i , Submarine Compartment Fire

Study- Fire Performance

Evaluation of Hull Insulation

B. T. Lee and J. N. Breese

Center for Fire Research

National Engineering Laboratory

National Bureau of Standards

Washington, DC 20234

May 1979

Final Report

N

100

.U56

78-1584

Prepared for; Ship Damage Prevention and Control

Naval Sea Systems Command

Department of the Navy

Washington, DC 20362

NBSIR 78-1584

*•* SUBMARINE COMPARTMENT FIRE

STUDY-FIRE PERFORMANCE

EVALUATION OF HULL INSULATION

B. T. Lee and J. N. Breese

Center for Fire Research

National Engineering Laboratory

National Bureau of Standards

Washington, DC 20234

May 1979

Final Report

Prepared for; Ship Damage Prevention and Control

Naval Sea Systems Command

Department of the Navy

Washington, DC 20362

U S. DEPARTMENT OF COMMERCE, Juanita M. Kreps, Secretary

Jordan J. Baruch, Assistant Secretary for Science and Technotogy

NATIONAL BUREAU OF STANDARDS. Ernest Ambler, Director

TABLE OF CONTENTS

Page

LIST OF FIGURES iv

LIST OF TABLES V

U. S. CONVERSION UNITS vi

Abstract . . . 1

1. INTRODUCTION 1

2. FACILITIES AND EXPERIMENTAL TESTS 2 2.1 Full Size Compartment Fires 2 2.2 Quarter-Scale Compartment Fires 3 2.2.1 Modeling Principles 3 2.2.2 Model Experiments 4 2.3 Laboratory Tests of Fire Properties 5

3. RESULTS AND DISCUSSIONS 5 3.1 Assessment of Potential Fire Performance of Materials .... 5 3.1.1 Laboratory Fire Test Evaluation 5 3. 1.1.1 Ease of Ignition 5 3. 1.1. 2 Flame Spread 5

3.1.1. 3 Heat Release 6 3.1.2 Quarter-Scale Compartment Fire Testing 7 3. 1.2.1 Evaluation of Unprotected Hull Insulation ... 7 3. 1.2. 2 Evaluation of Some Fire Protective Coatings . . 8 3. 1.2.

Generation of Combustion Gases 9 3.1.3 Relationship between Laboratory Fire Tests and

Compartment Fire Tests 9 3.2 Comparison of Full- and Quarter-Scale Compartment Fires ... 10

3.2.1 Fire Buildup 10

3.2.2 Supporting Measurements 11

3. 2. 2.1 Thermal Fluxes 11

3. 2. 2.

Interior and Doorway Air Temperature

Distributions 11

3. 2. 2.

Air Velocity and Mass Balance across Doorway . . 12

3. 2. 2.Combustion Products 12

4. CONCLUSIONS 13

5. RECOMMENDATIONS 13

6. ACKNOWLEDGMENTS 14

7. REFERENCES 14

8. APPENDIX - LABORATORY FIRE TESTS 16

8.1 Ease of Ignition 16

8.2 ASTM E 84 Flame Spread 16

8.3 ASTM E 162 Flame Spread 17

8.4 Rate of Heat Release Calorimeter 17

8.5 Potential Heat Test 17

iii
f

LIST OF FIGURES

Page

Figure 1. Plan view of compartment arrangement showing locations

of ignition burner and instrumentation 19

Figure 2A. Quarter-scale compartment fire test prior to ignition ... 20

Figure 2B. Quarter-scale compartment fire test at flashover 20

Figure 3. Top of doorway air temperature histories for several

prototype fires and model tests using lintel III 21

Figure 4. Compartment air temperature profiles at time of peak

doorway air temperature 22

Figure 5. Doorway air temperature profiles at time of peak

doorway air temperature 22

Figure 6. Doorway velocity profiles for full-scale tests FS-1

and FS-2 23

Figure 7. Doorway velocity profiles for full-scale test FS-4 24

Figure 8 Carbon monoxide concentrations along doorway at time

of peak doorway air temperature 25

Figure 9. Oxygen depletion profile along doorway at time of peak

doorway air temperature 25

Figure 10. Proposed submarine fire test compartment with frame bays . . 26

IV
LIST OF TABLES

Page

Table 1. Materials used in the compartment and laboratory fire

tests 27

Table 2. Summary of full-scale tests and counterpart model tests . . 28

Table 3. Summary of model tests, scaled height above doorway

(lintel I) 29

Table 4. Model doorway dimensions 30

Table 5. Summary of model tests, 1.4 times scaled height above

doorway (lintel II) 31

Table 6. Model tests of fire barrier coatings 32

Table 7. Summary of model tests, 1.8 times scaled height above

doorway (lintel III) 33

Table 8A. Ease of ignition and flame spread properties of materials

used in compartment fire tests 34

Table 8B. Heat release rate and potential heat of materials used

in compartment fire tests 35

Table 9A. Ease of ignition and flame spread properties of other

submarine insulation materials 36

Table 9B. Heat release rate of other submarine insulation

materials 37

Table 10. Comparison of compartment air temperatures for fire

tests with three different doorway openings 37

Table 11. Concentrations of some combustion gases at top of

doorway 3 8 Table 12. Comparison of fire buildup in full-scale and

corresponding quarter-scale compartments 39

Table 13. Flux measurements at time of pea)c doorway temperature ... 39

Table 14. Calculated mass balance across doorway for three

compartment fires 40

Table 15. Comparison of measured model and prototype inflow air

velocities near bottom of doorway 40

Table 16. Carbon monoxide, carbon dioxide, and oxygen

concentrations and smoke measurements at doorway at

time of peak doorway temperature 41

Table 17. Relative concentrations of some combustion gases at top

of doorway for prototype and counterpart model tests ... 42

V
U. S. CONVERSION UNITS

In view of the present accepted engineering practice in this country,

we assist the readers interested in making use of the U. S. units by giving

conversion factors applicable to the metric SI system of units used in this

report.

Length

1 meter = 39.37 in

1 meter = 3.28 ft

Mass

1 kg = 2.20 lb

Temperature

Temperature in °C = 5/9 (temperature in °F 32)

Energy

1 kJ = 0.948 Btu

Power

1 kW = 0.948 Btu/s

VI
SUBMARINE COMPARTMENT FIRE STUDY-FIRE PERFORMANCE

EVALUATION OF HULL INSULATION

B. T. Lee and J. N. Breese

Abstract

Certain foam rubber materials which are currently

used to insulate the interior of submarines are shown to

possess a serious fire risk potential. Flame spread tests

often do not adequately reflect the fire hazard potential

of these materials. It is shown that compartment fire

testing is the only satisfactory method of evaluating these

kinds of materials at the present time.

Fire barrier coatings for protecting these hull

insulations are also investigated. Two candidate coatings

are found to prevent full fire involvement of an insulated

compartment following a moderately large flame exposure

and at the same time meet the Navy's elasticity requirement

for submarine application. The study includes comparisons

of model and prototype compartment fire behavior and demonstrates the practicality of using quarter-scale fire

tests for screening compartment finish materials.

Key words: Combustion products; fire barrier coatings;

fire growth; flame spread; foam insulation; heat release;

interior finish; laboratory fire tests; material ignitability

submarine compartment.

1. INTRODUCTION

Fire could represent a major threat to a submarine and to the life safety

of its crew. The spread of heat, smoke and potentially hazardous combustion

gases from a growing fire could overwhelm the normal cooling and filtering

systems. This danger is accentuated because of the confined space and the

limited, if any, means of securing refuge from the combustion products. It

is essential that any incipient fire be confined to its neighborhood of origin

or at least to a relatively small portion of the submarine for a sufficient

time to permit suppression of the fire.

Hull insulation materials provide a large area for exposure to an accidental fire aboard a submarine. To help contain the fire the interior

finish materials must not contribute significantly to the fire growth and

spread. Unfortunately, the fire performance of such materials is difficult

to assess solely on the basis of laboratory fire tests. In many instances,

the potential fire behavior of interior finish can be adequately appraised

only with compartment fire testing of the materials. However, such full-scale

testing is expensive, particularly when many materials are to be evaluated.

For the preliminary evaluation of materials, a suitable alternative to

full size compartment fire tests is the use of reduced-size model compartment

fire tests. Full-scale tests would be used only for confirmation of the important model test results, and the data from the full-scale tests could be used

to improve the model. This approach would thus reduce the amount of full-scale

testing needed in the future.

The work discussed in this report has the following objectives:

1
(1) To evaluate the potential fire hazards of the polyvinyl

chloride (PVC) nitrile rubber insulations, which are currently used for submarine insulation,

(2) To ascertain the effectiveness of candidate commercial

fire barrier materials for protecting such insulations

from fire, and

(3) To develop a suitable one-quarter size compartment fire

test for evaluating the fire performance of submarine

hull insulation.

This report describes the full-scale compartment fire tests of some protected and unprotected hull insulations and the quarter-scale modeling

of these fires. The work included quarter-scale compartment fire test com- parison of additional hull insulations and screening of candidate fire protective materials. Laboratory fire test results on the ignitability , surface

flammability and heat release are also given and compared with the performance

observed in the compartment fire tests. In this study the basic criterion

adopted for limiting fire growth required that the insulation and coating

materials, when subjected to a moderately large ignition exposure, must not

lead to flashover of the compartment. Flashover is defined here as the com- partment condition where the radiation level becomes high enough to spontaneously ignite light combustible materials such as newspaper in the lower half

of the compartment.

2. FACILITIES AND EXPERIMENTAL TESTS

2.1 Full Size Compartment Fires

Compartment fire tests of selected submarine hull insulation materials

were performed in a 3.0 x 3.0 x 2.3 m high compartment having doorway dimensions of 0.73 X 1.93 m high. Figure 1 is a plan view of the compartment

showing the location of instrumentation. All four bulkheads and the overhead

had 0.64 cm thick aluminum alloy plate or sheet mounted over 5.1 x 10.2 cm

steel spacer studs 40.6 cm apart. The deck consisted of 0.32 cm thick alumi- num sheets over a concrete floor. The room was located within a large building, so that the effects of temperature extremes and wind were eliminated.

Table 1 lists the insulations and decorative and fire protective coatings used

in the full- and quarter-scale compartment fire tests and in the laboratory

fire tests. The five full-scale compartment test arrangements are shown in

table 2. In each of these five setups the test material covered both bulkheads

and the overhead. A 30.5 x 30.5 cm porous ceramic plate diffusion flame burner, selected for ease of control and convenience in testing, served as the

ignition source. The burner surface was elevated 30.5 cm from the deck and

positioned in one back corner of the compartment. The burner used methane gas

and operated at a heat release rate of 62 kW for the first three tests with

the unprotected materials. The lining materials in the remaining two tests were protected with an intumescent paint, and a more severe burner heating

rate of 94 kW was employed to give a greater margin of safety in choosing fire

barrier coatings.

Location of all instrumentation in these compartment fire tests is

indicated in figure 1. The measurements which were made to characterize the

thermal environment in the compartment included vertical temperature profiles

down from the overhead and along the length of the doorway, vertical distribution of airflow velocities in the doorway, incident thermal radiation on the

floor and, in some tests, thermal flux to the overhead and/or to the bulkhead.

