TROPODEGRADABLE BROMOCARBON EXTINGUISHANTS 

-PROGRESS OVERVIEWJ. Douglas Mather 

The University of New Mexico 

Robert E. Tapscott 

GlobeTech, Inc. 

INTRODUCTION 

In work most recently sponsored by the DoD Next-Generation Fire Suppression Technology 

Program (NGP), research efforts at The University of New Mexico have been evaluating chemical agents as substitutes for Halons 1301 and 121 1. This effort has been focused entirely on a 

new class of compounds referred to as tropodegradable bromocarbons. Testing results to date are 

very favorable, and there is strong indication that, as a group, the tropodegradable bromocarbons 

may well yield acceptable replacements for both Halon 1301 and 121 I. Past research work on 

new total-flood and streaming agents has established the potential of tropodegradable bromocarbons as fire suppressants; however, flame extinguishment experiments were insufficient to 

relate performance (and, for some compounds) flammability to structure [ 1 through 51. NMERI’s 

recent NGP project was conceived in part to address the need for more laboratory-scale fire 

extinuishment information on tropodegradable compounds. Several tropodegradable candidate 

compounds have been identified from the alkene, ether, and amine families. Acquisition of 

promising compounds to date has been primarily from the alkene and amine families. 

This report summarizes the past years acquisition, extinguishment and toxicology studies on 

tropodegradable bromocarbon extinguishants. The inhalation toxicity studies were performed 

under financial support from the US Air Force (Tyndall AFB) [6], the Next-Generation Program 

(NIST) [I], and the Advanced Agent Working group (AAWG). The Ames toxicity study reported here was performed by the Advanced Agent Working Group [6]. The report also covers current efforts to identify acquire and test additional tropodegradable compounds as well as screening techniques developed for performing cup-burner testing of small quantities of compound. 

EARLY DEVELOPMENT EFFORTS 

Commercialized halon replacements such as perfluorocarbons (PFC, FC), hydrochlorofluorocarbons (HCFC), hydrofluorocarbons (HFC), hydrofluoropolyethers (HFPE), and iodofluorocarbons (CF31) do not contain bromine. With the exception of CSI, all current commercialized 

halon replacements have much higher air concentration requirements for cup-burner flame extinguishment. This is largely attributable to the absence of bromine in the structures of these 

chemicals. All current commercialized halon replacements, except Chi, are significantly less 

effective in many scenarios than halons and exhibit long atmospheric lifetimes and high global 

warming potentials. 

In recent years two approaches to reintroducing bromine into fire suppressants have been tested. 

The first approach is based on the use of blends of bromoalkanes with HFCs or HFPEs. This 

approach, when compared to the performance of neat HFC or HFPE, does result in enhanced 

cup-burner flame extinguishment performance and streaming performance. The blend technology is currently being evaluated for commercialization. The second approach taken to reintroducing bromine into the fire suppression agent takes advantage of compounds with intrinsically 

very low atmospheric lifetimes (on the order of days or weeks) to act as a carrier or base structure 

to which a bromine atom is added (Table I). Such compounds are said to be tropodegradable 

154 Halon Options Technical Working Conference 2-4 May XKX) 
because for all practical purposes they rapidly and completely degrade within the troposphere and 

never reach the stratosphere or the earth's ozone layer. When bromine is contained within the 

molecular structure of a short atmospheric lifetime compound, the resulting chemical is referred 

to a tropodegradable bromocarbon. The carrier compounds generally are only partially 

fluorinated and incorporate chemical features that are reactive with atmospheric -OH or O-, or 

that are inherently polar such as alcohols and therefore subject to atmospheric removal by the 

rainout process. CFJs inclusion as a tropodegradable compound arises from photolysis of the 

C-I bond as a result of exposure to sunlight. 

