Applications and Uncertainties Associated With Measurements Using FTIR Spectrometry

7/29/2019 Applications and Uncertainties Associated With Measurements Using FTIR Spectrometry

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http://irc.nrc-cnrc.gc.ca

Applications and Uncertainties

Associated with Measurements UsingFourier Transform Infrared Spectrometry,

Gas Chromatography-Mass Spectrometry

and Selective Ion Electrode Method in

Fire Suppression Tests

I RC - I R - 7 4 5

Liu, Z.G.; S u, J .Z.; Kim, A.K .; Kanabus-Kaminska, J .M.; Lusztyk, E .

J une 1997
http://irc.nrc-cnrc.gc.ca/http://irc.nrc-cnrc.gc.ca/


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ABSTRACT

During full-scale fire suppression tests conducted at the National Fire Laboratory

of the National Research Council Canada, Fourier Transform Infrared (FTIR)

Spectroscopy, Gas Chromatography-Mass Spectrometry (GC/MS) and Specific Ion

Electrode (SIE) method were employed to monitor the concentrations of the gaseoussuppression agents in the test compartment. Also, these methods were used to determine

the halogen acid gases generated during the fire suppression process. This report

describes the application of these three analytical methods for a series of tests conducted

with HCFC Blend A.. The results for the measurements of gaseous agent and halogen

acid gas concentrations using these three methods are provided. The uncertainties

associated with measurements using these three techniques are analyzed in detail.

It is shown that FTIR Spectroscopy provides an instantaneous and continuous

method for the measurement of multiple chemical species in the fire tests with reasonable

accuracy. The GC/MS and the SIE methods involve periodical sampling and off-line

measurements. Uncertainties associated with measurements using these analyticaltechniques are strongly dependent on the characteristics of the analytical methods

themselves, the set-up of the sampling system, calibration procedure, sampling procedure,

quantitative analysis and testing conditions. Considerable care is required to obtain

accurate measurements in the presence of halogen acid gases.


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TABLE OF CONTENTS

ABSTRACT I

TABLE OF CONTENTS II

NOMENCLATURE IV

1.0 INTRODUCTION 1

2.0 TEST FACILITIES AND PROCEDURES 2

2.1 Fire Suppression Agents 2

2.2 Test Room 2

2.3 Fire Scenarios 2

2.4 Experimental Set-Up 2

2.5 Test Instruments 3

2.5.1 Fourier Transform Infrared (FTIR) Spectroscopy 3

2.5.1.1 Calibration of the FTIR Spectroscopy 3

2.5.1.2 Sampling and Analyzing Procedure of FTIR Spectroscopy 4

2.5.2 Gas Chromatography-Mass Spectrometry (GC/MS) 42.5.2.1 Calibration of GC/MS 4

2.5.2.2 Sampling and Analyzing Procedure of GC/MS 4

2.5.3 Selective Ion Electrode (SIE) System 5

2.5.3.1 Calibration of SIE 5

2.5.3.2 Sampling and Analyzing Procedure of SIE 5

2.6 Test Procedure 6

3.0 TEST RESULTS 7

4.0 UNCERTAINTIES ANALYSIS 9

4.1 Uncertainties in the FTIR Spectroscopy 9

4.2 Uncertainties in GC/MS 10

4.3 Uncertainties in SIE System 115.0 SUMMARY 13

REFERENCES 14

Appendix 1: HCFC Blend A Concentrations Measured by GC/MS

Appendix 2: F-

and Cl-

anion Concentrations Measured by SIE System


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NOMENCLATURE

FTIR Fourier Transform Infrared

GC/MS Gas Chromatography-Mass Spectrometry

HAPE Halon Alternative Performance Evaluation

HCFC hydrochlorofluorocarbon

HCl hydrogen chlorideHF hydrogen fluoride

TDP thermal decomposition products

SIE Selective Ion Electrode


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1. INTRODUCTION

Increasing concerns about the environmental consequences of the utilization of

chemical fire suppression agents have recently prompted worldwide efforts to develop and

evaluate environmentally-friendly replacements for Halon 1301 and Halon 1211 [1 - 5].

An ideal halon replacement for total flooding applications should meet these importantcriteria: high fire suppression effectiveness, low direct and by-product toxicity, zero ozone

depletion and short atmospheric lifetime. Various analytical techniques are being used to

evaluate whether halon replacements meet such criteria or not [6].

In full-scale fire tests for the Halon Alternatives Performance Evaluation (HAPE)

project conducted at the National Fire Laboratory, the National Research Council Canada,

Fourier Transform Infrared (FTIR) Spectroscopy, Gas Chromatography-Mass

Spectrometry (GC/MS) and Selective Ion Electrode (SIE) method were used to monitor

the concentrations of the agents used for fire suppression and to determine the combustion

by-products generated during fire suppression [7]. Good results were obtained using

these analytical methods. However, the test results indicated that there were someuncertainties associated with the measurements obtained using these test methods.

Although these methods are often used in fire tests, no literature is available that discusses

in detail the uncertainties associated with measurements obtained using these analytical

methods.

Previous research [8 - 11] reported that some difficulties exist when measuring

combustion by-products in fire suppression tests, because of the severe testing conditions

and probable contamination and/or loss of samples during the measurements. Dierdorf et

al. [12] discussed the advantages and disadvantages of three measuring modes using a

FTIR to determine combustion by-products in fire suppression test. Bulien [13] described

the application of a FTIR spectrometer for measuring toxic smoke components in fire test.He indicated that missing information and details in calibration routines could lead to

differences in results obtained using a FTIR spectrometer.

This work describes the application of the FTIR, GC/MS and SIE methods in full-

scale fire tests. The results of the measurements of the agent and the halogen acid gas

concentrations using these three methods in Phase I of the HAPE project are compared.

The uncertainties associated with measurements using these techniques are then analyzed

in detail. The FTIR Spectroscopy provides an instantaneous and continuous method for

the measurement of multiple chemical species during the fire tests. The GC/MS and the

SIE methods involve periodic sampling and off-line measurements. Uncertainties related

to measurements obtained using these techniques are strongly dependent on the

characteristics of the methods themselves, the set-up of the sampling system, calibration,

sampling procedure, quantitative analysis and testing conditions.


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2.0 TEST FACILITIES AND PROCEDURE

2.1 Fire Suppression Agents

In Phase 1 of the HAPE project, HCFC Blend A was evaluated as a potential

replacement for Halon-1301 [7]. HCFC Blend A is a mixture of halogenated

hydrocarbons with 82% HCFC-22 (CHClF2), 9.5% HCFC-124 (C2HClF2), and 4.75%HCFC-123 (C2HCl2F3). The remaining 3.75% is a de-toxifying agent, lemonene, that

gives the agent its characteristic odour. The design agent concentration for fire

extinguishment and thermal decomposition products (mainly HF and HCl) generated

during fire suppression were examined in full-scale fire tests. As shown in Table 1, the

thirteen tests conducted in Phase 1 of the HAPE project involved a wide range of agent

concentrations (8.6 - 14.7%), nozzle design, discharge manifold and fire scenarios.