Auxiliary measurements to fully describe the fire included smoke obscuration,

oxygen depletion, carbon monoxide and carbon dioxide concentrations of the hot

gases exhausting from the upper part of the doorway. In full-scale tests

(FS-3, FS-4 and FS-5) the flow near the top of the doorway was also monitored
for the presence of hydrogen cyanide, HCN, and hydrogen chloride, HCl

Temperatures were measured with chromelalumel thermocouples made from 24 gauge

wire. Heat flux to the overhead and bulkhead surfaces and the thermal radiation incident on the lower part of the room were monitored with water cooled

total heat flux gauges of the Gardon type. Crumpled up newsprint on the deck

was also used to indicate if and when the irradiance was sufficient to ignite

such light combustible materials in the lower portion of the room. Bi-directional probes [1]1 were employed for measuring the air velocity and the occurrence of any flow reversal along the doorway. Smoke concentration in the

doorway exhaust was measured photometrically. Oxygen was sensed directly by

a chemical galvanic cell. Non-dispersive infrared analyzers were used to

record the concentrations of carbon monoxide and carbon dioxide. Indications

of the concentrations of HCN and HCl were obtained by drawing a sample of the

exhaust gases through commercial colorimetric detector tubes. Essentially, a colorimetric tube is a small-bore glass tube containing a chemical packing

which changes color when exposed to a specific component of a gas mixture, and

the length of the color stain is related to the concentrations of that

component.

2.2 Quarter-Scale Compartment Fires

2.2.1 Modeling Principles

The air temperature in the upper part of a compartment is a good measure

of its fire buildup [2] . When this air temperature reaches 500° C, there is

rapid pyrolysis and ignition of most combustible materials in the upper portion

of the space. When the air temperature near the ceiling reaches about 700° C,

ignition of light combustibles can occur in the lower part of the compartment

due solely to thermal radiation. A quarter-scale model having geometrically

scaled room dimensions has been effective in modeling the upper compartment air

temperature for the situation where the fire spreads up a combustible wall [2].

Temperature histories near the ceiling and at mid-height in the room were similar for both small-scale and full-sized room fires. The same approach has

been used with some success in the modeling of fires in a simulated Navy

berthing compartment [3]. In both of those modeling experiments the similarity

of temperatures between the model and the prototype was maintained by having

the same ratio of heat release rate to the volumetric rate of air inflow.

Since the portion of the room above the doorway traps the hot combustion products from the fire and is critical to the phenomena taking place in the room,

the doorway height, h, and consequently the lintel height were also scaled

geometrically.

The air inflow, which scales as wh3/2, was controlled by changing the width of

the doorway, w, in the model. These scaling rules are summarized as follows:

1. a) All compartment dimensions (width, length, height) are proportional to the scale factor.

b) The height of the doorway is proportional to the

scale factor.

c) The width of the doorway is proportional to the

square root of the scale factor, and

d) The thickness of the materials remains the same.

2. Rate of heat release of the ignition source, fuel con- tent and surface area of the lining material (insulation

on bulkheads and overhead) are proportional to a refer- ence area which was taken to be the floor area.

^Numbers in brackets refer to the literature references listed at the end of

this report.

3
3. Fire induced air supply rate is proportional to the same reference floor area. 2.2.2 Model Experiments

The model test enclosure was a one-quarter-scale replica of the full-scale

compartment except for the doorway opening. This enclosure, shown in figure 2,

consisted of a 0.64 cm thick aluminum alloy shell which was positioned over a 0.64 cm steel deck. The model enclosure having a doorway opening based on the

modeling principles discussed in the preceding section was used to provide a relative evaluation of the insulations and coatings in the tests shown in

table 3. The model with this doorway opening is hereafter referred to as the

lintel I model. At the same time the first three full-scale compartment fire

tests of foam rubber insulations and their counterpart lintel I model tests

shown on table 2 were performed. It was found that the peak fire buildup in

the lintel I model was considerably less than the fire growth found in two of

the full-scale room fire tests of these materials.

Fire tests in the model lined with fire-exposed fibrous glass insulation,

where the organic binder has burned away, indicated that the thermal radiation

levels on the deck and on the bulkhead surfaces away from the ignition flame were higher than those occurring in the full-scale tests because of the relatively taller flame in the model. Thus, the differences in thermal radiation

in the model and full-scale tests may not be the reason for the lower degree

of fire involvement in the model. A possible reason for this divergent behavior between the full- and quarter-scale tests could be due to the unequal con- vective heating of the interior in the two enclosures. With turbulent flow

over flat surfaces the convective heat transfer increases with the flow velocity. As the air velocities in the space vary roughly as the square root of the

scale factor [2] , the convective heating of the interior finish will be more

severe in the prototype than in the small scale model. This is particularly

important near and within the flame zone which extends upwards from the ignition source, where convective heating is the dominant mode of heat transfer to

the interior finish material.

No further attempt was made to study differences in convective heating

between the model and full-scale compartment fires nor to increase the con- vective heat transfer in the model. It was decided instead to compensate for

the lower degree of fire buildup in the model by increasing the radiative

environment by lowering the height of the doorway. To compensate for the

reduced doorway height so as to secure the proper air inflow to the fire, the

doorway must then be widened according to the flow parameter wh^/^^ Fire tests

in the model lined with fibrous glass insulation showed that although the peak

temperatures weren't too different, the average air temperature in the upper

half of the room and the thermal radiation levels in the room increased with

increasing depth of the doorway lintel. Two other lintel depths of 1.4 (onequarter) and 1.8 (one-quarter) of the full-scale lintel depth, corresponding

to the lintel II and III models, were then arbitrarily selected to study the

effect of doorway height. The dimensions for these three openings are shown

in table 4. The lintel II model was used for the test series indicated in

table 5 and for the screening of most of the candidate fire barrier materials

outlined in table 6. In the modeling of the five full-scale tests with the

lintel II model, the model predicted a much lower degree of fire buildup than

that occurring in one of the full-scale tests. In an effort to achieve a closer simulation of prototype fire behavior the lintel III model was explored

for the test arrangements shown in table 7.

Instrumentation in the model was similar to that used in the full size

compartment, except that carbon dioxide was not monitored and carbon monoxide

and oxygen were measured only at the top of the doorway. Furthermore, only the

air velocity near the bottom of the doorway was recorded during each model fire

test. In all of the model tests, except for test 1, a gas burner positioned

in one back corner, whose heat release rate was scaled to the two prototype

4
rates of heat release, served as the ignition source. Test 1 was performed as

a preliminary experiment to show if an oxygen-acetylene torch was suitable as

an ignition source. The torch was located against the lower back corner of the

compartment. The torch flame exposure was found to be too small to adequately

appraise the potential fire risk of the hull insulations and was replaced by

the more realistic and moderately severe exposure from the gas burner.

2.3 Laboratory Tests of Fire Properties

The hull insulation materials and coatings were also evaluated by

laboratory fire tests for ease of ignition, surface flammability and heat

release characteristics. The time at which materials contribute to a fire upon

contact with flames from incidental or low energy fires was determined with the ease of ignition test [4] described in section 8.1 of the appendix. Two ASTM

tests, the E 84 tunnel [5] and the E 162 radiant panel [6] tests, were employed

for measuring the flame spread along materials. These tests are described in

sections 8.2 and 8.3. The rate of heat release and potential heat of these

materials were measured with the rate of heat release calorimeter [7] and the

potential heat test [8], discussed in sections 8.4 and 8.5, respectively.

3. RESULTS AND DISCUSSIONS

3.1

Assessment of Potential Fire Performance of Materials

3.1.1

Laboratory Fire Test Evaluation

For the materials used in the compartment fire tests, the ignition, flame

spread and heat release properties, as measured with the tests discussed under

section 2.3, are shown in tables 8A and 8B. In addition, for comparative purposes, other submarine interior finish materials were subjected to some of

these laboratory tests. This data is given in tables 9A and 9B. For most

applications aboard a submarine, 2.5 cm nominal thickness insulation is used.

This thickness material was employed in the ease of ignition, heat release rate

calorimeter and potential heat tests. However, the flammability requirements

in the Navy's material specifications call for ASTM E 84 testing of 1.3 cm thick specimens of the materials. Therefore specimens of both thicknesses for

each of the materials used in the compartment fire tests were evaluated with

the E 84 and E 162 tests.

3.

1.1.1

Ease of Ignition

An earlier study [9] has suggested that materials requiring flame exposure

times of less than or equal to 60 seconds for the onset of fuel contribution,

using the ease of ignition test, could contribute to an early compartment

flashover. The ease of ignition test results in table 8A show that the fibrous

glass insulations and the B2 and C2 materials having a protective coating of

0-987 or 0-9788 over primer coats of A207 had flame exposure times of greater

than or equal to 60 seconds for the onset of fuel contribution. The only other

material in tables 8A and 9A which performed well on this test was the B2 foam

with the 0-9788 coating over the 0-634 paint. However the B2 foam with a sur- face coating of 0-987 alone or over a primer layer of the 0-634 required less

than 30 seconds of flame exposure before contributing fuel to the flame. In

every case where the insulation surface had only a decorative paint such as A207, D2707 or 0-634, the specimen experienced a longer time for fuel

contribution than that for the unpainted material.

3. 1.1.

Flame Spread

Flame spread along a material is presently measured by the ASTM E 84

tunnel and the ASTM E 162 radiant panel. Flame propagation in the former test

is in the direction of the ventilation through the tunnel. The heat and fuel

generated from the burning material also flows in the same direction and

5
contributes to the extension of the flame. Flame travel on the E 162 radiant

panel is downward, counter to the air updraft. Heat produced by the burning

specimen moves vertically away from the specimen and does not contribute to

the flame spread except for the heat that is generated locally in the vicinity

of the leading edge of the flame. Both modes of fire spread occur in compartment fires. In the initial stages of a fire, the flame spread along the

interior finish is upwards from the ignition flame and resembles the flame

propagation along the E 84 tunnel. Downward flame propagation as well as lateral flame travel across the bulkhead and overhead, away from this initial

flame zone, may be more suitably evaluated with the E 162 test. A flame spread

factor and the heat contribution are independently measured in the latter test

and combined to give an overall flame spread index for the material.

Navy fire performance requirements for bulkhead and overhead finish

materials, as stated in MIL STD 1623 B [10] , presently call for a maximum flame

spread limit of 25 on the E 84 test. This requirement has helped to screen out

some serious fire risk materials. Some Navy compartment fire tests [3] have

demonstrated that a flame spread limit of 25 or less on the E 162 test has also

helped in the selection of fire safe materials. Data from the ASTM E 84 tests,

given in tables 8A and 9A, show the average as well as the range of flame

spread classification (ESC) values for three tests of each submarine insulation, unless noted otherwise. Variation between tests of the same material

can be large, e.g., ESC values varying from 72 to 177 and from 36 to 79 for the

2.6 cm A6 and 2.7 cm C2, respectively. Only the 1.3 cm thick B2 material had

an average rating of 25 with the next best insulations, the 1.3 cm thick A2

and C5, barely exceeding the acceptance limit.

Flame spread results from the E 162 test, indicated on the same tables,

show a much wider range of variation for this type of material. The flame

spread index. Is/ for several tests of the same material could have large

variations, e.g., index values between 4 and 107 and between 62 and 1359 for

the 2.7 cm B2 and 2.4 cm C4 insulations, respectively. The large variation in

the test results of these nitrile foam materials could have also obscured the

effect of surface coatings and paints. For instance, when fairly inert fibrous

glass having a glass cloth surface was painted with the A207, D2707 or 0-634

coatings, higher values of Fg and Ig resulted. Yet C2 specimens painted with

two of these decorative coatings showed lower Fg and Ig ratings than those for

the unpainted samples (table 9A) . The wide variations in the E 162 evaluations

of these foam materials, due to the unsteady nature of burning of such materials, make it difficult to ascertain which of these materials actually comply

with the Is limit of 25.

3. 1.1. 3 Heat Release

There is a necessity for limiting the rate of heat production from

materials to help avoid a rapid fire buildup in the compartment. There is also

the need to limit the total potential heat of the materials in a compartment

in order to restrict the duration of the fire. The latter requirement is

intended to limit the effect of the fire on the structural integrity of the

compartment components as well as to reduce the probability of fire penetration

into adjoining occupancies.