TABLE I. TROPODEGRADABLE CARRIERS AND BROMINATED DERIVATIVES. 

~~~ ~~ 

Tropodepradable Base Structure Troaoderrndable Brornocarbon Derivative 

CH+?HCF3 CHz=CBrCF3, CHBr=CHCF? 

CH?=CFCF? CHBr=CFCF? 

CHz=CFCFzH CHr=CHCFzBr, CHBr=CFCF>H 

CHF=CHCF? CFBr=CHCF3, CHF=CBrCF? 

Tropodegradable compound atmospheric lifetimes have in some cases been measured but 

generally are estimated based on data generated for functional groups such as sites of unsaturation, numbers of C-H bonds, and substitution patterns. Early estimates of atmospheric lifetime 

for alkenes, which were as low as a few days, have now been demonstrated to be accurate." 

Amines are estimated to have atmospheric lifetimes on the order of one or more months. Ethers 

are estimated to have atmospheric lifetimes of days to months. The brominated ether CHjOCF2 

CHFBr (commonly known as Rotluorane) has been reported to have an to have atmospheric 

lifetime of 14 days [7]. 

The reactions that cause atmospheric decomposition of' a molecule differ for alkenes, ethers, and 

amines. For alkenes reaction with hydroxyl free radicals or with tropospheric or ground level 

ozone are expected to target the double bond while ethers and amines would be subject to 

hydrogen abstraction reactions by the -OH radical. Photolysis of the C-I bond is the predominant 

reaction pathway for iodinated fluoroalkanes such as (CFjI). Direct physical removal of alcohols 

through rainout is not contingent on the reactivity of the compound. 

RESEARCH ON TROPODEGRADABLE FIRE SUPPRESSANTS AT NMERI 

Concerted efforts to advance the research on tropodegradable bromocarbons as replacements for 

Halons 121 1 and 1301 began several years ago and conlinue to the present. Halon 1301 replacement work involving the evaluation of tropodegradable bromocarbons has received the bulk of its 

past funding by the Next-Generation Program (NGP) and by the Advanced Agent Working 

Group (AAWG). Halon 121 I replacement work has been funded exclusively by the US Air 

Force (Tyndall AFB). Additional funders who have contributed to these compound selection, 

acquisition and testing projects include the US Army TACOM, US Navy, Federal Aviation 

Administration (FAA), and Environmental Protection Agency (EPA). 

~ ~ 

-x Vladiniir Orkin, personal communication, NIST (41612000). 
A research strategy was developed early in these projects to govern the selection of compounds 

for acquisition and identification of relevant testing. This strategy is based on information 

gathered or estimates made on the types of compounds under consideration as well as individual 

compounds. Information gathered included estimates of atmospheric lifetime and ozone 

depletion potential (ODP), global warming potential (GWP), various toxicity end points, physical 

properties (e.g., boiling point vapor pressure, density, etc), and estimates of cup-burner flame 

extinguishment for Halon 1301 replacement candidates and streaming agent performance for 

Halon 121 1 replacement candidates. 

All of these research programs addressed the problem of selecting appropriate toxicity end points 

and developing a ranking of their relative importance. This information became part of the basis 

for the preliminary screening prior to actual acquisition and or synthesis efforts. Table 2 presents 

an example of the selection criteria developed early in the Halon 121 1 replacement program. 

Functional upper limits on compound boiling point for total flood, and to a lesser degree streaming agent applications were estimated. In the case of total-flood agents vapor pressure under the 

conditions of usage are seen as a primary factor in the fire or explosion performance of an agent. 

Estimates of theoretical ambient vapor pressure as a function of boiling point and ambient 

temperature (based on Trouton's constant) are summarized in Table 3. From this chart it can be 

estimated that for a compound to achieve a 4% air concentration at -40 "C, it must have boiling 

point no greater than 3 1 "C. Where application conditions are -10 "C the permitted boiling point 