2.2 Test Room

A 121 m3

compartment, similar to Radar Room No.2 on the Navys Halifax Class

frigates, was constructed inside the Burn Hall of the National Fire Laboratory. The testroom is shown in Figure 1. It has a steel access door, three viewing windows and a

pressure relief vent near the floor of the South wall.

2.3 Fire Scenarios

Test fires in Phase 1 of the HAPE project included eight tell-tale (TT) fires, three

50 kW square-pan (SP) fires and one 400 kW round-pan (RP) fire. The fire scenarios

used for tests are given in Table 1. Heptane was used as the fuel for the tell-tale, square-

pan and round-pan fires. Their locations in the compartment are indicated in Figure 1.

2.4 Experimental Set-Up

The mass loss rate of the agent as it discharged from the cylinder was measured by

a weight scale with a digital readout. Thermocouples were placed at each fire location to

determine the extinguishing time. Three thermocouple trees were set up in different

locations of the compartment to measure room temperatures (see Figure 1).

Three quartz ports connected to stainless steel sampling lines were placed at the

same locations as the thermocouple trees. The sampling ports were arranged at different

elevations to measure the distribution of the agent in the compartment. The elevation of

these ports is indicated in Figure 1.

As shown in Figure 2, the sample gases in the compartment were sampled

continuously using three sampling quartz ports. The samples were filtered with microfiber

filters in the sampling lines. A switching system, using solenoid valves, connected the

FTIR to the gas-sampling lines from each of the three locations at 30 second intervals.


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The sampling port for the collection of samples for measurement using GC/MS

was located after the FTIR cell. These samples were used to determine the concentration

of volatile organic compositions.

Secondary, samples were obtained for analysis using SIE method. These samples

were obtained using a 6 meter length of sampling line connected to the GC/MS samplingport (see Figure 2). The SIE method was used to determine acid gas concentration.

All the sampling lines from the sampling ports in the room to the gas cell of the

FTIR and the sampling port of the GC/MS were heated and maintained at the temperature

of 155oC. This prevented the condensation of sample gases in the sampling line. The

sampling line from the GC/MS sampling port to the SIE sampling port was not heated.

All sampling lines were pumped continuously prior to the test and after the test to ensure

clean gas samples.

2.5 Test Instruments

2.5.1 Fourier Transform Infrared (FTIR) Spectroscopy

The FTIR spectroscopic method is based on the combination of an interferometer,

usually of the Michelson type, with a sensitive infrared detector and a computer [14 - 17].

FTIR spectroscopy provides sensitive and very fast measurements with high resolution

over a wide frequency range for the identification of a broad range of chemical

compounds. In the HAPE project, a BioRad FTS 175 FTIR spectrometer was used on-

line to measure the concentrations of the agent and its thermal decomposition products

during full-scale fire tests.

2.5.1.1 Calibration of the FTIR Spectroscopy

The calibration of the FTIR spectrometer for the agent, HCFC Blend A, was

carried out by using commercial calibration gases for the three major components of the

agent. The concentrations of HCFC-22, HCFC-123 and HCFC-124 used in the

calibration mixture were 7.50%, 0.49% and 0.4%, respectively, which was the same as

used in HCFC Blend A. Each HCFC component has a characteristic infrared absorption

peaks. For HCFC-22, three infrared absorption peaks centered at frequencies of 3,025,

2,213 and 596 cm-1

, were selected as the reference. For components HCFC-123 and

HCFC-124, the peaks centered at the frequencies of 697 and 672 cm-1

were used as

references, respectively.

Commercial HF samples, with concentrations of 970, 5339, 11,400 and 75,000

ppm, were used for calibration. HF has a unique absorption band in the frequency region

of 3,600 to 4,300 cm-1

with approximately 10 to 18 sharp absorption peaks. The eight HF

peaks at 3,788.9, 3,878.4, 3,921.0, 4,001.7, 4,039.7, 4,076.0 and 4,110.7 cm-1

were

selected as references for HF. During each fire test, the HF concentration at a given time

was determined by averaging the values corresponding to the eight peaks.


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The calibration of the FTIR spectrometer for HCl was carried out using 500 and

75,000 ppm commercial samples. More than 16 HCl absorption peaks were found in its

characteristic frequency region of 2,600 to 3,100 cm-1

. The peaks in the P-branch at

2,776, 2,799, 2,822 and 2,844 cm-1

were selected as the HCl references. In each fire test,

the HCl concentration at a given time was determined by averaging the values

corresponding to the four peaks.

2.5.1.2 Sampling and Analyzing Procedures of FTIR Spectroscopy

As shown in Figure 2, gas samples were drawn continuously from the

compartment through three gas-sampling lines to the FTIR spectrometer. The gas sample

from each sampling location was analyzed for 30 second using switching valve system.

An infrared (FTIR) spectrum over a wide frequency range of 400 to 4,500 cm-1

was

collected from the sample gas. Measurement using the FTIR lasted more than 12 minutes

for each test.

Quantitative analysis of the agent and thermal decomposition products wereobtained by comparing infrared absorption peaks from the fire tests with the

corresponding reference peaks obtained using the calibration gases.

2.5.2 Gas Chromatography-Mass Spectrometry (GC/MS)

Gas Chromatography-Mass Spectrometry (GC/MS) is the combination of the

chromatographic technique with mass spectrometry: full use is made of the separating

power of GC together with the structural information derivable from MS [18 - 20]. In the

HAPE project, a Model 5995 Hewlett/Packard Gas Chromatography/Mass Spectrometer

was used to measure the concentration of the agents used and other components present

in the test room.

2.5.2.1 Calibration of GC/MS

Several commercial single component gases were used to calibrate the GC/MS.

The concentrations of HCFC-22, HCFC-123 and HCFC-124 components used for the

GC/MS calibration were the same as those used in the FTIR calibration (7.50%, 0.49%

and 0.4%, respectively). The single component standards were sampled using an air-tight

syringe from a decompressed free-flowing stream. Various volumes of calibration gases

were then loaded on the sorption tubes.

An Envirochem Model 810 A with two stage thermal desorber/concentrator was

used to thermally desorb and concentrate the volatile component prior to analysis in the

GC/MS. The volatile constituents were then separated in the capillary columns and

analyzed by the MS detector. The corresponding ion spectrum for each component was

compared with the NBS75 spectral library with the aid of a computer. Their peaks were

identified and quantified as MS counts. Volume normalized MS area for each component


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was then plotted against the tube load. A linear equation was fitted through the

experimental points for each component:

Ci = Ai + Bi X (1)

where Ci is the concentration of ith component [ppm], A i and Bi are response factors ofith component respectively and X is the normalized MS response [cts/mL].

2.5.2.2 Sampling and Analyzing Procedures of GC/MS

The GC/MS was not conducted on-line. The measurement using the GC/MS

involved: preparing sorption tubes, sampling, transporting and storing samples, and

analyzing samples in the laboratory.

In Phase 1 of the HAPE project, three types of sorption tube (Carbotrap and

Carbotrap tubes and Standard Three Layer Glass Beads-Teenax-Ambersorb tubes)

were used. Prior to the test, the sampling tubes were cleaned by purging with ultra purehelium for 10 to 15 minutes while they were heated to a temperature of 250

0C.