Rate of heat release data taken at a moderately severe fire exposure of

4 W/cm^ along with the potential heat values for some submarine interior finish

are indicated in tables 8B and 9B. Most of the foam insulations had a maximum

one minute average heat release rate in the vicinity of 7 to 9 W for each cm^

of the exposed surface area. The B2 painted with the 0-987 had the lowest rate

at 5.8 W/cm^ while the C4 material experienced the highest value at 12.1 W/cm^

For comparative purposes, the one minute average rate, at a fire exposure of

4 W/cm^, for wood is about 10 W/cm^ [7], and the rates for the decorative laminates, used on some bulkheads, such as 0.20 mm vinyl and 0.89 mm melamine are about 3.3 and 5.5 W/cm^ respectively [9]. Laboratory heat release rate data

is often difficult to relate to a compartment fire involving the interior

6
finish. A material's rate of heat generation can be a strong function of the

radiant exposure history. The interior surfaces in a room would generally be

exposed to a non-uniform fire exposure throughout the space, and portions of

the room surface could be in various stages of fire involvement. In addition,

the rate of heat production in the room is a function of the fire affected

area, which in turn depends on the rate of surface flame spread. To avoid a serious fire risk situation some limitation should be put on the heat generation rate, as measured with the laboratory rate of heat release calorimeter,

in conjunction with restrictions on the time to fuel contribution from the

ignition test and the flame spread rating of the material.

Potential heat test results for several representative submarine

insulations are given in tables 8B and 9B. On a weight basis, the potential

heat of these materials is about the same as wood. Expressed in terms of the

exposed surface area, these low density materials have values of 43 to 76 MJ/m^

as compared with, e.g., 7 and 24 MJ/m^ for the 0.20 mm vinyl and 0.89 mm melamine laminates, respectively. A commonly used relation between fire severity

and fire load [11] shows that for every 12 kg of wood equivalent load per m^

of deck area increase in fire load, or 240 MJ per m^ of deck area, the fire

severity, in terms of ASTM E 119 type of fire exposure, increases by 1/4 hour.

3.1.2 Quarter-Scale Compartment Fire Testing

A summary of the tests with the model enclosure is presented in tables 3,

5, 6 and 7. The first test of the series demonstrated that an oxygen acetylene

torch, positioned in one back corner of the model, would only char or burn away

the foam insulation around the flame impingement zone; also, compartment temperatures did not exceed 100° C over a ten-minute test period. Subsequent

tests used a gas burner having an output of either 3.9 or 5.9 kW, corresponding

to 62 and 94 kW in the counterpart full size tests, respectively, as the ignition source. The thermal contribution of the ignition source represents only

a small part of the heat generation rate known to result in flashover conditions in the compartment. Flashover experiments in full and quarter size rooms with an opened doorway have demonstrated that roughly 650 kW and 340 kW were necessary to have flashover in a well insulated 3.0 x 3.0 x 2.3 m high space

at times of 0.75 and 5.0 minutes, respectively [12]. Therefore, the low and

high ignition sources would supply only about 10 and 15%, respectively, of the

rate of heat release needed to attain flashover in a short duration fire and

approximately 18 and 28%, respectively, for flashover in the vicinity of five

minutes. Consequently, flashover will not occur if the compartment space

interior walls and/or additional combustible contents do not supply the

additional energy release.

Compartment and doorway air temperatures are given for each model test.

Compartment air temperatures were occasionally affected by the localized heating of the thermocouple, while the doorway air temperature was more representative of the average overhead compartment air temperatures.

3. 1.2.1 Evaluation of Unprotected Hull Insulation

Fire tests of the unprotected materials with the model having the lintel I doorway are given on table 3. A comparison of the doorway air temperatures in

the table disclosed that the model fires with the unpainted insulations C2 and

B2 behaved much like the fire test with the fairly inert fibrous glass when

the low ignition setting was used. At the high ignition exposure the model

fire with the C2 again performed similarly to the test having the fibrous

glass, but model experiments with the unpainted B2 and A2 , tests 19 and 20,

led to flashover of the space after 1.2 and 1.4 minutes following ignition.

Test 3 indicated that a decorative paint over an inert surface did not increase

the fire buildup. However, decorative paints over the nitrile foams C2 and B2

increased the surface flaming to the extent where flashover occurred in seven

of the eight cases where these foams were painted. In another model fire where

the insulation was J2 foam painted with A207 flashover also occurred.

7
Fire tests with the quarter-scale compartment having the lintel II doorway- are outlined in table 5. Model fire test 22 was similar to tests 4 and 5 in

table 3 except for a 7% lowering and 11% widening of the doorway. While only

doorway air temperatures of about 215° C were found in tests 4 and 5, air temperatures of almost 600° C were measured in the doorway of test 22. Even when

the heat release rate of the ignition source in tests 4 and 5 was increased by

40%, as in tests 16 and 17 in table 3, doorway temperatures increased to only

240° C. For the C2 insulation the lowering of the doorway by 7% had a much

greater effect on the fire than a significant increase in the size of the fire

initiation source. As part of the test series with the model having the lintel II doorway,

acoustical fibrous glass, chloroprene-laminated nitrile foam, spackled cork

and chlorinated alkyd paint over fibrous glass were evaluated under the high

ignition setting. The model having the acoustical glass experienced doorway

temperatures of less than 80° C above that found for the fire with the

unpainted fibrous glass. Chlorinated alkyd paint had little effect on the test

results. The test with the spackled cork lasted 3.4 minutes before flashover

occurred. The chloroprene-nitrile foam performed well for seven minutes, at

which time the fire accelerated to flashover by eight minutes. This chloroprene, however, is not suitable for submarine finish because of its open cell

structure, which could absorb fuel in the event of a nearby oil leak and then

act as a wick if ignited.

Model fire tests in the compartment with the lintel III doorway are given

in table 7. Tests 33 and 34 were similar to the tests 4 or 5 and test 10 in

table 3, respectively, except for the doorway dimensions. In tests 33 and 34,

the doorway was lowered by 14%, and both tests experienced flashover.

A brief summary of the modeling experiments with the quarter-scale

compartments having the three doorway lintel heights for the unpainted B2 and

C2 nitrile foam materials is given in table 10. The data show that for tests

of these materials, small decreases in doorway height led to relatively large

increases in compartment interior and doorway air temperatures. Lowering the

doorway can sometimes have a greater effect on the fire buildup than a fairly

large increase in the size of the fire initiation source.

3. 1.2. 2 Evaluation of Some Fire Protective Coatings

Candidate fire barrier materials used in this study are shown in table 6.

The coatings that helped prevent flashover of the compartments with either the

lintel II or the lintel III doorway and an interior finish of C2 or B2 foam,

under the high ignition source setting, were the following:

1. 0-987 with and without primer coats of A207

2. 0-9788 with an undercoating of 0-634

3. 0-330 latex with an undercoating of 0-634

4. Z-3300

In tests 38, 45, 46 and 47, 0-987 was applied over primer coats of A207

to simulate the application on existing submarines where decorative paints had

been used. 0-987 over bare C2 and B2 insulations, tests 37 and 44, and over primer coats of A207, offered at least ten minutes of protection against com- partment flashover. However, when the protective layer is too thin, e.g., about 0.018 cm thick as in test 34, the degree of fire protection is compro—

n'ised. Even when only the compartment lining along the upper half of the bulk—

head and the overhead is covered with a 0.025 cm thick coating of 0—987, as in

test 47, a full ten minutes protection still resulted.

8
The 0-9788 coating is identical to the 987 formulation except for the

addition of a fungicide. Occasionally there is a problem with poor surface

adhesion with both of these coatings unless a suitable primer paint is used.

In test 50, the B2 foam was coated with just the 0-9788. Within a few seconds

following introduction of the ignition flame, the fire barrier paint on the

overhead began to flake off, resulting in a flashover at about four minutes.

Test 51 was protected with the 0-987 and survived the test duration of ten

minutes without reaching flashover. The application of a primer coat of 0-634

before coating with the 9788 paint, as in test 48, helped alleviate the problem

of the latter paint separating from the overhead. The compatibility of chlorinated alkyd over the 0-9788 coating with the 0-634 primer was evaluated in test

49. At 15 seconds into the test, large sections of the alkyd paint started to

peel and fall from the overhead.

The remaining two candidate coatings, which were effective in preventing

flashover over the ten minute test duration, had other drawbacks. The 0-330

latex cracked easily and chipped off when it was handled. The Z-3300 was too

rigid to tolerate much vibration and separated readily from the foam when the

latter insulation was slightly flexed several times.

3. 1.2. 3 Generation of Combustion Gases

Since some of these insulation materials are organic chlorine- and

nitrogen-containing compounds, the principal toxic combustion products are presumed to be CO, HCN and HCl. Other combustion products may be formed and

toxicological screening tests using animals may be necessary to avoid the

introduction of super-toxicants. Concentrations of HCN, HCl and CO in the hot

combustion gases exhausting from near the top of the doorway were measured in some of the quarter-scale fire tests of insulations with and without fire protective coatings. This data is presented in table 11. In test 31 with the

painted spackled cork, flashover occurred, and concentrations of CO and HCN were measured at 2.0% and 100 ppm at five minutes, respectively. Where flash- over occurred and the interior finish was a nitrile foam, tests 23, 33, 34, and

50 in table 11, relatively high concentrations of both HCN and CO were found

for both bare and painted foams. In these four tests the CO levels averaged

3.0% and the HCN concentrations reached 600 ppm or higher. Where there were

lower CO concentrations, HCN levels were also lower, but not proportionately

so. In the five cases in table 11 where 40 ppm HCN were measured, the concen- trations of CO averaged 0.6%. For the eleven cases involving the foam insulations and where 5 ppm or less of HCN were found, the levels of CO averaged

0 . 2 %.

Concentrations of HCN and HCl were estimated with colorimetric indicator

tubes. This detection technique gives only an approximation and is affected

by elevated temperatures and moisture in the sampling line. HCl analysis with

the tubes has the added disadvantage in that indication of the gas can be upset

by the presence of the oxides of nitrogen. When the concentrations of NO and

NO2 are higher than that for HCl, there may be no indication of the HCl using

this method. In all of the model tests shown in table 11, only test 34 with

the unpainted B2 foam resulted in measurable HCl concentrations above 200 ppm.

It is apparent from the data given in table 11 that if flashover can be

prevented, the generation of the combustion gases HCN, HCl and CO will be

minimized. The paints in table 11, by themselves, did not appear to contribute

significantly to the production of these gases. On the contrary, the fire

resistive coatings reduced the generation of combustion products by preventing

full fire involvement of the space.

3.1.3 Relationship between Laboratory Fire Tests and

Compartment Fire Tests

No single small-scale laboratory test can fully determine the fire hazard

of materials. Each of these tests can only indicate one or more components of

9
the fire risk potential of materials. The discussion in section 3. 1.1.1

concerning the results from the ease of ignition tests suggested that the

unprotected foams may pose a serious fire risk potential. The ignition data

also suggested that the B2 insulation having a protective coating of 0-987 over primer coats of A207 was acceptable. These findings were consistent with the

full-scale compartment fire test results shown in table 2 for the same materials. However, B2 coated with the 0-987 without the primer failed the ignition

requirement and yet performed well in the full-scale compartment fire test.

