

Ip

(1) p

rtp

tn

COo

CO

CO

cOa

0) W)

rtp

9)

(Up

3

bO p

pt-l

- 30-
o

r— o

1

T \

w

1 1

1 1 1

"cS

CO 0•»—> a

a — <D CO E D

CO o 0

—

CO O

a

0

—

CO

0

E #

m _C0 z U-• •1

•-

•

—

• •/

• •

L 1 i 1 1 1 1 1 1 o O O o o o

o CO CVJ CD

CD CD CO

o

CO

o

CD

O

o

(N

O

LU

o

z

<

Q

<

QC

CO

(S)3I^I1

-31

Figure

13,

Time

to

Ignite

for

particle

board
500

o

o

00

o

CO

o

o

C\J

o

o

o

o o

o o

CO CVJ (s) 31^11

o o

o

-32-

IRRADIANCE

(kW/tn2)

Figure

14,

Time

to

ignite

for
O O O O O o

O 00 CD CM

CM

E

5

111 O

z

<

Q

<

cc

QC

(S) 3IAII1

- 33-

Figure

15.

Time

to

Ignite

for

rigid

foam
100

D•4-1 CC

k.CO

B

a 0 CO .i

k. 0 O 0 0 Q. O U) = 0 w

CD ^I Z Li. oo

CX)

CME

LUoz<Q<

cr

oc o

00 o

CO o o

CM

(s) 3mi - 34-

Figure

16.

Time

to

ignite

for

flexible

foam
o

o

o o o o

o o o o

lO CO CVJ (s) 3mi

o o

o

- 35 -

Figure

17.

Time

to

Ignite

for

carpet
100 o o o o o

00 CO

^

(S)3lrtll±

- 36-

IRRADIANCE(kW/m2)
50.0

kW/m

o

(jUj/M^i) 3iva asvanaa ivaH

- 37 -

Figure

19.

Heat

release

rate

for

particle

board
o

CO cvj CM •»- -1-

(gUJ/s/6) 3ivd sson SSVH

- 38-

Figure

20.

Mass

loss

rate

for

particle

board
74.7

kW/m2

(gui/M^i) 3±va asvanaa ivaa

T3

l-i to

U

3

bO

•r^

ClL.

- 39 -

TOTAL

HEAT

RELEASED

(MJ/m2)
1400

o

CM O 00 CO

^

c\j

LU

1H

31va 3SV313a 1V3H

-40-

Figure

22,

Heat

release

rate

for
75.1

kW/m

o

(/)

LU

(giii/s/B) 3iVd sson SSVl^

- 41-

Figure

23.

Mass

loss

rate

for
75.1

kW/m2

o

o

-42-

TOTAL

HEAT

RELEASED

(MJ/m
75.7

kW/m

CO

o

o

CO

(SUJ/M>1) 31Va 3SV313a iV3H

o

C\J

o

C\J

o

CM

O

00

if) o

^

in LU - 2

o

CM

o

O)

o

CD

o

CO

o

- 43-

Figure

25.

Heat

release

rate

for

rigid

foam
O CD CJ 00 O

Cvj 1- 1-

(3Uj/s/B)3iva sson ssvi^

- 44-

Figure

26.

Mass

loss

rate

for

rigid

foam
75.7

kW/m

-A5-

2.4

3.6

4.8

6.0

7.2

8.4

9.6

TOTAL

HEAT

RELEASED

(MJ/m2)
I oo ooo -46-

Figure

28.

Heat

release

rate

for

flexible

foam
o

O)

o

CO

CO CD

CO CVJ

CNJ

J o

(gUj/s/6) aiva sson ssviai

-47 -

Figure

29.

Mass

loss

rate

for

flexible

foam
75.0

kW/m

(giu/M>0 31Va 3SV313a 1V3H

TOTAL

HEAT

RELEASED

(MJ/m2
400 kA

74.7

kW/m2 - 49 -

Figure

31.

Heat

release

rate

for

carpet
74.7

kW/m2

(2U1/S/6) 3ivb sson ssvifti

-50-

Figure

32,

Mass

loss

rate

for

carpet
74.7

kW/m2

o o o o

o o o o

lO CO CJ

( 2

UJ/M>i) 3±vd asvanaa iv3h

-51-

TOTAL

HEAT

RELEASED

(MJ/m2)

Fi

:ure

33.

Total

r

i

1

^

ic

car

iet
160

Ml

n74.7

kW/m

T I

(gUi/M^I) 31va 3SV313a 1V3H

-52 -

Figure

34.

Heat

release

rate

for

aircraft

panel
T T a

o

iO

o

CsJ

o

in

_L

CO

(0

LU

1

(^uj/s/6) 3iva sson ssvi^

- 53 -

Figure

35.

Mass

loss

rate

for

aircraft

panel
74.7

kW/m

T r o

cvi

00

o

o

CM

31Vd 3SV313a 1V3H

- 54-

TOTAL

HEAT

RELEASED

(MJ/m2)

Figure

36.

Total

heat

released

for

aircraft

panel
'b>-lUA (f<Ev. 2 -ao) U.S. DEPT. OF COMM.

<?!EL!OGRAPHIC DATA

SHEET (See instructions)

1. PUBLICATION OR

REPORT NO.

2. Performing Organ. Report No. 3. PubI ication Date

NBSIR 84-2960 December 1984

*. '-ITLE AND SUBTITLE

I

! Heat Release and Mass Loss Rate Measurements for Selected Materials

5. AUTHOR(S)

W.D. Walton and W.H. Twilley

6. PERFORMING ORGANIZATION (If joint or other than NBS, see instructions)

national bureau of standards

DEPARTMENT OF COMMERCE

WASHINGTON, D.C. 20234

7. Contract/Grant No.

8. Type of Report & Period Covered

9. SPONSORING ORGANIZATION NAME AND COMPLETE ADDRESS (Street. City. State, ZIP)

U.S. Department of Transportation

Federal Aviation Administration

Technical Center

Atlantic City, N.J. 08405

10. SUPPLEMENTARY NOTES

Q2] Document describes a computer program; SF-185, FIPS Software Summary, is attached.

11. ABSTRACT (A 200-word or less factual summary of most significant information. If document includes a significant

bibliography or literature survey, mention it here) The purpose of this study was to measure fire parameters for a selected group of

materials. These parameters are to be used in a continuing study of flame spread.

The parameters measured are rate of heat release, rate of mass loss, heat of

gasification, effective heat of combustion, stoichiometric ratio and time to ignite.

Heat release rates and mass loss rates are given as a function of time for several

external heat flux levels. The rate of heat release is also given as a function of

the total heat released. The experimental results and analysis are shown for six

diverse materials representative of aircraft (interior panels, carpeting, and seat

cushions) and buildings (particle board, polymethyl methacrylate (PMMA) and rigid

foam)

12. KEY WORDS fS/x to twelve entries; alphabetical order; capitalize only proper names; and separate key words by semicolon s) aircraft compartments; aircraft fires; fire safety, fire tests, flame spread;

heat release rate; Interior finishes

13. AVAILABILITY

|_^ Uni imited

I I For Official Distribution. Do Not Release to NTIS rn Order From Superintendent of Documents, U.S. Government Printing Office, Washington, D.C.

20402.

Order From National Technical Information Service (NTIS), Springfield, VA. 22161

14. NO. OF

PRINTED PAGES

62

15. Pr.ce

$ 10.00