As shown in Figure 2, the sampling port for GC/MS was located after the FTIR

cell and consisted of a SS-Tee that was equipped with a teflonized septum under a Swage-

Lok Fitting. During the test, the gases from the test room were sampled manually with a

gas-tight high precision syringe (Hamilton 1 mL). The contents of the syringe were then

injected in a stream of laboratory air into a sorption tube. The tube was later stored in a

screw capped glass sheath. At the end of the test, the exposed sorption tubes were

transported to the GC/MS facility where they were thermally desorbed and analyzed.

The components of the sample gas were identified with the aid of a HP supplied

75,000 compound library with a probability matching algorithm and three other libraries

[21]. Quantitative analysis of the agent concentrations was obtained by using equation (1)

and comparing the peaks recorded from the fire tests with the corresponding reference

peaks produced using the calibration gases.

2.5.3 Selective Ion Electrode System

Thermal decomposition products, including hydrogen fluoride (HF) and hydrogen

chloride (HCl), were produced in the fire suppression process due to the interactions

between the agent and the flame. In Phase 1 of the HAPE project, the thermal

decomposition products were collected by Wet Chemistry and then analyzed using a

Selective Ion Electrodes (SIE) method.

2.5.3.1 Calibration of SIE System

Orion solid state Selective Ion Electrodes were used to determine the

concentrations of HF and HCl acid gases produced during the fire suppression process by


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analyzing the levels of F-

and Cl-

anions in a solution prepared using the gas samples [22,

23]. Each Selective Ion Electrode system was calibrated using calibration standards

prepared from 0.1 N Acculute solutions of NaCl and NaF using the Incremental

Technique method. A semi-logarithmic plot of each electrode potential versus halide ion

concentration was constructed. A calibration curve was fitted to more than 30 calibration

points to provide the appropriate response factor equation. For calibration, theconcentrations for F

-and Cl

-anions were varied from 0.0 to 8.0 and 0.0 to 40.0 mmol/L,

respectively.

2.5.3.2 Sampling and Analyzing Procedures of SIE System

As shown in Figure 2, the sampling port for Wet Chemistry using a SS-Tee was

located at the exit of the cold exhaust line. An all-glass threaded Supelco Midget bubbler

equipped with a gas frit diffuser to increase the gas/liquid contact surfaces. 22 mL screw-

cap vials were used as collection vessels. The collection vessels were prefilled with 10

mL of 0.1 N NaOH solution prepared using an Anachemia Acculute Standard Volumetric

Solution.

The gases were sampled through the vials at a volumetric flow rate of 100-200

mL/min for 90-120 seconds. The mass transfer between the gas stream and the solution

occurred in irreversible chemisorption-neutralization reactions. The gaseous hydrogen

fluoride (HF) and chloride (HCl) were then trapped from the sampling gases and dissolved

in the hydroxide solution while most other components in the sample remained

undissolved.

In the laboratory, the pH of the solution in each vial was adjusted with a small

volume of concentrated sulphuric acid. An aliquot of the exposed solution was thenadjusted using TISAB II solution. A Fluoride Selective Electrode was used to determine

the concentration of F-

anion. Another aliquot of the exposed solution was adjusted using

an ISA buffer and a Chloride Selective Electrode was used to determine the concentration

of Cl-

anion. The quantitative analysis of the F-

and Cl-

anions concentrations were

obtained by comparing the electrode potentials of the fire gases with the corresponding

calibration curves produced using the standard solutions.

2.6 Test Procedure

Computers controlling the data acquisition system and the FTIR were started

simultaneously at time zero. Test fires were allowed at least a 30 s pre-burn. During thepre-burn period, the door of the compartment was kept open. Agent discharge was

activated manually at 60 s and lasted about 10 s. The pressure relief vent and the access

door were deliberately held closed during the tests. The tests were terminated after 10

minutes. The pressure relief vent was then opened and a fan connected through an

exhaust duct was activated to ventilate the room.


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3.0 TEST RESULTS

The FTIR and GC/MS were used to measure the agent concentrations and the

FTIR and SIE were used to measure the acid gases generated during the fire suppression

process.

Agent Concentrations

As shown in Table 1, Test H-1 was a dump test, without any fire, to determine the

agent discharge time and its concentration in the room. Test H-12 was a fire test without

any extinguishing agent used. These two tests are not discussed in the present work. In

Tests H-2 to H-6, the door was opened for a moment to relieve some of the pressure

during the discharge. For all subsequent tests, both the louvers of the pressure relief vent

opening and the door were kept closed during the discharge.

The filters in the sample lines are designed to remove most of the particles from

the sampling gases. The filters must be changed prior to every test. However, the filters

in the sampling lines were not changed until Test H-7 in Phase 1 of the HAPE project. Asa result, the filters in the sampling lines were clogged during Tests H-2 to H-6. The

clogged filters affected the measuring accuracy of FTIR, GC/MS and SIE. After Test H-

7, the filters were changed prior to every test.

The agent concentrations measured by GC/MS in Phase 1 of the HAPE project are

listed in Appendix 1. The agent concentrations measured by FTIR are shown in Figure 3

(for Tests H-2, H-3 and H-7 to H-13). The agent concentrations measured by GC/MS in

the corresponding tests were plotted in Figure 4.

The FTIR spectroscopy method continuously records the changes of agent

concentrations in the compartment from the beginning of the discharge. The agentconcentration in the compartment quickly reached its design value and was distributed

uniformly in the compartment shortly after the discharge. The agent concentrations

measured by the FTIR from different sampling ports did not display any obvious

fluctuation.

For Test H-2, the target agent concentration in the room was 8.6%. The FTIR

results showed that the maximum agent concentration actually reached 9% at the

beginning of the test, then continuously dropped. For Test H-3, the agent concentrations

as measured by FTIR were lower than the design value (8.6%), because the filter in the

sampling lines was clogged during the test. After Test H-7, the agent leakage from the

room was minimized during the discharge by closing both the door and the louvers of the

pressure relief vent. The filters in the sample lines were also changed for every test. As a

result, the agent concentration in the compartment did not drop after the discharge and the

agent concentrations measured by the FTIR were very close to the target concentration.

The target concentration in Test H-7 was 9.3% and the average agent concentration

measured by the FTIR was 9.2%.


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The number of points measured by GC/MS method for in full scale fire tests was

limited. In Test H-8, only four GC/MS data points were obtained in a testing period of

nearly 400 seconds, in comparison with 180 data points obtained using the FTIR method.

Also with the switching system, the gases from some sampling lines were missed during

the sampling process for GC/MS.

The agent concentrations measured by GC/MS showed significant fluctuations

from one testing point to another, as shown in Figure 4. The measured values obtained

using the GC/MS method were lower than the target concentrations as well as the values

measured by FTIR. In Test H-11, the average agent concentration measured by GC/MS

for a testing period of nearly 400 seconds was 5.58% compared with the design

concentration of 8.6%.