As for flame spread ratings discussed in section 3. 1.1. 2, the unpainted

B2 insulation satisfies the present Navy ASTM E 84 requirements for a fire

safe material. Yet the compartment fire test of this same foam insulation,

test FS-3 in table 2, indicated that it was a potentially serious fire risk

material. The A2 foam barely exceeded the "safe" flame spread limit of 25 on

the ASTM E 84 test; yet model test 20 in table 3, which was lined with this

insulation, experienced flashover in a little over a minute. Data from the

ASTM E 162 tests, shown on tables 8A and 9A, indicated that the unpainted C2,

C7 and C8 foam insulations had averaged ratings of about 25, implying low fire

risk materials. These ratings for materials are difficult to relate to the

materials' behavior in compartment-type fires. The large variation existing

between the ASTM E 162 tests of the same material introduces even more uncer- tainty to the interpretation of these ratings. The C7 and C8 materials were

not tested in a compartment, but the full-scale test FS-2 of the C2 foam demonstrated that it was a potentially fire hazardous insulation. These findings

demonstrated that flame spread ratings by themselves are not capable of

screening out potentially high fire risk interior finish. This conclusion is

confirmed by room fire studies conducted at Underwriters Laboratories [13]

where little correlation was found between the flame spread ratings for some interior finish and the degree of fire buildup in a 2.4 x 3.7 x 2.4 m high

room. Their test compartment was lined with plastic board materials and a burning 20-pound wood crib, positioned in one corner, served as the ignition

source. These tests demonstrated that fires with some plastic interior finish

having a 25 or lower rating on either or both of the E 84 and E 162 tests still

led to flashover of the compartment.

The potential heat and rate of heat release data for materials are also

difficult to relate to compartment fire tests of the materials. Usually materials which have a high rate of heat release will contribute more to the fire

buildup. Materials with a high potential heat will result in a longer duration

fire. Presently these two fire properties can be used to eliminate only those

materials having significantly higher potential heat and rate of heat release

values than the rest of the candidate materials. For the submarine foam insulations the potential heats only varied between 4 to 6 kJ/cm^, and no single

material stood out as being much worse than the rest. A review of the rate of

heat release data in tables 8B and 9B shov/ed that these foam insulations had

maximum one-minute rates which varied from 6.6 to 12.1 W/cm^ with no one material being significantly worse than the others.

3.2 Comparison of Full- and Quarter-Scale Compartment Fires

3.2.1 Fire Buildup

Doorway and interior air temperatures and flashover times for the five

f'^li“Scale tests and their corresponding model tests are presented in table 2.

Whenever a newsprint flashover indicator on the deck ignited during a test,

flashover was assumed to have occurred. Ignition of the newsprint or some designated minimum doorway or interior air temperatures are only rough indicators of flashover because of the variation in the thermal and physical properties of crumpled newsprint, the non-uniform distribution of temperatures

throughout the compartment, and the differences between tests of the combined

thermal radiation from the smoke, the hot air and the heated surfaces. The hot

air inside the compartment usually became well mixed by the time it exhausted

through the doorway. Consequently, doorway temperatures may be more reliable

10
flashover indicators than the interior air temperatures. In every case where

an ignition of the newsprint indicator had occurred, room and doorway temperatures either had attained or continued to increase to at least 650° C and

550° C, respectively. In comparing model and prototype results only broad

categories of fire involvement should be considered. For example, the fire

buildup could be described as low, moderate, or extensive, corresponding to

doorway temperatures of less than 250° C, between 250° C and 450° C, and above

450° C.

The model fires in tests 4 and 10, employing the lintel I doorway, failed

to achieve the same degree of fire buildup as that found for their counterpart

full-scale tests, FS-2 and FS-3. Whereby the latter two fires attained flashover, the model fires reached doorway air temperatures of only about 200° C.

The peak fire development in the model fires with the lintel II doorway, tests

22, 23, 44 and 46, simulated the fire buildup in their counterpart full size

tests reasonably well. However, test 24, with this lintel II doorway, did not

result in flashover, which occurred in its corresponding full-scale test FS-3.

The fire buildup in the quarter-scale tests, 33, 34 and 51, having the

lintel III doorway, was in reasonable agreement with the degree of fire

involvement observed in their corresponding prototype fires. Figure 3 shows

the doorway air temperature variation with time for the model tests having the

lintel III doorway and for their counterpart full size fires. The model fires

developed slower, but the peak fire buildup, as evidenced by the occurrence of

flashover or by the maximum air temperature, simulated the full-scale behavior.

A condensed version of table 2, showing a comparison of the fire buildup

in the full- and quarter-scale compartment fires, is given in table 12.

3.2.2 Supporting Measurements

3. 2. 2.1 Thermal Fluxes

Flux measurements at the time of peak doorway temperature for the

full-scale and corresponding quarter-scale tests are indicated in table 13.

The average irradiance on the deck at which flashover occurred was 2.2 W/cm^

for the full-scale fires FS-1, FS-2, and FS-3, and 2.4 W/cm^ for the model

fires 23, 33 and 34. Irradiance levels on the deck for tests FS-4 and FS-5 were also lower than those in their counterpart model tests. This was also

observed in tests where the interior finish was an inert fibrous glass insulation [12] . The higher flux probably resulted from the relatively taller burner

flames in the model and from the relatively larger heated surface area in the

model which occurred as a consequence of the lowered lintel.

3. 2. 2. 2 Interior and Doorway Air Temperature Distributions

The vertical air temperature profiles inside the compartment and along the

doorway for three prototype fires, at their respective times of peak air temperature as measured at a location 10.2 cm below the doorway lintel, are shown

in figures 4 and 5. Superimposed on the figures are the corresponding test

data from the model tests 33, 34 and 51 with the lintel III doorway. The times

to reach the peak doorway air temperature for tests FS-2, 33 and 34 also cor- responded to the times for flashover, whereas flashover occurred seconds after

the peak doorway air temperature was attained in test FS-3. In the model tests

33 and 34, temperatures were lower than in the prototype; and consequently, the

model fires required a longer fire exposure of the insulation in order to reach

flashover. For model test 51 and its corresponding prototype fire FS-4, the

fire was confined principally to the zone in contact with the flames from the

ignition source, producing only a moderate air temperature rise. The vertical

distribution of temperatures below the center of the overhead indicated much

higher temperatures in the model than those in the prototype fire. However,

these temperature differences in the upper part of the compartment did not show

up in the doorway temperature profiles. This may be explained by the relatively taller flame heights in the model. The higher flames could have

11
resulted in a more intense localized heating of the strand of thermocouples in

the upper region of the compartment. However, the heated air in the compartment space became well stirred by the time it reached the doorway. This is

evident from the similarity in the doorway temperature profiles for the two

tests

3. 2. 2. 3 Air Velocity and Mass Balance across Doorway

Full-scale velocity data along the doorway centerline were available only

for FS-1, FS-2 and FS-4, and these are shown in figures 6 and 7. For a quick

fire development leading to flashover, such as those occurring in tests FS-1

and FS-2 and their counterpart model fires, doorway velocities change rapidly.

Initially there is a rapid expansion of the compartment air, similar to a low

order explosion, which results from the sudden surge in the temperatures in the

space. Air inflow is, at first, very low but there is a high rate of hot air

exhausting from the compartment. Mass balances based on velocity measurements

across the doorway for these compartment fires are presented in table 14. For

FS-1 and FS-2 and during the first 15 to 20 seconds of test FS-4 the flow out

of the compartment greatly exceeded the airflow entering the space. From the

temperature variation with time inside the compartment for tests FS-1 and FS-2,

the excess of the mass flow out over that flow into the space was estimated to

be approximately 20 kg/min over the time interval from 0.13 to 0.50 minutes.

This compares with the value of about 40 kg/min calculated from the velocity

measurement in the doorway. Non-uniform distribution of the flow across the

width of the doorway, together with thermal radiation errors in temperature

measurement, could have accounted for this discrepancy in estimating the mass

flow leaving the compartment. In test FS-4, where only a slow and moderate

fire buildup occurred, there was a rough balance of the flow entering and

leaving the compartment at times longer than 20 seconds.

A comparison of model and prototype velocities is almost impossible during

the highly transient fire phenomena taking place in tests FS-1 and FS-2.

However, the data from FS-4 can be compared with the velocities from the

quarter-scale tests 44 and 51. Scaling principles indicate that velocity

should vary with the square root of the scale factor [2]

,

meaning that the

prototype velocities should be twice as large as the model velocities. This

scaling of velocity has been experimentally verified for fires performed in the

one-quarter-scale compartment lined with fibrous glass [12] . Table 15 shows

that the velocity ratio of the full-scale data to the model values is roughly

about two.

3. 2. 2.

Combustion Products

Measurements of carbon monoxide, carbon dioxide, oxygen depletion,

hydrogen cyanide, hydrogen chloride along with the smoke production data for

the prototype and counterpart model compartment fires are indicated in

tables 16 and 17. The CO and O 2 data shown in table 16 indicate that the CO

concentrations measured near or at flashover were higher and the O 2 levels were

lower in the prototype tests than those for the model fires. This was a direct

consequence of the more intense fire development in the full-scale fires at the

time of flashover. Even though the temperatures for FS-2, FS-3 and their cor- responding model fires, shown in figures 4 and 5, clearly showed a more intense

fire buildup in the prototype fires near or at flashover, model tests can still

be used to roughly predict full-scale behavior. For example, the quarter-scale

tests gave high CO and low O 2 levels when their counterpart prototype tests did

so. The concentrations of CO and the oxygen depletion, measured along the upper

half of the doorway and given in table 16, are also presented in figures 8 and

9.

An interesting observation is that the carbon monoxide and oxygen

depletion profiles in the full-scale tests which experienced flashover did not

look like their temperature profiles in the upper half of the doorways as shown

12
in figure 5. As for the generation of HCN and HCl, the data in table 17 show

that the concentrations of these gases roughly followed the generation of CO

in both of the model and full size fires.

Smoke measurements from both model and prototype fires, presented in

table 16, indicate that smoke concentrations were a magnitude higher for the

tests where flashover occurred than the smoke levels in the tests where only

a moderate fire buildup was found. Smoke levels in the quarter-scale tests,

expressed as an optical density per meter of smoke path length, were about

twice as high as those in the full size fires.

4.

CONCLUSIONS

1. The PVC nitrile rubber foams tested provide a potentially serious fire

hazard when used unprotected as hull insulation in submarines. This is

particularly true because of the rapidity of the fire buildup once these

materials become involved. Flashover occurred in less than one minute in

the full-scale compartment tests of these materials.

2. Two intumescent paints (0-987 and 0-9788) were identified, which if

applied in sufficient thickness (at least 0.025 cm), would provide at

least ten minutes delay time before the onset of flashover. These paints

met the elasticity requirements for the above application. These coatings

greatly reduced the overall generation of carbon monoxide, hydrogen

cyanide, hydrogen chloride, and smoke in the compartment fires by preventing much of the foam surface from being involved in the fire.

3. The present criterion based just on the flame spread ratings from the

ASTM E 84 tunnel test does not adequately reflect the fire hazard of these

materials. Ignition, flame spread, heat release and smoke generation

characteristics of the material are all important in determining its

potential fire hazard.

4. At the present time there is no demonstrated method of eliminating the

full-scale compartment fire test for determining the suitability of an interior finish material for shipboard and submarine application.

5. The quarter-scale model test is useful as an economical screening tool

for evaluating a large number of materials. It offers advantages similar

to the full-scale test in that for any given fire initiation source, the

ignition, flame spread, heat release and smoke generation characteristics

of the interior finish, along with the complex effects of the thermal

reinforcement on these properties as the fire grows, are all automatically

included. The final approval of materials should, however, at this stage,

be based on the results of a full-scale test.

6. A modification of the scaling rules with regard to the height of the room above the top of the doorway was preliminarily examined during this

project. It was found that better agreement could be obtained between

the full-scale and the quarter-scale tests if the doorway height was reduced by 14% in the model.

5.

RECOMMENDATIONS

1. There is a need to evaluate the fire behavior of these insulations under

a more realistic compartment configuration such as the proposed test room

shown on figure 10. The interior of a submarine has frame bays or ribs

every 0.6 to 0.9 m apart. Each rib is perpendicular to and protrudes 20

to 25 cm from the steel hull and extends around the inside perimeter of

the submarine. The effect of these frame bays on the fire is uncertain.

They could act as fire stops, inhibiting the lateral spread of the fire,

13
or they could channel the fire to the overhead, and intensify the local

fire involvement to the point where subsequent fire spread accelerates.