Thermal Decomposition Products (TDP)

Thermal decomposition products generated during the fire tests are strongly

dependent on the size of the fire and the agent concentration used for suppression. The

HF and HCl concentrations measured by SIE in Phase 1 of the HAPE project are listed inAppendix 2. HF and HCl concentrations measured by FTIR and SIE methods are shown

in Figures 5, 6 and 7.

The FTIR spectroscopy continuously recorded the formation of halogen acid gases

in fire suppression from the beginning of the discharge. In Test H-2, eight tell-tale fires

were employed but not extinguished. The FTIR results show that only a small amount of

halogen acid gases were produced in the test with relatively small fires. With the increase

in the fire sizes (e.g. 200 kW in Tests H-3 and H-8), very high concentrations of halogen

acid gases were produced, when the fires were not extinguished. However, when the

agent concentration was increased to 14.7% in Test H-10, Figure 7 shows that only a

small amount of HF and HCl acid gases were produced as the fire was quicklyextinguished. When the fires were reignited at 680 s in Test H-10, after an agent

concentration had decreased due to the operation of the exhaust fan, a significant amount

of halogen acid gases were produced.

The FTIR data in Figures 5 and 6 shows that HF and HCl concentrations measured

in Test H-3 were lower than those measured in Test H-8 under the same fire scenarios.

This indicates that the clogged filters in Test H-3 resulted in an underestimation of the

production of halogen acid gases during the fire suppression process.

In some unextinguished tests (e.g. H-8, H-9 and H-13), HF concentrations

measured by FTIR displayed significant fluctuation from one sampling port to another,

although the agent was distributed uniformly in the test room. This is because the

formation of halogen acid gases varied depending on the local temperature. In Test H-8,

sampling port 3 was close to the ceiling of the room where the local gas temperature was

high. Sampling ports 1 and 2 were located at low elevations close to the floor, where the

local gas temperature was relatively low. Hence, halogen acid gases measured at sample

port 3 were higher than those measured at the other two ports.


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In comparison with the measurements using the FTIR, the acid gases measured by

the Wet Chemistry method were integrative samples from three sample points and

represented a time and space-averaging of the concentrations in the test room. The results

shown in Figure 6 for Tests H-8, H-9 and H-13 indicated that HF and HCl concentrations

measured by the Selective Ion Electrode System were much lower than those measured bythe FTIR spectroscopy. This suggests that some of the acid gases were lost in the

sampling systems.

In Test H-10, HF and HCl concentrations measured by the Selective Ion Electrode

System were much higher than the concentration measured by the FTIR and had almost

the same levels as measured in Tests H-9 and H-13 in which the fires were not

extinguished. This was not true for the case where the fire was quickly extinguished. In

this test, the sampling system for the Wet Chemistry method were probably contaminated

when the sample gases flowed through a long and cold stainless steel sampling line.

4.0 UNCERTAINTY ANALYSIS

Uncertainties generated from measuring agent concentrations and thermal

decomposition products are strongly dependent on the characteristics of the analytical

methods themselves, the set-up of the sampling system, calibration and sampling

procedures and testing conditions.

4.1 Uncertainties in FTIR Spectroscopy Measurement

The FTIR was used to continuously measure the components of the gases sampled

from the test room. The uncertainties related to the measurements with the FTIR are due

to the calibration, sampling and quantification of experimental signals of the FTIR.

Uncertainties in the Calibration of the FTIR

The uncertainties associated with the FTIR calibration can be attributed mainly to

the impurity and concentration range of the calibration gas, and calibrated data points

required to form a proper calibrating curve.

For the calibration of the agent, the concentration of the agent was about 8.5%

with a single-point calibration. This could cause some uncertainties in some tests as the

agent concentrations were higher than the calibrated concentration.

For the calibration of HF, commercial samples with four HF acid concentrations

were used to construct a proper calibration curve. For the calibration of HCl, however,

commercial samples with only two HCl acid concentrations were employed to produce a

calibration curve. During the full-scale fire tests, a large amount of acid gases were

produced in the unextinguished fires. The calibration ranges for the halogen acid gases

covered the concentrations of HF and HCl acid gases produced in the tests. However, the

increase in the acid gas concentration is not linearly [2]. As a result, the limited numbers


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of calibration points used for HCl could result in some uncertainties in the measurement of

acid gases.

Uncertainties in the Test of the FTIR

The measurement using FTIR spectroscopy in the HAPE project was the external

absorption mode. The gas samples were withdrawn through the metal sampling line andmeasured at the outside of the test room. The filters in the sample lines could result in

some uncertainties in the measurements as the filters were clogged in some tests. Also,

the particles retained by the filter, which were highly absorbent and reactive, could also

prevent a fraction of the halogen acid gases reaching the FTIR for analysis. As shown in

Figures 3 and 5, the concentrations of the agent and halogen acid gases measured by the

FTIR in Test H-3 were significantly lower than those without the clogged filters in the

later test.

Also, the acid gases are very reactive and, even though stainless steel sampling

lines were heated, the interaction between the reactive acid components and metal tubes

occurred, resulting in losses of sampling acid gases and increased the uncertainties in themeasurements.

Uncertainties in the Quantitative Analysis of the FTIR

Since multiple chemical compounds were produced in the fire tests, there were

overlaps of the FTIR signals in some analysis regions. The signal noise could lead to

ambiguous determination of the exact height and area of some absorption peaks for the

analysis of the agent and acid gases. Hence, this could result in an underestimated or

overestimated concentrations of the agent and halogen acid gases.

It was estimated that for the cold discharge test, the uncertainties of the FTIR in

measuring the agent concentration was less than 7%. For the fire tests, the uncertaintieswere within 13%, because of the increasing uncertainties due to interference from the

decomposition products. The uncertainties of the FTIR in the measurement of HF and

HCl concentrations were estimated about 20% higher than those for the measurement of

the agent concentration [7].

4.2 Uncertainties in GC/MS Measurement

The GC/MS analysis for the measurement of the agent concentrations was

conducted off-line. The gases from the test room were sampled manually, put in storage,

transported to the laboratory and then analyzed by GC/MS. Thus, the uncertainties

produced in the measurement by GC/MS include not only those in the FTIR analysis, such

as calibration and signal quantification uncertainty, but also those uncertainties related to

the collection of the sample gas, and the storage and transport of the sample gas to the

laboratory.

Uncertainties in the Calibration of GC/MS


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As the same as discussed in the calibration of FTIR, the uncertainties related to the

calibration of GC/MS were due to impurities of the calibration chemicals, to the

calibration concentration and to the number of calibrated data points. The purity of

chemicals used for calibration was usually very high (99%). The number of data points for

the GC/MS calibration was also increased by diluting the calibration standards. However,

the concentration of the calibration standard was still lower than some values used in thetests. This could result in some uncertainties in determining the agent concentration, when

the agent concentration exceeded the calibrated range.

Uncertainties in the Sampling Procedure of GC/MS

There were two uncertainties arising from the sampling process for GC/MS

analysis. The first uncertainty resulted from the sampling period as the sampling gas was

quickly and manually drawn with a gas-tight syringe at the sample port. The second

uncertainty in the GC/MS sampling process was associated with the retaining capabilities

of the sorption tube.

The gas samples were affected by the clogged filters, the non-uniform pumpingcycles, the switch from one sample port to the other, and the fluctuation of the gas

composition in the compartment during the short manual sampling period. The sampling

volume of the gas-tight syringe also influences the sampling accuracy. In Test 6, the size

of the gas-tight syringe was changed from 1 mL to 0.5 mL. As shown in Appendix 1, the

agent concentrations measured by GC/MS in Test H-6 were significantly lower than those

measured in the test in which samples were obtained using a 1 mL syringe.

In Phase 1 of the HAPE project, three types of sorption tubes (Carbotrap ,

Carbotrap and the Standard Three Layer Glass Beads-Teenax-Ambersorb tubes) were

used. As shown in Figure 8, the concentrations of HCFC-123 and HCFC-124

components in the agent measured by GC/MS did not fluctuate with the changes in

sorption tubes used. But, the concentration of the HCFC-22 components changed from

one sampling point to another. The test results also showed that the retaining capabilities

of the Standard Glass Beads-Teenax-Ambersorb tubes was better than those of the other

two types of sorption tube, but still resulted in an underestimation of the concentrations of

HCFC Blend A in the tests.

The retaining capabilities of sorption tubes were also affected by their age and the

frequency of their utilization. Those sorption tubes with high utilization frequencies had

lower retaining capabilities due to the deactivation of the sorption sites. In Phase 1 of the

HAPE project, the age and utilization frequency of the sorption tubes were not identified.

This lead to differences in the retaining capabilities of sorption tubes for samples, because

different sorption tubes were used. The existence of halogen acid components in the

sample gases can further reduce the retaining capabilities of the sorption tubes by

damaging the beads of the sorption material.

Uncertainties in Storage and Transport for GC/MS Analysis


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12

The components of the agent HCFC Blend A are relatively stable. However,

during storage and transport, the chemical interaction between the halogen acid

components in the sample gases and the sorption material could damage the beads in the

sorption tubes. This resulted in some uncertainties for the GC/MS analysis.

Uncertainties in the Quantitative Analysis of GC/MSThe uncertainties produced in the quantitative analysis using the GC/MS method

are relatively small in comparison with those observed for the FTIR method. During

quantitative analysis of the sample gases, the interference from other chemical compounds

could be reduced to a low level by the proper separation of Gas Chromatography.

Hence, the uncertainties in the measurements obtained using GC/MS are mainly

due to the manual sampling procedure and the retaining capabilities of the sorption tubes.

The existence of the halogen acid components in the sampling gases further increases the

uncertainties in the GC/MS measurement. As a result, the agent concentrations measured

by GC/MS are significantly lower than the target concentrations. The uncertainties related

to the measurements with GC/MS are higher than those related to the measurements usingFTIR spectroscopy.

4.3 Uncertainties in SIE Measurement

The Selective Ion Electrode (SIE) method for the measurement of halogen acid

gases was also performed off-line. The sample gases were collected using Wet Chemistry

and then analyzed by the Selective Ion Electrode System. The uncertainties associated

with this analysis procedure include uncertainties in the collection and storage of the

samples using the Wet Chemistry method, and uncertainties in the calibration and

quantitative analysis of acid gases using the Selective Ion Electrode method.

Uncertainties in the Collection and Storage of Sampling Gases Using Wet Chemistry

For the HAPE project, heated stainless steel was used for the primary sampling

lines. However, the sample line that connected the GC/MS sample port to the SIE sample

port was not heated. Hence, the water vapour in the sampling gases could condense in the

tube, and halogen acid components in the sampling gases could react with the metal tube

in the presence of air and moisture during the test.

The acid gases are very reactive with the stainless steel [24]. Sheinson et al. [8, 9]

found that HF sampled using a short stainless steel tube showed significantly lower

concentrations than when sampled using a Teflon tube. As shown in Figure 6, the results

in the present tests also indicated that the concentrations of HF and HCl acid gases

measured by SIE were significantly lower than those measured using the FTIR, indicating

loses in the sampling procedure due to the interaction of the sample gases with the cold

metal walls. Also, cold metal sample lines can contaminate samples if the same sampling

system was repeatedly used in different tests. As shown in Figure 7, HF and HCl

concentrations measured by Selective Ion Electrode System in Test H-10 were much

higher than those values measured by FTIR, when the fire was quickly extinguished.


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The effectiveness of the sampling procedure for the Wet Chemistry method was

also affected by the collective efficiency of the bubbler vials and the flow rate of the

sampling gases through the bubbler vials. The collective efficiency of bubbler vials was

designed for a certain range of hydrogen halides concentrations. In the full-scale tests, a

large amount of halogen acid gases was produced, when the fire was not extinguished bythe suppression agent. The high concentrations of hydrogen halides produced during the

fire suppression process in some cases exceeded the upper range for the vial and lead to

premature saturation of the ion trapping solutions in the bubbler vial. Hence, halogen acid

components in the sampling gases were not all collected by Wet Chemistry in some tests.

The high volumetric flow rate of the sampling gases could also reduce the stripping of acid

components from the gas stream if the contact time for the gas bubbles within the solution

was too short.

Great care was also needed to store and transport the acid gases to prevent

unwanted reactions and loss, because of the reactivity of the acid gases.

Uncertainties in the Calibration and Quantitative Analysis Using SIE

For the calibration of the Selective Ion Electrode System, calibration standards

prepared from Acculute solutions were used. The calibration curves were plotted based

on more than 30 calibration points with a wide range of F-

and Cl-

anion concentrations.

The uncertainties related to the calibration of the SIE, therefore, are relatively small.

Other halogen components, such as COF2 and COFCl, were also produced during

the fire suppression process and hydrolyzed rapidly in the presence of water. Hence, in

quantitative analysis of the acid concentrations, F-

and Cl-

anions measured by Selective

Ion Electrode System include F

-

and Cl

-

anions from both halogen acid gases and othercomponents in the samples. As a result, the concentrations of the halogen acid

components in the samples could be overestimated by the SIE method. The FTIR results

showed that the amount of COF2 and other components generated during the fire

suppression process was relatively small. These results indicated a 5 - 10% uncertainty in

the HF and HCl measurement due to the presence of COF2 and other components in the

sample gases.

5.0 SUMMARY

Fourier Transform Infrared (FTIR) Spectroscopy can provide an instantaneous and

continuous method for the measurement of multiple chemical species in fire tests withreasonable accuracy. The uncertainties related to the measurements by FTIR are

influenced by the calibration concentrations, the number of calibrated data points, the

filters in the sampling lines and the signal interference in the quantitative analysis. The

chemical interaction between the sample gases and metal sampling lines could further

increase the FTIR uncertainties in the measurement of multiple chemical species.