Currently, the Navy has an ongoing program at the National Bureau of

Standards to study the effect of these frame bays on compartment fire

buildup.

2. Further effort by the Navy to adopt the present quarter size room fire

test for general shipboard interior finish is recommended. Although the

model test in its present state can be used to screen submarine hull insulation materials, more research on the type and size of the fire initiation source is necessary before the test can be adopted for the more

general needs of the Navy. The ignition source used to evaluate materials

must be consistent with their intended use. For example, the desired fire

initiation exposure for assessing the potential fire risk of shipboard

interior finish may be quite different from that for screening the com- ponents of building construction. Furthermore, the testing of overhead

finish used on surface ships, for example, might require an ignition

source having a higher rate of heat generation than that needed for

evaluating bulkhead sheathing to adequately screen such materials.

6 . ACKNOWLEDGMENTS

Appreciation is expressed to Mr. Charles Veirtz, who built the test

compartments and performed the actual testing, and to Mr. W. J. Parker for his

helpful comments throughout the project.

This study was supported by the Naval Sea Systems Command, Department of

the Navy, under the direction of Mr. Dallas Whitehurst.

7. REFERENCES

[1] McCaffrey, B. J. and Heskestad, G. , A robust bi-directional low-velocity

probe for flame and fire application. Combustion and Flame, Vol. 26,

125-127 (1976)

[2] Parker, W. J. and Lee, B. T. , A small-scale enclosure for characterizing

the fire buildup potential of a room, Nat. Bur. Stand. (U.S.), NBSIR

75-710 (June 1975)

[3] Lee, B. T. and Parker, W. J., Naval shipboard fire risk criteria-berthing

compartment fire study and fire performance guidelines, Nat. Bur. Stand.

(U.S.), NBSIR 76-1052 (July 1976).

[4] Lawson, J. R. and Parker, W. J. , Development of an ease of ignition test

using flame impingement, Nat. Bur. Stand. (U.S.), NBSIR, to be published.

[5] Standard Method of Test for Surface Burning Characteristics of Building

Materials, ASTM E 84-70, American Society for Testing and Materials.

[6] Robertson, A. F., Gross, D. and Loftus, J. J., A method for measuring

surface flammability of materials using a radiant energy source. Proceedings of the American Society for Testing and Materials, Vol. 56,

1437-1452 (1956).

[7] Parker, W. J. and Long, M. E., Development of a heat release rate

calorimeter at NBS, ignition, heat release and noncombustibility of

materials, ASTM STP 502, American Society for Testing and Materials,

135-151 (1972) .

14
[8] Loftus, J. J., Gross, D. and Robertson, A. F., Potential heat--a method

for measuring the heat release of materials in building fires. Proceedings of the American Society for Testing and Materials, Vol. 61,

1336-1348 (196].) .

[9] Lee, B. T. and Parker, W. J. , Fire buildup in shipboard compartments--

characterization of some vulnerable spaces and the status of prediction

analysis, Nat. Bur. Stand. (U.S.), NBSIR 79-1714 (1979).

[10] Fire Performance Requirements and Approved Specifications for Interior

Finish Materials and Furnishings (Naval Shipboard Use) , Military Standard

1623 B (SHIPS) (Nov. 14, 1975).

[11] Building Materials and Structures, NBS Report BMS 92 (Oct. 7, 1942).

[12] Lee, B. T., Quarter-scale modeling of room fire tests of interior finish,

Nat. Bur. Stand. (U.S.), NBSIR, to be published.

[13] Castino, G. T. , et al.. Flammability studies of cellular plastics and

other building materials used for interior finish. Underwriters Laboratories, Inc. (1975).

[14] Gross, D., Loftus, J. J. and Robertson, A. F., Method for measuring

smoke from burning materials, ASTM Special Technical Publication No. 422,

164-204 (1967), American Society for Testing and Materials, Philadelphia,

Pa.

15
8. APPENDIX LABORATORY FIRE TESTS

8.1 Ease of Ignition

The ease-of-ignition test [4] measures the flame exposure time required

for the onset of fuel contribution of materials. Two specimens 14.0 cm

(5-1/2 in) wide and 15.2 cm (6 in) high face each other 50 mm (2 in) apart. A

methane diffusion flame passes between the specimen surfaces and extends about

25.4 cm (10 in) above them. By subjecting up to six pairs of specimens to

different exposure times the minimum flame exposure time required to produce

a contribution of fuel from the specimen is determined.

8.2 ASTM E 84* Flame Spread

The ASTM E 84 tunnel test [5] measures the flame spread performance of

the specimen material relative to that of asbestos-cement board and red oak

flooring under similar test conditions for a duration of ten minutes. A

50.8 cm (20 in) wide and 7.3 m (24 ft) long specimen is horizontally-mounted

in an overhead orientation in a 7.6 m (25 ft) long test chamber. The fire end

of the tunnel is provided with two gas burners delivering flames upward against

the surface of the test sample. An air intake port 7.6 cm (3 in) high measured

from the floor level of the test chamber is provided at the fire end. The vent

end is fitted to a 40.6 cm (16 in) diameter flue pipe. Changes in smoke density in the latter is monitored photometrically. A thermocouple is also

mounted 2.5 cm (1 in) from the sample surface, 30.5 cm (1 ft) from the vent

end

.

Results are given for flame spread, fuel contributed and smoke developed.

These values, obtained from burning the test material, represent a comparison

with those of asbestos-cement board expressed as zero and red oak flooring

expressed as 100. Flame spread classification, FSC, is determined as follows:

(1) For materials on which flame spreads 5.9 m (19-1/2 ft) in a time, t, of 5-1/2 min, or less, FSC = 550/t.

(2) If the flame front spreads 5.9 m (19-1/2 ft) in more than

5-1/2 min, then FSC = 50 + 275/t.

(3) For materials on which the flame spreads less than 5.9 m

(19-1/2 ft) but more than 4.1 m (13-1/2 ft), FSC = 50 + 4.6 d

where d is in meters, and FSC = 50 + 1.4 d where d is in feet.

(4) When the extreme flame spread distance is 4.1 m (13-1/2 ft) or less, the classification is FSC = 16.8 d for d in meters

and 5.1 d for d in feet.

The value for fuel contributed is derived by calculating the net area under the time-temperature curve from the thermocouple near the vent end for

the test material and comparing this area with the net area under the curve

for untreated red oak flooring.

The smoke developed during the test is determined from the time dependent

increase in obscuration of a light source due to the smoke in the vent pipe.

The smoke rating is derived by calculating the net area under the timeobscuration curve for the test material and comparing this area with the net area under the curve for untreated red oak flooring.

•k A new method has been adopted for calculating the flame spread, but the above

method was used for the materials tested on this project.

16
8,3

ASTM E 162 Flame Spread

The ASTM E 162 radiant panel test [6] requires a 15 x 46 cm (6 x 18 in)

specimen, facing and inclined 30 degrees to a vertically-mounted, gas-fired

radiant panel. The energy output of the panel is controlled to be the same as that from a blackbody of the same dimensions operating at a temperature of

670° C (1238° F) . Ignition is caused by a pilot flame just above the upper

edge of the test specimen and observations are made of the progress of the

flame front down the specimen surface, as well as the temperature rise of the

thermocouples in a stack supported above the test specimen. The test is terminated when the flame reaches the end of the specimen or in 15 minutes, whichever time is less. The flame spread index, Ig, is computed as the product of

the flame spread factor, Fg, and the heat evolution, , or Ig = FgQg, where

F

s

1 + and Q

s O.lAT/6

The symbols ta to tis to correspond to times in minutes from specimen exposure

until arrival of the flame front at a position 7.6 to 38 cm (3 to 15 in)

respectively, along the length of the specimen. The value of 0.1 in the relation for the heat evolution is a constant arbitrarily chosen to yield a flame

spread index of approximately 100 for red oak. The quantity AT is the observed

maximum stack thermocouple temperature rise over that observed with an asbestos-cement board specimen, and 6 is the maximum stack thermocouple temperature rise for unit heat input rate to the calibration burner.

This test procedure has been adopted as an ASTM standard method for

measuring the flammability of building materials. The flame spread index value

is zero for asbestos-cement board and 100 for red oak flooring.

8.4

Rate of Heat Release Calorimeter

The heat release rate calorimeter [7] measures the rate of heat generation

for materials exposed to radiant fluxes up to 10 W/cm^(8.8 Btu/s/ft^) with a response time of a few seconds. A 11.4 by 15.2 cm (4-1/2 x 6 in) specimen, up

to 2 . 5 cm (1 in) in thickness, is oriented vertically in front of gas-fired

radiant panels lining three sides of a combustion chamber. The radiation comes

from the surface of these panels where temperatures may be varied between

627° C and 1027° C (1160° F and 1880° F) to produce the desired irradiance

level on the sample. The edges of the specimen are shielded by an insulated

holder. Air for combustion of the sample passes up through the porous floor

of the chamber.

The fast time response of the calorimeter to the heat leaving the front

surface of the specimen is achieved by maintaining the instrument at a constant

temperature, thus overcoming the thermal inertia associated with the heating

and cooling of the calorimeter walls. The constant temperature operation is

accomplished with an auxiliary burner whose fuel supply is regulated by an automatic temperature controller. An increase in heat due to the burning of

the specimen is then compensated by a decrease in the fuel flow rate to the

burner. The measured decrease in the rate of flow of the fuel is then recorded

as the rate of heat release of the specimen.

8.5

Potential Heat Test

The potential heat test [8] provides a quantitative measure of the total

heat release under typical fire exposure conditions without regard to the rate

at which the heat is released.

The heat of combustion, , of sample of the material, measured by an oxygen bomb calorimeter, after it has been exposed to a "standardized fire"

17
(two hours in a muffle furnace at 750° C (1382° F) ) is compared with the heat

of combustion 0^ of an unexposed sample. The potential heat Qt/ is given by

Qt = Qm

- R Q,

where R is the fractional weight remaining after the exposure.

Determinations may be made on simple materials, or on composite assemblies

of materials from which a representative sample can be taken and pulverized

into a homogeneous mixture.

18
t LEFT BULKHEAD

station Instrument

1

2

34

5

6

7 to 10

7 8,10

9 11 to 13

Vertical strand of thermocouples extending from overhead

to deck

Vertical strand of thermocouples extending down from top

of doorway

Pitot tubes along length of doorway

Gas sampling in doorway

Phototube for horizontal smoke meter at top of doorway

Light source for smoke meter

Thermal flux gauges at one or more of these locations

On deck

One-fourth of distance down bulkhead, flush with

bulkhead surface

Flush with overhead

Flashover indicators (crumpled newsprint) on deck

Figure 1. Plan view of compartment arrangement showing locations

of ignition burner and instrumentation

19
Figure 2A. Quarter-scale compartment fire test prior to ignitionj
z

i

I

21

Figure

3.

Top

of

doorway

air

temperature

histories

for

several

prototype

fires

and

model

tests

using

lintel

III
PERCENT

DOORWAY

HEIGHT

[3)

PERCENT

OVERHEAD

HEIGHT

lOOi90

80

70

60

50

40

30

20

10

0

TIME OF

PEAK TEMP

(MIN)

0.50

0.78

0.67

I .62

7.8

9 .

A

A

O

J I I l_l I I I I I I I I I l__J

100 200 300 400 500 600 700 800 900 1000

Lgure 4

TEMPERATURE. °C

Compartment air temperature profiles at time of

peak doorway air temperature

TEMPERATURE. °C

Figure 5. Doorway air temperature profiles at time of peak doorway air temperature

22
001

1HOI3H AYMSOOG INSDVSd

IHOOH AYM)IOOO INaOtlid

I

Figure

6.