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Gas Chromatography-Mass Spectrometry (GC/MS) for the measurement of the

agent concentration was conducted off-line. GC/MS cannot continuously record the

changes in the agent concentrations in the test room. The number of measuring points is

limited. The GC/MS method requires more elaborate calibration, and more time-

consuming and labour-intensive sampling procedure and quantitative analysis. For the

GC/MS, the uncertainties produced from the calibration procedure and quantitativeanalysis are relatively small, in comparison with those in the FTIR method. However, the

sampling procedures used to obtain samples for GC/MS analysis has a significant effect on

the measuring accuracy. Also, the retaining capabilities of the sorption tubes have a

significant effect. The existence of the halogen acid components in the sample gases can

further increase the uncertainties of the measurements by GC/MS. The overall

uncertainties in the measurement of the agent concentration by GC/MS are higher than

those with the FTIR spectroscopy. For the GC/MS method, the collection efficiency for

the sample gases must be systematically verified prior to the test.

The Specific Ion Electrode (SIE) method for the measurement of halogen acid

gases was also conducted off-line in the tests. The concentrations obtained with the SIEmethod are time and space-averaged. The uncertainties for this method are mainly due to

chemical interactions between the acid gases and metal sampling lines. In addition, the

improper design of the bubbler vials and flow rates in the sampling process also increases

the uncertainties of the SIE measurement. The concentrations of F-

and Cl-

anions

measured by the Specific Ion Electrode method are the sum of both halogen acid gases

and other components (e.g. COF2) in sampling gases.

REFERENCES

1. Grant, C.C., From the Halons of Yesterday to the Challenges of Tomorrow,

Proceedings of Fire Safety -- Without Halon?, Zurich, Switzerland, September

7-9, 1994, pp. 7-39

2. Su, J.Z., Kim, A.K. and Mawhinney, J.R., Review of Total Flooding Gaseous

Agents, J. of Fire Protection Engineering, vol.8, No.2, pp.45-64, 1996

3. Tapscott, R.E., Summary of Current Agents, Presented at 1994 International

CFC and Halon Alternatives Conference, Washington, DC, U.S.A., 1994

4. Metchis, K., The Regulation of Halon and Halon Substitutes, Proceedings of

Halon Options Technical Working Conference, Albuquerque, NM, USA., 1994

pp. 7-30

5. Kim, A.K., Su, J.Z., Mawhinney, J.R. and Kanabus-Kaminska, M., Full-Scale Fire

Testing of HFC-227ea and HCFC Blend A, Proceedings of Halon OptionsTechnical Working Conference, Albuquerque, NM, USA., 1996

6. Miller, T.L. and Green, A.E.S., A Survey of Techniques for Fire Suppressant

Studies, Proceedings: Halon Alternatives Technical Working Conference 1994,

PP.453-463.

7. Mawhinney, J.R., Kim, A.K., Su., J.Z., Kanabus-Kaminska, M., Crampton, G.,

and Lusztyk, E., Report on Full-Scale Fire Testing of HCFC Blend A - ND

Research Project HAPE 7665-1 (CFFM3-2), Client Report of National Fire


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15

Laboratory of the National Research Council Canada, 1995

8. Sheinson, R.S., Musick, J.K., and Carhart, H.W., HF and Hbr Production from

Full-Scale CF3Br (Halon 1301) Fire Suppression Tests, J. of Fire and

Flammability, Vol.12, P.229, 1981

9. Sheinson, R.S. and Alexander, J.I., HF and Hbr from Halon 1301 Extinguished

Pan Fires, Fall Meeting, Eastern States Section Meeting/the Combustion Institute,Pittsburgh PA, 1982

10. Di Nenno, P.J., Forssell, E.W., Peatross, M.J., Wong, J.T., and Maynard, M.,

Evaluation of Alternative Agents for Halon 1301 in Total Flooding Fire

Suppression Systems: Thermal Decomposition Product Testing, Proceeding:

Halon Alternatives Technical Working Conference, Albuquerque, P. 162, 1993

11. Linteris, G.T., King, M.D., Liu, A., Womeldorf, C. and Hsin, Y.E., Acid Gas

Production in Inhibited Diffusion Flames, Proceeding: Halon Alternatives

Technical Working Conference, Albuquerque, P. 177, 1994

12. Dierdorf, D.S., Moore, T.A. and Skaggs, S.R., Decomposition Product Analysis

During Intermediate-Scale (645 FT3) and Laboratory Scale (6.18 FT3) Testing of

NFPA 2001 Agents, Proceeding: Halon Alternatives Technical WorkingConference, Albuquerque, P. 177, 1993

13. Bulien, O. K., FTIR Spectrometer for Measuring Toxic Smoke Components in

Fire Testing - Review of Equipment and Calibration Routines in NT FIRE 047,

Fire and Materials, Vol. 20, PP.225-333, 1996

14. Smyth, M.R., Chemical Analysis in Complex Matrices, Ellis Horwood and

Prentice Hall, England, 1992

15. Zyka, J., Instrumentation in Analytical Chemistry, Ellis Horwood and Prentice

Hall, England, 1994

16. Ferraro, J.R. and Baslle, L.J., Fourier Transform Infrared Spectroscopy -

Techniques Using Fourier Transform Infrared, Vol. 3, Academic Press, New

York, 198417. Ferraro, J.R. and Baslle, L.J., Fourier Transform Infrared Spectroscopy -

Applications to Chemical Systems, Vol. 1, Academic Press, New York,

1984

18. Pecsok, R.L. and Shields, L.D., Modern Methods of Chemical Analysis John

Wiley & Sons, Inc., New York, 1968

19. Middleditch, B. S., Practical Mass Spectrometry, Plenum Press, New York,

1979

20. Ravindranath, B., Principles and Practice of Chromatography, Fllis Horwood

Limited, New York, 1989

21. Bruno, T.J., Spectroscopic Library for Alternative Refrigeram Analysis, NIST

Special Publication:794, 1991

22. Freiser, H., Ion-Selective Electrodes in Analytical Chemistry, Plenum Press,

New York, 1978

23. Kenkel J., Analytical Chemistry for Technicians, Lewis Publishers, Inc.,

Michigan, 1989

24. Lodge, J.P., Methods of Air Sampling and Analysis, 3rd edition, Lewis Publi.

Inc., Michigan, 1991


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25. LaQue, F.L. and Copson, H.R., Corrosion Resistance of Metals and Alloys, 2nd

Ed., American Chemical Society Monograph No. 158, New York, 1963


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Appendix 1: HCFC Blend A Concentrations Measured by GC/MS

HAPE 2-13March-April 1995

SAMPLE TIME of F22 F124 F123 AGENTSampling % % % as sum %min

HAPE 2, 17-Feb-95 8.6%NAFS IIIT2-1 0.5 0.00 0.00 0.00 0.00T2-2 2 2.48 0.18 0.23 2.88T2-3 3.5 2.36 0.18 0.24 2.79T2-5 6.5 2.04 0.20 0.29 2.52T2-6 8 3.10 0.21 0.31 3.62T2-7 9.5 2.82 0.21 0.30 3.33T2-8 11 2.34 0.19 0.28 2.82T2-10 15.5 2.70 0.18 0.26 3.13

T2-11 18.5 2.04 0.15 0.23 2.42T2-12 21.5 1.33 0.11 0.18 1.63

HAPE 3, 22-Feb-95 8.6%NAFS IIIT3-1 0.5 0.00 0.00 0.00 0.00T3-2 1 2.44 0.16 0.24 2.85T3-3 2 2.91 0.18 0.24 3.33T3-5 5 2.63 0.16 0.23 3.02T3-6 6.5 2.09 0.15 0.22 2.45T3-8 12.5 2.19 0.14 0.21 2.54T3-9 14 1.02 0.11 0.16 1.29T3-10 17 0.58 0.08 0.12 0.79T3-11 23 0.00 0.06 0.08 0.13