Doorv/ay

velocity

profiles

for

full-scale

tests

FS-1

and

FS-
PERCENT

DOORWAY

HEIGHT

VELOCITY m/min

Figure 7. Doorway velocity profiles for full-scale test FS-4

24
100

0 1.0 2.0 3.0 4.0 5.0

PERCENT CARBON MONOXIDE

Figure 8. Carbon monoxide concentrations along doorway

at time of peak doorway air temperature

PERCENT OXYGEN DEPLETION

Figure 9. Oxygen depletion profile along doorway

at time of peak doorway air temperature

L

25
Compartment showing gas burners in back corner

and in one frame bay

Compartment showing doorway and gas burner

in frame bay

Figure 10. Proposed submarine fire test compartment with

frame bays

26
Table

1.

Materials

used

in

the

compartment

and

laboratory

fire

tests <1) u

a. c ouo

<0) >

cs -C

-o

-oX so

(-H ON

•o^ 4J n c u a. a •:) 'H > U N-4 o. ^uOo

s: a+

Si aO oc ^cc uo -« • o < <0 • Q.

:z t/5 if

27
I wuw

0>

01 T3oeu

COau

0) 4Jc3oo

-oc

CO

(A0)

(U

CO0

0513O

?>^ u

<03w

CM

(U

CO H 1 s:

to is

m lA 3 *J C o r*«. CM O o O'

O

O o 00 o o o O e —1 O iH D O O L> 30 rH o o o O

•H *H S H 4-1 X

0^ C 0) o o '4-1 > 4J

Om r-*.

O CM CO r-- CM c r*. o m r-» r- r-- vO

4^ XU 8 8 8 8 8 8 8 8 •H 01 05 tH a O O rH CD O O O rH c a CO T)

00 -H ^ C A M 4J »4-t •H O o CM 00

O CM

00 Q> H c m o lA CA r>. r*- X 00 rH vO 00 O CM lA

•H 0 a O ^ O l>»

d

dO o CA rH r-- sD (O' lA

x

H 4J

CM

*' >.

H

O lA lA fH lA vO CO

O 00 rH r-- -S'

X 3 • o r-«. 1 O' CA 1—

00 (A O' <7' 00

O O' 00 rH 00 CM

(0 a m

m vO CM lA -O' vO rH CM lA CM CM (A CM CA

3C o a O 0) *0 4J

OO CO o CM CO

O

O

O

0)

H c m r«. O' lA

O r- r-. vD r- r— lA r-. r-» CM O' a

•H 0 a o o o O o OO

O

O CM sO r- r-. CA 'O

H 4J rH u

*H i-H •K CO H

•<r r- CO <?' vO r*- <r

O rHO \D CM CO P- -S'

X

u • o -sf CO CM

O

O CA CM rH sO O' CM ir

O

CO 0) a vO vO (30 CM r- sD CO CM -O' vO CA CA -S c^ -S' s a a a 0) 3 4J

to e ay lA

m o CA (A CA P-. a 4J 3 c <r O' lA s£> P-. <r

0) CO 3 V4 •H 8 8 8 8 8 8 8 8 a ^ o o a CD o o CD o o O

•H <4-< 0 H *0

V c CM CM CM CM CM CM CM CM <p -S' -s o 0) 0) -H u X vO vD X X X vD vO O' O' O'

05 C 4-> 3 CM *3 *3 CM T3 *3 *3 CM Tl ’V T) *3 T3 -S' *3

<0

u 3 v£> 0) 0) vD 3 3 3 sO 3 3 3 <J' 3 3 O' 3 O 3 C O 1—

rH rH rH rH

X 00 05 3 3 3 3 3 3 3 3 3 3 3 H U U U U U U U O O U U W W CO CO CO CO CO CO CO CO CO

P-- P-. CO O 00

O' CM O'

oO p>. p^ r- r- r-. 1 1 1 r-- c O O O CO 00 00 o < O O

•H CM CM CM 3 3 3 3 3 3 3 3 O' <7' O' CM

JJ >. 1 1. C C C C C C C C 1 1 1 05 05 05 1 CO < < < n n 0 O o o n 0 O o o 4J 4J 4H < 0 2 2 2 2 2 2 2 2 3 3 3 u 05 05 05 05 05 3 0 O 0 3

4J 4J 4J 4J 4J 4-1

UUU 4J 3 3 3 3 3 3 a a P> 3 0 O O O O O o 0 O 0 U O CJ U CJ U H H H CJ CM CM CM CM CM CM CM (A CM CA co

•H

4J

CO CM CM CM CM CM CM CM CM CM CM CM CM CM CM CM CM

t-H CJ CJ

u

U

UUU CO oa CQ PQ CQ CQ CQ CQ 3

05C

*0 3 -3 *3 •3 •3 •3 •3

0) 3 3 3 3 3 3 3 3 r-4 3 rH rH 3 rH 3 3

CO 4J

N 3 N 3 3 N 3 3 N

N 3 3 X U •H O U •rH U U •H U U -H U

vj OOW *3 CO 03 'V to CO 05 *3 CO CO 0) CO CO

O -H 3 3 3 0 0) .H rH cn rH (A vO CA

X CA vO CA

QX ^3 0' 3 O' CO rH 3 O' 00 rH O' 00 (O' 3 U . 3 U 3 U 3 3

tv. CO

O t41^ CO

OO CO

OO tv.

O o tv,O

Qi 1—

rH rH rH rH

CO 1—1 -J' <H -O' sf -cr rH -T -3- rH -S' -S' rH -S 3 ^ 

3 3 3 3

cn tv. ^ f-l Ch rH rH rH tb rH rH rH Ch rH rH rH

4J 1-H CM CA -3- lA u CO sD rO CO -0- CM <A CO o <r CO H [v. CM Cb CM CA (v. rH CM (A -S' lA -S

05 05 CO CO

<a 0) s s

28

below

center

of

overhead

below

top

of

doorway
Table

3.

Sununary

of

model

tests,

scaled

height

above

doorway

(lintel

I) r X 0 CO U

m r- in r -u C 0 0 0 m Cv. 0 O' 0 <r CO vO 0 0 0 Cs. CO x>

00 c 3 C E 0 0 X> 0 00 0 0 0 rM 0 iH rH 0 0 00 00 0 rH rH E^ s —

l-H •H 1—

fH fH

<i)

u

u •K C ^ o •K 0 VM > 4J m CO CM 0 r** CM

tH

O 0 CQ c r>* 00 O' Me Me 0 vO v£> rH

u J= o iH 8 8 3 8 8 • 8 • • 8 Me Me • • 8 8 8 • • • 01 CC *H E 0 0 0 Mc Me iH 0 0 rH rH c E nj •« s,^ A

00 r-l c

t—

4-1 *H

CM CO CM 0 C- CM

0» E-* C f-H CO 00 O' 00 O' 00 vT vT 0 MJ 0 sO rH E •H 1 1 1 •H o E r>. 0 0 0 0 iH rH rH 0 s£> 0 0 rH rH H .u rH

<N 1 H

door

rop• tn O' in CO 0 0 sD CM O' 'O O' 00 0 0 0 O'

0)

O 1 Cn, rH eH 1 0 CO rH O' MT vO

m <r CO Cn. CM • 4J o iH fH CM CM CM 'O vO fH vO m <r m CM CM CM m in

Max ay3 m CM

m in in

0)

H C 0 0 r>. n*. 0 in O' <r 0 O' in 0 0 so CO E •H 1 1 1 *H O E i-M 0 r>. 0 0 0 0 rH 0 0 00 O' 0 0 rH Hu H

0)a • Q. a 0 m vD CO r>*

m <r rH r>*m O' in 0 rs. vO r«. 3 E o 0 CN 00 O' 0 CM CM CM m 0 rH m 0 0> o CM CM CM sO CM CM Cx rs. vO CO MJ* r>» r>. • u >s«/ V X

(Q

U S -H

CO

0)e

CO CO •—« 5u

m r>. 0 CO

m f>- CM 00m 0 c r>. vO 00 vO 00 CO m m CM 0 0 •H 8 8 8 8 8 • 8 • • 8 • • • 8 8 8 • • • u -o E 0 0 0 0 0 0 0 0 0 rH V

0) 4J E 3

*H 0 H

0)UU

0) 3 0) 0

0) «4-« C Cfl o u3 C '3 O' O' O' a^ O' O' CJ' O' O' O' CJ' O' <J' O' O' CJ' O' p' O' u 0) 0 K

4J *H CO CO CO CO CO CO CO CO CO CO CO CO

mm in in in in

4J CO CA 4J

<d ^4 COoA e X 00

•H

r*- r«.

r««. r>* r««. 0 0 r*«. p>» 0 0 0 fO CO 0 CO r**. 0 0

CM CM CM \D v£> CM CM vO CM CM CM

CO < < < 0 0 < 0 c:!) < < c

•H (A (U CA <u <u CA CA CA CA 0) CA CO CA CO 0) CO 0) o» 4J 4J c 4J C c 4J 4J 4J 4J c MJ 4J 4J u c c a u C c

CO <0 0 CO 0 0 CO (0 CO CO 0 CO CO CO <0 0 0 0 (0 0 0 0 0 X 0 z z 0 0 0 0 z 0 0 0 0 z z z 0 z z

{-)U CJ 0 CJ CJ

u CJ CJ CJ CJ 0

CM CM CM CM CM CM CM CM CM CM CM

(A CA CO

(A CA CO c <0 <0 (0 0 rM rH

•w oc 00 00

4J

cO CM CA CA CM CM CM CM CM CM CM CM CM CM CM CO CM CM CM CM 3 3 0 CJ u U CJ CJ oa OQ CQ OQ *o 3 U CJ 0 CQ 3 0 0 0

0)

Uu

u c Xi X Xi M •H •H •H

Pu Pu Pu

(A CM CO in lO r*^ 00 O' 0 CM CO 'J'

m Cn. 00 O' 0

0) fH rH rH rH rH ^H rH rH rM CM H

29
O'ICJBo

00d

C' cn ON vO

CO

ON

M 1 • • • • M 01 CM O o & iH oo

TO

HI "doS

V4

0) uu§ ON CO VO o • « • 1 00 00 VO

01Bo

cn

<u Xi

01>o

viol iH

n) H

<u iH 0) Q)

CO

N

N

O •H •H W W VO o CM

iH iH

m CO CO rM CO ON i-M 0 0 rH 0

P4 §uoo

"O0> X

0-1o

B.o

(U 4JC

•H

I-)

4C -S *C 60

4J s •H a u a 0)

<u 6 u SC Q u s-/

4-1 >s

rH

B 4C 01

O ,12 60 4-1 &

•U 4J •H •o C a a <U •H o

•H 0) SC S o A o >> Sv TJ rH td 0) •a

<U a a 0) rM U C b rH

CO a o o CO O •H o o o W o Q CO

01 X

01uB

nJ 4J

(0 •Ho*

30
Table

5.

Summary

of

model

tests,

1.4

times

scaled

height

above

doorway

(lintel

(II)

o

I

CO3 «u

<u 00 c

i c V

*rH S

cs O IH O O

d d

o o o

m CM

vj- O' m

o > 4J /-s *H O O <0 c

4J j: o *H

•H 0) CO *H s

c e 03 "o

00 *H fH c M U 4-1 tH

CM r-O

O ^

8 8 8 O

m CM

00 m

.aH

CM H

O

CM 00 O

f>» 1-H O O r-> o o o rH m

».3’ in 00

u

o

0

•o

Xs

CM H

cd

o m «H 00 00 o 00 lA 00 m

CM m CM CM

00 r>- cn

iT\ en <t

CM CO cn

CM r>. fH in m in

•-H ^ H

a

•H O H 4J

CM CO O cn

r- r- C' cm r»* o

cn O O CM O m Mj* 00 cn

sfi r--. <T m o o

CM \0 O 0-3* ^ CO •—MT m <r o .-I (T' CO MT cn m -j-

\D cn ^ <n

V.0 r>.

fd

a sn

Cd <d

o

o o

4j *d

0) u

B 3

4J cd CO 4J

<7> O'

cn <n

o> cn

fio cd Z oO

CM

CTN ON

in m

rH *0

JS >N o M

00 00 § §

o o

u u

.o ^

•H *H

OU (L,

o

r-C *0

U3 >S O

Cd "o 5 2

Cd (d Cd Cd Id (d O »H O tj t-H

o

.H 73 X X

O jrf

5 2

31
Table

6.