HAPE 4, 24-Feb-95 9.3%NAFS IIIT4-1 0 0.00 0.05 0.00 0.05T4-2 0.5 0.26 0.05 0.00 0.31T4-3 1 2.91 0.15 0.21 3.27T4-4 2 2.22 0.12 0.18 2.52T4-5 3.5 2.80 0.14 0.19 3.13T4-6 5 2.90 0.14 0.18 3.23T4-8 8 2.77 0.13 0.20 3.09T4-9 9.5 2.14 0.11 0.18 2.43T4-10 11 2.21 0.11 0.16 2.49T4-11 14 1.20 0.08 0.13 1.41T4-12 20 0.63 0.05 0.00 0.69

HAPE 5, 28-Feb-95 9.3%NAFS IIIT5-1 0 0.00 0.00 0.00 0.00T5-2 0.5 0.06 0.00 0.02 0.08T5-3 1 3.79 0.36 0.24 4.39T5-4 2 2.18 0.19 0.17 2.54T5-5 3.5 3.84 0.27 0.19 4.30T5-6 5 4.79 0.32 0.20 5.31T5-7 8 3.06 0.30 0.19 3.56T5-8 11 4.03 0.29 0.20 4.52


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T5-9 12.5 2.28 0.17 0.12 2.57T5-11 20.5 0.43 0.01 0.00 0.44

HAPE 6, 02-Mar-95 9.3%NAFS IIIT6-1 0 -0.00 0.00 0.00 -0.00T6-2 0.5 -0.00 0.00 0.00 -0.00T6-3 1 0.49 0.06 0.06 0.61T6-4 2 1.04 0.05 0.04 1.13T6-5 3.5 1.77 0.09 0.08 1.94T6-6 5 1.69 0.08 0.06 1.83T6-7 6.5 1.34 0.10 0.08 1.53T6-8 9.5 1.38 0.08 0.06 1.52T6-9 12.5 0.79 0.07 0.05 0.91T6-10 15.5 0.59 0.03 0.02 0.65T6-11 20.5 0.34 0.02 0.00 0.36

HAPE 7, 07-Mar-95 9.3%NAFS IIIT7-1 0 -0.00 0.00 0.00 -0.00T7-2 0.5 -0.00 0.00 0.03 0.03T7-3 1 3.40 0.24 0.18 3.82

T7-4 2 4.72 0.47 0.41 5.59T7-5 3.5 3.68 0.40 0.34 4.42T7-6 5 4.52 0.43 0.31 5.26T7-7 6.5 4.29 0.43 0.32 5.04T7-8 9.5 7.52 0.56 0.38 8.46T7-9 12.5 3.92 0.34 0.24 4.50T7-10 18.5 1.79 0.08 0.08 1.96T7-11 24 0.40 0.02 0.03 0.45

HAPE 8, 09-Mar-95 9.3%NAFS IIIT8-1 0 n/dT8-2 0.5 n/dT8-3 1 n/d

T8-4 2 3.75 0.34 0.30 4.39T8-5 3.5 3.48 0.35 0.29 4.11T8-6 5 2.43 0.36 0.28 3.06T8-7 6.5 2.80 0.38 0.28 3.46T8-8 9.5 5.23 0.45 0.30 5.98T8-9 12.5 2.39 0.20 0.15 2.74T8-10 17 1.84 0.11 0.08 2.03

HAPE 9, 16-Mar-95 8.6%NAFS IIIT9-1 0 -0.00 0.00 0.01 0.01T9-2 0.5 -0.00 0.00 0.01 0.01T9-3 1 0.28 0.02 0.03 0.32T9-4 2 5.37 0.45 0.33 6.15

T9-5 3.5 4.60 0.44 0.32 5.36T9-6 5 3.07 0.43 0.34 3.84T9-7 8 5.03 0.49 0.37 5.88T9-8 11 5.76 0.49 0.42 6.68T9-9 12.5 8.46 0.50 0.37 9.34T9-10 15.5 1.53 0.12 0.10 1.76

HAPE 10, 21-Mar-95 2x8.6%NAFS IIIT10-1 0 -0.00 0.00 0.00 -0.00T10-2 0.5 -0.00 0.00 0.00 -0.00


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T10-3 1 -0.00 0.18 0.11 0.29T10-4 2 4.48 0.55 0.52 5.54T10-5 3.5 5.90 0.61 0.59 7.10T10-6 5 12.66 1.09 0.69 14.44T10-7 6.5 8.45 0.85 0.65 9.95T10-8 9.5 12.79 0.97 0.58 14.34T10-9 11 4.78 0.45 0.31 5.54T10-10 12.5 3.54 0.36 0.28 4.18T10-11 17 2.27 0.19 0.15 2.61T10-12 27.5 0.14 0.00 0.00 0.14

HAPE 11, 22-Mar-95 8.6%NAFS IIIT11-1 0T11-2 0.5 -0.00 0.00 0.00 -0.00T11-3 1 5.40 0.39 0.29 6.09T11-4 2.5 4.78 0.38 0.29 5.45T11-6 5.5 4.74 0.38 0.29 5.41T11-7 7 4.67 0.38 0.33 5.38T11-8 8.5 6.01 0.44 0.35 6.80T11-9 11.5 5.06 0.43 0.36 5.85

T11-10 13 4.64 0.28 0.25 5.17T11-11 17.5 1.22 0.05 0.08 1.35

HAPE 13, 24-Mar-95 10%NAFS IIIT13-1 0 -0.00 0.00 0.00 -0.00T13-2 0.5 -0.00 0.00 0.00 -0.00T13-3 1 4.38 0.27 0.22 4.86T13-4 2.5 5.32 0.46 0.34 6.13T13-5 4 4.11 0.34 0.27 4.73T13-6 5.3 4.58 0.37 0.29 5.24T13-7 8.5 6.65 0.40 0.33 7.39


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Appendix 2: F- and Cl- Concentration Measured by Ion Selective Electrode Method

HAPE 3 - 13

March - April

1995

Sample middle time Cl- conc in gas F- conc in gass ppm ppm

HAPE 3, 22-Feb-95 8.6%NAFS III0 0 0

3-01 30 28 263-02 95.5 2598 59783-03 172 1852 84253-04 242 3887 124293-07 525 16765 132503-08 705 14501 10955


4-01 120 2633 33974-02 285 19383 118214-03 375 23519 113794-04 465 21351 122794-05 573 20343 127554-07 1140 4780 5834


5-01 60 3942 74095-02 150 5619 127275-04 270 11058 132205-05 330 12181 137335-06 390 14781 137335-09 705 14508 106605-10 855 8310 43985-11 1095 4882 4076