Model

tests

of

fire

barrier

coatings

0 w U ‘H3 4J

<U &0 C a c Qj •H >H a H u

X

<u

t-i M

C <1)0 O > 4J

•H o O <0 4J x: o

•H <U CO *H c a <0 T3

&0 *H fH C M iJ CM ‘H

CNi

I H

kio • 0 a

-o a

0)

<D H

a

*H O H 4J

M H

•1) a •

X1

d)a

^ (4 .H a

M-l b

O

o o

4J 'O

0) 4J a 3

•H o H

CO 4-) a -c ^ &o

f'J o

m o

O m

O vO

r*» \D

vO 00

00 O

ro m

O

CNJ o

CM m

CM

ON 0> m m

00

o m o o

d rH ^ o

or- moN O CO lA 00 -3-CO lA -J -y CO ^ 00 CMCA lACO CM r- vO CM

CM lA

CM -O’

r- CM On cm

vD

o o^ vO r- o o CO rO' CM CM 00

-d- lA CM 0^ CO r- nO CO

o o

•H CO

o\ o>

lA lA

CJ u o u

CO c/5 CO to

o o o o

0\ C> On On

lA lA lA lA

CO O

-dr d

CM CM «0 ON

-4* ON

CM ON

lA CM

00 CM CO r«.

O riH CM

nO -O

<4 <4 o o

CJ O

CM -d* W I I *J <3 O

<4O CO (0 U 4-t 4J CL (4 (4 O O O H U CJ

-d* 00

<r ON

I I o o

O O O O MT

CM CM CO

O 4J o o

O. <4 O O

O 6 CO -d* ^ H O CO rM U

ICMCMCOCMCOi-HN<3 cMCMCM

(0 so

4J < iJ < ^ I <0 (4 <4 0

O (0 O CO O

(4**M0^ (0 0<c4 CLc4 0«(4 OOeSi OOOOOOO OHOCJHCJHCJHU

so CM CO CM CO CM i-M

4J 4J C 00 4J

t4

c4 c4

CJ O

CO CO

OS ON

lA LA

00

I 00

•H 4c r- M 4( OS O 4C I 00

i-» *0 O 00 r- X >> -o r-. 00 O ^ to CO On OS

f-M iJ NO I I 4J <4 <4 I O O

<4 O O

O *0 CJ CO to O 0) I <U 4J 4J

Q. 4J (4 <0 (4 O t4 *H O O O H C3 S O CJ O

iH CM «H CM CM

32

*A1400

Coating

separated

from

overhead

in

one

large

flaming

sheet.

**0-987

used

only

on

overhead

and

upper

half

of

bulkheads.

***Sections

of

the

chlorinated

alkyd

paint

layer

on

overhead

fell

off

beginning

at

15

sec.
Table

7.

Sununary

of

model

tests

1.8

times

scaled

height

above

doorway

(lintel

III)

o (0 4J *H

d) 00 c

B G ^ -H S

E-* 4-» X

Q)

(U O

M-l > 4J O O «

pC O

0) CO •H a <0 'o

) *H rH c

(U H

5 o H u

(U H

a

*H O H

Ui H

4)a • a cu 3 a

<u

0)a

CO >%

(0

M-( ^u

o o U o

4) a

•H 3 H O

(03O CO M (0 5.3

PU 60

33
Table

8A.

Ease

of

ignition

and

flame

spread

properties

of

materials

used

in

compartment

fire

tests

CO CS O nO

CO 00 I II cn I I CO (N ..y O O' vO

I til

CM vO CM cn o O

^ rH cn O' CM rH

O

sO m• I II

\0 o o

I I I

c^ 00 P-*- O O

rH CM m CM CM «H O CM vO O O O

iH fH O -O CM rH

I III

O O' o >o

'O 00 I vO I O' CM I I cn O' in r-t

iH CM 'O o

I I CO CO ill I "O- o I l>> sO 00 O

I I I I

<U -H o

3 »-i > ' iJ < III I I I I I I

I I I I

III I I I I I

o o

O' o o

CM 00 o o o

O' O so o o o

CO .» O' o o

00 CO

CO -o- iH CM CM

CO lO in

r-l CM CM

Soo 0r>. Sc ooooo ooo ui

CM O' O' O' O' <

I I J CO 1 CO I O' <iOOCMOCMOO<

OUOOOOCJO

inmm um Mm Mm m vair-tcMCMaicMaicMaicMO) ceooo>o>o>o> VO) oo*>>o«o>o«o a c zzooo oo o o o zz

p** O r** S o p*' CO 00 o

CM CM vO O' ^ o CMo

a a s a •

o o o o

d d d d

333

O O 33 oa CO CO CO 0Q o ca o <0 o

00 -H 00 00 *M 00

34

*E

84

specimens

bonded

with

Armstrong

520

adhesive

on

0.64

cm

asbestos

board.

Three

tests

conducted

on

each

material.

**Tests

conducted

at

Naval

Ship

Research

and

Development

Center,

Annapolis,

Md.,

except

for

data

in

parenthesis,

which

were

measured

the

National

Bureau

of

Standards.

All

E

162

specimens

bonded

with

M-30

adhesive

on

0.64

cm

aluminum

plate.

Three

tests

performed

each

material.
Table

8B.

Heat

release

rate

and

potential

heat

of

materials

used

in

compartment

fire

tests

U

CO<u /-N

eg CO in cn vO vO

iH a fn vO vO in CO CM CM

CO

U • 1 • 1 • 1 1 1 1 • 1 •H m o o o o d 4J *-) c J.S <u 4Jo

Oi

0) • (U &0 u > CvJ cd a vO 00

m 00 CM in rH o o 4J a 1 • 1 1 1 1 1 • vO 00 m <r vD r>. rH c 3 V X -H

•K eg E V s

COCO

lU iH t 0) (U c)0 u c > eg O efl a 00 00 CO c^

m <r o 4J O 1 • 1 1 1 1 1 CO • • vO o \o m ON 00 00 rH

01

X c 3 i-HV i s

M-lo

(U 4J eg 3 ,2i5 a 00 CM cn o <r r*^ K CO O * • • • • • • 1 • 1 1 1 1 1 (U o m On m CM CM o 00 rH

Oi 3 iH iH rM f-H fH rH

'w'

00G

•H 00

r>* o rH r>. o 00

00Om o m 00 rN. 00 CM CM vO O CM CM vO c^ c 1 1 1 f CO 1 1 1 •H o c « o a < « o o o

CO

CO a a a a a a a a a a o CJ O CJ O u O a O O o m in m m a

in

m inm

m

Q) 0) 0) CS 0) i-H rH rH (U <D rH rH rH CM CM c c c o G O o o G o G o o o o o o o o • o • • • o • o 3 Z 3 O 3 o o O 3 o 3 o o O o d

CO

CO

(UG /-s CM r**. r**

mmm

.2 a o a CM CM CM CM CM CM CM CM CM CM CM

•H 'w' H

rH

CO CO •H o 3 to M CM CM CM CM CM CM CM u O CO

(U tf) PQ o o u CJ o tH CO o ^ rH ^ 00

CLi

0)uo

00oX

<D

35
Table

9A.

Ease

of

ignition

and

flame

spread

properties

of

other

submarine

insulation

materials

DO o r>. 05 o m CM rH cn > 00 cn 1 o 05 1 P^ o i 00 >7 rH i rH 1 TO < rH rH in 00 P-i. <d

0) (0 U M a X 00 MT 00

m 05 cn sO -7

0)

X 1 CO vO 1 CM

m 1 rH rH 1 rH 1 1 s rH cn rH

1) *0 B C

cd *H

rH rH rH * 3 s£) 50 CM O 05 00

CM •H -d* CM 1 r>. 1 in sO 1 05 rH 1 i s »—

rH CM

i-H w

OJ) >

r>. c^ CM rH >7 cn ' cn -7

g fO <35 00 o * cn rH rH CM w T3 iH •H CM rH CM o m c Cd

OJ (A

V4 C&4 •

rH

O' fO

mOO cn o 05 '

->7 >7

0) i-i cd r>. CM o vO ' in O' * cn

m rH ^7 0 S 1-^ CM CM 50 rH 50 in p»* 0) U rH 9 0

r-l M-i 3

ir» lO 1<75 in , CM 'O 1 cn «7 1 CM 1 O 1 •H O m 50 sO in 05 P>. rH rH

z: rH rH

<u oo o cn rH cn 00 in sO ^7 o > fH 1 <7v rH 00 1 P>. 00 1 ps. o t «7 1 O 1 s < fO v£> CM cn p^ cn ps» >7 rH sO CM w rH

'V

(U3

0) 05 CO CM i-H CM cn 50 cn

m

O in 3 U > CM 1 iH rH rH 1 rH 1 rH rH 1 rH 1 CM 1 b 4-> < K c0

00 CJ ug to

m 1-H CM CM vO 00 sO in rH

c/5 > O 1 cn 1 cnm 1 CM «7 1 cn 1 cn 1 < -3 <

cd

<S) ua X <75 p«» cn 05 05 05 rH 05 sO HC

CO

u rO r>. 1 cn ( cn in t cn MT 1 cn 1 1 1 CO s

<U

b 9

cd rH

b* 3 fO CM rH 05 cn 05 50 05 cn HC

•rt scn ' 1 cn cn ' CM >7 ' CM cn 1 cn 1 1 1 c0

•H 1-^ U O C

•H 3 O c <4H *H

01 4-> M U 3 o r*.

m 00 CM 05 CM

m sO CM

O 01 1 iH 1 rH 1 rH 1 1 I 1 CM

<4-1 <4-4 *H CO O Wi

0) ij

a> 9 3

(fl •H o

cd

HO

bi

(0

(0

<U "gu

cn 50 vD C»5 cn P>. cn -7 cn

mm cn cn cn cn o rH CM CM CM CM rH CM CM CM CM rH

•HXH

P>. P^ pv p>. r>.

O

O o o o o

oo

CM CM CM CM CM CM c < < < -i < <: 9 a 9 8 9 9

cd o u

u o uu

CJ

m

mmmm in

0) 01 rH 01 01 01 rH 01 01 rH 01 01 01 rH 01 3 3 O 3 3 3 o 3 3 o 3 3 o 3 o 3 o O O 0 0 0 O 0 O 0 0 0 z z o z z z o z z o z z o z o z o

i-H(d •H

<U 53 \D sO <75 vT >7 <f so so so p^ p^ 00 00

4J

Cd S < < *< CO CQ CQ

O CJ CJO o CJu

u o CJ

36

*E

84

specimens

bonded

with

520

adhesive

on

0.64

cm

asbestos

board.

Three

tests

conducted

on

each

material

except

for

A9

and

Co

wh:

had

one

test

each.

**Tests

conducted

at

Naval

Ship

Research

and

Development

Center,

Annapolis,

Md.,

except

for

data

in

parenthesis,

which

were

measured

the

National

Bureau

of

Standards.

All E

162

specimens

bonded

with

M-30

adhesive

on

0.64

cm

aluminum

plate.

Three

tests

performed
Table 9B. Heat release rate of other submarine insulation materials

Rate of heat release*

Material Thickness Coating Peak Max. one min . avg

Max. three

min . avg

(cm) (W/ cm^ ) (W/ cm^

(W/ cm^

A6 2.6 None 11.2 8.9 8.4

B4 2.7 None 8.6 7.2 6.7

C4 2.4 None 14.5 12.1 11.1

C6 2.5 None 10.9 8.2 7.4

C7 1.3 None 12.8 8.4 6.6

C8 1.3 None 10.3 6.6 5.1

*With exposure of 4 W/cm^

Table 10. Comparison of compartment

with three different

air temperatures for fire tests

doorway openings

Test

Doorway

height Insulation

Source

setting

(kW)

Max. interior

upper air temp.

(*C)

Max. doorway

air temp.

(“C)

Flashover

t imes

(min)

4 Scaled C2 3.9 216 215 0»

5 Scaled C2 3.9 293 213 CD 16 Scaled C2 5.9 410 240 CD 17 Scaled C2 5.9 477 240 CD 22 0.93 Scaled C2 3.9 707 585 0.72

33 0.86 Scaled C2 3.9 604 451 0.78

10 Scaled B2 3.9 221 196 CD 19 Scaled B2 5.9 756 579 1.17

24 0.93 Scaled B2 3.9 410 288 CD 34 0.86 Scaled B2 3.9 646 500 1.62

37
Table

11.

Concentrations

of

some

combustion

gases

at

top

of

doorway

u

c ^ o o

cj o

CNicomtHiHO<-iOf-(roocscsHf*^*>4'r-icMf-iCMiHr^^mcn«7cocnfOirt

PO iH CM <n cn ,H CM

•K o e

c a u o a

sc CJ

o o o o

O O O I o CM CM CM CM V V V V

o o o o o

I o o o o o CM CM CM CM CM V V V V ooooooooooo

OCMCMCMCMCMCMCMCMCMCM fHVVVVVVVVVV

o o o o o o

o o o o o o,

CM CM CM CM CM CM V V V V V V

Me • « u S z G a u o a XU

oooinmmoo O <r CM V V VCMO

sO iH momoooooiAmo vOvcmomt-^vov vcm

sO vD A A mmooooiAommo VVrH-*d“CM VOVV-4*

A

CO 00 cn CM OvOOOOOOOcnr^COsOvOOOOOOOOOOOOOOOOOO

iHOiHCMWOi-»CMmOOOOfHfHCMm^mON^«noOiHCMir>iH'*d'iHuOOO

3

O

' '

0^ O' o>

CO CO lA

< 55 <

T3

.5* 00O'

I o

>© CM CM CM CO

CO CO

00 XO CO

cn

O' O rH 'o mm

38

*

Refer

to

tables

5

and

6

for

more

complete

description

of

coatings

**Gas

concentrations

estimated

with

colorimetric

Indicator

tubes
Table 12. Comparison of fire buildup in full-scale and corresponding

quarter-scale compartments

Test Test Doorway Doorway Ignition Degree of

Arrangement No. Lintel Height Setting Fire Buildup*

1. FS-1 - Full Size Low Flashover

6 I Scaled Low Flashover

23 II 0.93 Scaled Low Flashover

2. FS-2 - Full Size Low Flashover

4 I Scaled Low 215'’C 22 II 0.93 Scaled Low Flashover

33 III 0.86 Scaled Low Flashover

3. FS-3 Full Size Low Flashover

10 I Scaled Low 196°C

24 II 0.93 Scaled Low 288“C

34 III 0.86 Scaled Low Flashover

4. FS-4 — Full Size High 297'’C 44 II 0.93 Scaled High 288‘’C 51 III 0.86 Scaled High 299°C

5. FS-5 - Full Size High 287®C

46 II 0.93 Scaled High 324‘’C

*Based on ignition of flashover indicator and doorway air temperature

Table 13. Flux measurements at time of peak doorway temperature

Test Time

(min)

Deck Upper left bulkhead

(W/cm^) (W/cm^)

Upper right bulkhead Overhead

(W/cm^) (W/cm^)

FS-1 0.50 1.73 - - - 23 1.07 2.00 4.9 5.5 5.0

FS-2 0.50 2.95 _ - - 33 0.78 2.53 4.8 7.6 5.4

FS-3 0.67 2.0* - - - 24 3.10 0.28 0.74 0.67 0.66

34 1.62 2.52 5.6 6.7 5.2

FS-4 7.8 0.19 _ - - 44 6.0 0.46 0.75 - - 51 9.2 0.56 1.5 1.3 1.4

FS-5 5.5 0.17 0.59 0.58 0.63

46 6.8 0.36 — 0.62

*Also the value at 0.77 min when flashover occurred.

39
Table 14. Calculated mass balance across doorway

for three compartment fires

Test Time

(min)

Mass flow in

(kg /min)

Mass flow out

(kg /min)

FS-1 0.25 3 46

0.50 30 79

FS-2 0.25 2 39

0.50 18 61

FS-4 0.25 3 15

0.50 28 31

1.0 31 25

5.0 43 47

8.0 39 52

Table 15. Comparison of measured model and prototype inflow air velocities

near bottom of doorway

Time

(min)

Model*

Velocity

(m/min)

Prototype FS-4

Velocity

(m/min)

Velocity Ratio

Prototype/Model

0.25 14 6 0.4

0.50 16 34 2.1

5.0 20 49 2.5

6.0 23 55 2.4

icAveraged values from tests 44 and 51.

40
Table

16.

Carbon

monoxide,

carbon

dioxide,

and

oxygen

concentrations,

and

smoke

measurements

at

doorway

at

time

of

peak

doorway

temperature

>> rH

(U

•K >

•H

0) rH r^ 00 00 o 00 4J *0 • <r vO CN <r o CM o c 2 Q • 1 • 1 1 « • • 1 • • 1 0) cd a • CM CO ^ ON iH a W o (0 ,H

(U (U iJ "OO

•> a

rH

/-s CO 00 00 c

CM • 1 1 1 1 • 1 • 1 1 • i 'd *H o cn CO o o o c iH CM CM a a 0

•HU C CN

CQ o CM iH rH cd • U o 00 o o o q o Sm/ • 1 1 1 1 • 1 • 1 1 • 1 m

iH a 'o

?s

G

XI CO O

X)

B

O

/-*\ fO

O

u ^ CM o o 00 O* CM o • 1 • 1 1 • 1 • 1 1 • 1 • vO vO iH CN o d o rM fH CM •H * IH

CN rH

O

<U c o vC CM 4J • • CO o CM /-N vO <r CO CM CM d lu <i) •H o • 1 • 1 1 • 1 • 1 1 • 1 -H a. o. XI

4J o fH 00 rH fs >, ao

(d rH iH XI XI c u >» O O (U o Cd MJ W iH

l-J /-N <“ CM rH

OO

{mu ^ x: o CM iTi Ov o O 0 o. a 4J o s-/ • 1 • 1 1 • 1 t 1 1 • 1 o cd (n CO CM *d d d a.

•H *H a <u O rH rH J«!

01 0) 0

MM

H 4J s

i-H c> CO CM CO ^ CO

CM iH

m o vO iH CN CN CM CM

O 1^ 6-S-S'^

Q /

f-H CO sO iH CO vO NO CM NO in o

fH rH rH rH rH •d a a >. rH O O H a M M th c CN ON o MH Mm 00 o CM 00 m CO CO rH d o • 1 • 1 t • 1 • 1 \ • 1 "•

4J

u CO o fH

m CO § « CO iH »H •d o o >. O d “d -d rH rH o <d <a -I CO rH a a u >

\D 00

O 00 rH fH CM lO NO a o o -H •H o B^ ^ CNJ v£) o CO vT CM CM CM m •H rH O H U

CJ rH CM Q* o

CO CO CO CO CO in • • o lU • 00 NO O. CO O CO 4J d 1 1 1 u

00

0) a o o CM 00 CM rH CM CO

M * a •H m o m vO vO 00 O CM in 00 lU d

•H a • • d

dd >xi a H O iH o o o o .-1 vO CN vo 0 0 0 4)

•iH «H «H >M 4J

iJ MJ 4J o

(d Cd <d • MJ u u 0 o o

4J

CO 1 CM CO1 Mf1 m1 .3.3.3d

u

a.

<u CO CO CO CM CO CO ^ cn rH CO NO

«

«

H U< C'J u. CM CO pLi

m IX, Cti vf *

41
c

O 1H

•H Q)

4J •X3

CO O

3 6

'a f

0)e •!) O 4J

CO e

s

U-l o

o y

CO TJ a c

o (d

y

0Ou

y a

^ c a

u o a

E c

y a B § a

X ^

y

y H C ^ o

0

o y H y ^ 4J 3 H 9 ^

C

00 vo r^ O'

«4* o cn ^ O

<4’ cA m (A m

so CM *4 »4 *H

fH m fH m

cn <0 CA CM CM

S88SS

V V V V O O O

o

C I ©oCM CM I O_____ CM CM CM CM | CMCMCMCMCMCSCMCMCMCMCM __ _____

VVVVVVVVVVV

ooomooooooomiAOOooomiAiAO OO«0 VCMO^^«4'CMCMV V V “

I—I '£ sO

ooooOi-MiHcMmoooiHinooiHcMtnooo'fHino'

0 0

y y w t/i

y y y g g g 2 SS 2S

42

*

Refer

to

table

6

for

more

complete

description

of

coatings.

**

Gas

concentrations

estimated

with

calorimetric

Indicator

tubes.
NBS-114A (REV. S-78)

U.S. DEPT. OF COMM. BIBLIOGRAPHIC DATA

SHEET

1. PUBLICATION OR REPORT NO. NBSIR 78-1584 %aa;

4. TITLE AND SUBTITLE

SUBMARINE COMPARTMENT FIRE STUDY-FIRE PERFORMANCE EVALUATION OF

HULL INSULATION

5. Publication Date May 1979

7. AUTHOR(S) B. T. Lee and J. N. Breese

8. Performing Organ. Report No.

9. PERFORMING ORGANIZATION NAME AND ADDRESS

NATIONAL BUREAU OF STANDARDS

DEPARTMENT OF COMMERCE

WASHINGTON, DC 20234

tkitNo.

11. Contract/Grant No.

12. SPONSORING ORGANIZATION NAME AND COMPLETE ADDRESS (-Sfreer. city, state, ZIP)

Ship Damage Prevention and Control

Naval Sea Systems Command

Department of the Navy

Uashingt-f^n D . C . 20362

13, Type of Report & Period Covered Final Report

15. SUPPLEMENTARY NOTES

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

16. ABSTRACT (A 200^word or leas factual aummary of moat aignificant information. If document includea a significant bibliography or

literature survey, mention it here,) Certain foam rubber materials which are currently used to insulate the interior of

submarines are shown to possess a serious fire risk potential. Flame spread tests often

do not adequately reflect the fire hazard potential of these materials. It is shown

that compartment fire testing is the only satisfactory method of evaluating these kinds

of materials at the present time.

Fire barrier coatings for protecting these hull insulations are also investigated.

Two candidate coatings are found to prevent full fire involvement of an insulated com- partment following a moderately large flame exposure and at the same time meet the Nav>’’

elasticity requirement for submarine application. The study includes comparisons of

model and prototype compartment fire behavior and demonstrates the practicality of usini

quarter-scale fire tests for screening compartment finish materials.

17. KEY WORDS (six to twelve entrlee; alphebetical order; capitatixe only the llrat letter of the first key word unless a proper name; Comb^stion**pro^^^^ fire barrier coatings; fire growth; flame spread; foam insulation;

heat release; Interior finish; laboratory fire tests; material ignitability; submarine

compartment

18. AVAILABILITY Unlimited

I I For Official Distribution. Do Not Release to NTIS

I I Order From Sup. of Doc., U.S. Government Printing Office, Washington, DC

20402, SD Stock No. SN003-003- nn Order From National Technical Information Service (NTIS), Springfield, VA. 22161

19. SECURITY CLASS

(THIS REPORT)

UNCLASSIFIED

20. SECURITY CLASS

(THIS PAGE)

UNCLASSIFIED

21. NO. OF

PRINTED PAGES

49

22. Price $4.50

USCOMM-OC


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