HAPE 6, 02-Mar-95 9.3%NAFS III6-01 0 14 1166-02 60 1817 56166-03 180 4555 95666-04 300 9407 92096-05 420 11980 8535

6-06 540 14537 85356-07 660 11980 79096-08 900 8540 48246-09 1140 3754 2527

HAPE 7, 07-Mar-95 9.3%NAFS III

7-01 0 15 477-02 60 1394 3475


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7-03 180 1955 66357-04 300 5398 80257-05 420 9189 71607-06 540 11149 66357-07 840 9644 52817-08 1140 3022 2202


0 0 08-01 55 1058 40768-02 235 1615 48578-03 303 5516 91558-04 415 4513 72118-05 535 6032 74918-06 655 4300 66838-07 900 1732 28638-08 1140 387 1065


0 0 09-01 55 1307 42959-02 175 1511 85179-03 295 1665 81999-04 415 2225 85179-05 535 2120 75999-06 660 2141 69669-07 900 897 25919-08 1140 255 1258

HAPE 10, 21-Mar-95 2x8.6%NAFS III

0 0 010-01 55 1983 435110-02 175 2184 469510-03 297 2436 547910-04 474 2572 536010-05 535 2406 487710-06 660 627 262510-07 895 465 227910-08 1014 337 152810-09 1140 170


0 0 0

11-01 55 1457 348311-02 175 1684 390411-03 295 1388 571011-04 415 1855 835411-05 535 1388 717511-06 670 1769 631911-07 797.5 944 4189


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11-08 895 610 287911-09 1020 345 1737

HAPE 13, 24-Mar-95 10%NAFS III

0 0 0

13-01 65 1218 324213-02 182.5 2229 847013-04 415 2834 884813-05 535 3438 884813-06 655 2974 704213-07 782.5 1614 377913-08 912 854 231113-09 1095 422 1538


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Table 1 Sequence of Tests in Phase 1 of HAPE Project

Test Date

1995

Target Conc.

HCFC Blend A

(%)

Pipe System Nozzle/

Orifice

Diam.

Fire Comments

Details

H-1 Jan-27 8.6 Navy standard

65 mm manifold

Type A

8.8 mm

None

H-2 Feb-17 8.6 Navy standard

65 mm manifold

Type A

11.5 mm

8 TTs

(see Note)


65 mm manifold

Type A

11.5 mm

8 TTs

3 SPs

200 kW

SPs 50 mm

from each

wall


65 mm manifold

Type A

11.5 mm

8 TTs

1 RPs

450 kW

RP between

nozzles


65 mm manifold

Type A

11.5 mm

8 TTs

3 SPs

200 kW

SPs 50 mm

from each

wall

H-6 Mar-2 9.3 Navy standard65 mm manifold

Type B6 @ 8 mm

8 TTs3 SPs

200 kW

Gas samplinglines adjusted

vertically

H-7 Mar-7 9.3 Navy standard

65 mm manifold

Type B

6 @ 8 mm

8 TTs

3 SPs

200 kW

SPs 50 mm

from each

wall

H-8 Mar-9 9.3 Modified

Removed 65 mm

manifold

Type B

6 @ 8 mm

8 TTs

3 SPs

200 kW

SPs 50 mm

from each

wall

H-9 Mar-16 9.3 Modified

Removed 65 mm

manifold

Type B

6 @ 8 mm

8 TTs

2 SPs

1 RP in centre

550 kW

1 SP moved

out to 300 mm

from each

wall

H-10 Mar-21 2 @ 8.6

Target 15 with

controlled

venting

Replaced 65 mm

manifold

two cylinders

discharge

Type B

6 @ 8 mm

8 TTs

3 SPs

200 kW

SPs 50 mm

from each

wall

H-11 Mar-22 8.6

Post-discharge

ignition

Navy standard

65 mm manifold

Type B

6 @ 8 mm

3 SPs

150 kW

Pans in

corners

SPs 50 mm

from each

wall

H-12 Mar-23 No discharge N/A N/A 3 SPs

150 kW

Pans in

corners

Non-

suppression

test

H-13 Mar-24 10 Navy standard65 mm manifold

Type B6 @ 8 mm

8 TTs3 SPs

200 kW

SPs 50 mmfrom each

wall

Note: Total heat output from eight TTs is estimated to be 50 kW; three SPs, 150 kW; one RP, 400 kW


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Time (s)

60 90 120 150 180

VolumetricConcentration(%)

0

2

4

6

8

10

12

H-2

H-3

H-7

H-8

Figure 3a. HCFC Blend A concentration-time profiles measured by FTIR

Spectroscopy for Tests H-2, H-3, H-7 and H-8.


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Time (s)

60 90 120 150 180


0

2

4

6

8

10

12

14

16

H-9

H-10

H-11

H-13

Figure 3b. HCFC Blend A concentration-time profiles measured by FTIR

Spectroscopy for Tests H-9, H-10, H-11 and H-13.


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Time (S)

0 200 400 600 800 1000 1200 1400


0

2

4

6

8

10

12

H-2

H-3

H-7

H-8

Figure 4a. HCFC Blend A concentration-time profiles measured by GC/MS for

Tests H-2, H-3, H-7 and H-8.


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Time (S)

0 200 400 600 800 1000 1200 1400


0

2

4

6

8

10

12

14

16

H-9

H-10

H-11H-13

Figure 4b. HCFC Blend A concentration-time profiles measured by GC/MS for

Tests H-9, H-10, H-11 and H-13.


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Time (s)

0 60 120 180 240 300 360 420 480 540 600 660 720 780 840 900 960

VolumetricConcentration(ppm)

0

2000

4000

6000

8000

10000

12000

14000

16000

18000

H-2 (FTIR)

H-3 (FTIR)

H-3 (SIE)

Figure 5a. HF concentration-time profiles measured by FTIR and SIE for Tests

H-2 and H-3.


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Time (s)

0 60 120 180 240 300 360 420 480 540 600 660 720 780 840 900 960


0

2000

4000

6000

8000

10000

12000

14000

16000

18000

H-2 (FTIR)

H-3 (FTIR)

H-3 (SIE)

Figure 5b. HCI concentration-time profiles measured by FTIR and SIE for Tests

H-2 and H-3.


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Time (s)

60 120 180 240 300 360 420 480 540 600 660 720


0

5000

10000

15000

20000

25000

H-8 (FTIR)

H-9 (FTIR)

H-13 (FTIR)

H-8 (SIE)

H-9 (SIE)H-13 (SIE)

Figure 6b. HCI concentration-time profiles measured by FTIR and SIE for Tests

H-8, H-9 and H-13.


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Time (s)

60 120 180 240 300 360 420 480 540 600 660 720

H

FandHCIConcentration(ppm)

0

1000

2000

3000

4000

5000

6000

HF (FTIR)

HCl (FTIR)

HF (SIE)

HCI (SIE)

Figure 7. HF and HCI concentration-time profiles measured by FTIR and SIE

for Test H-10.


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Time (s)

0 200 400 600 800 1000 1200


0

1

2

3

4

5

6

HCFC-22

HCFC-124

HCFC-123

Figure 8. The components of HCFC Blend A-time profiles measured by GC/MS

for Tests H-8.

Applications and Uncertainties Associated With Measurements Using FTIR Spectrometry

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