limit is higher at 70 "C. This estimate says nothing about the time required to establish the 

targeted air concentration. 

TABLE 2. HALON 12 1 I REPLACEMENT CANDIDATE CRITERIA. 

Criteria Value 

Boiling Point <-800C 

LC5o* (4-hr) 

Cup-bumer performance < 5.0% 

ODP <0.02 

GWP < 5,000 

Atmospheric Lifetime < 5 years 

Cardiac Sensitization (CS,,,,,) 

Cleanliness No solid residue 

Application density 

> 50,000 ppm (5.0%) 

> 2 times the FEC 

Similar to that of Halon 121 I in a 5 by 5-ft 

n-heptane pan fire test. 

*Lowest concentration causing death in 50% of an animal test population. 

156 Halon Options Technical Working Conference 2-4 May Zoo0 
TABLE 3. ESTIMATES OF MAXIMUM USEABLE BOILING POINTS 

Conc. Ambient Temperature, T 

CA -60 -50 -40 -30 -20 -10 0 IO 20 30 40 50 

I 33 47 61 76 YO 105 119 133 148 162 176 191 

2 19 33 46 60 74 87 101 115 128 142 156 169 

3 II 24 31 51 64 77 91 104 I I7 130 144 157 

45 18 31 44 57 70 83 96 IOY 122 135 148 

5 0 13 26 39 52 65 77 90 103 116 129 142 

10 -14 -1 II 23 35 41 59 72 84 96 1 ox I20 

15 -22 -10 2 14 25 31 49 61 73 X4 Y6 I ox 

20 -28 -16 -5 7 19 30 42 53 65 76 88 99 

Example: To achieve a 4 vol% concentration at -20 "C, the maxiniuni allowable boiling point 

is 57 "C. 

The pivotal criteria that evolved through extensive evaluations and eventually formed a basis for 

selection and evaluation of compounds as either Halon 1301 or 121 1 replacement candidates are 

summarized in Table 4. 

TABLE 4. SELECTION PARAMETERS. 

Parameter 

estimated or determined 

Halon 12 I 1 replacement candidate Halon 1301 replacement candidate 

Fire Suppression Perfonnance NMERI LSDE (Streaming test) Cup-Burner (NMERI) 

Environmental Atmospheric Lifetime, ODP, GWP Atmospheric Lifetime, ODP, GWP 

Toxicity Acute inhalation, Ames test 

(mutaFenisity), carcinogenicity, (mutagenicity), carcinogenicity, 

cardiac sensitization cardiac sensitization 

Acute inhalation, Ames test 

Physical Properties Boiling point, vapor pressure Boiling point, vapor pressure 

Based on an analysis of atmospheric reactivity various chemical families were selected. The 

chemical families expected to exhibit short(er) atmospheric lifetimes and therefore provide the 

basis for developing tropodegradable bromocarbon extinguishants are listed below. 

Brominated alkenes 

Brominated ethers 

Brominated alkyl amines 

Brominated alcohols 

Brominated aromatics 

Brominated carboxylates 

Halon Opiions Toclinical Working Conlerencc 2-4 May ZOMJ I 57 
Of these chemical families, the brominated alkenes, ethers, and amines were judged the most 

likely to meet desired boiling point restrictions, environmental, and toxicity goals. Of these three 

families, the bromofluoroalkenes were judged the most favorable. Toxicity requirements are 

generally viewed as presenting the most difficult hurdle in the development of a halon replacement. 

Extensive toxicity information for many candidate compounds and chemical families was gathered and evaluated early in the halon replacement program. Published toxicity data for the building 

block molecule 3,3,3-trifluoropropene, indicating an LCSO of 430,676 ppm, was particularly 

favorable and suggested the possibility of developing an acceptable brominated derivatives.* 

One such brominated derivative of 3,3,3-trifluoropropene is 2-Bromo-3,3,3-trifluoropropene 

(boiling point 34 "C). This compound in fact had been used in inhalation testing involving dogs 

where the test animals were reported to recover uneventfully from the exposure [5]. Unfortunately no concentration data was provided for this test. Toxicity data for the bromofluorobutene, 

4-bromo-3,3,4,4-tetrafluorobutenes indicated a 4-hour ALC in rats greater than 19,300 ppm. 

This compound has also been found not to be mutagenic in Ames bacterial assay or clastogenic 

in Chinese Hamster Ovary (CHO) cell assay. 

To date the list of bromofluoroalkenes acquired for which cup-burner flame extinguishment has 

been characterized is presented in Table 5. The data all indicate that regardless of compound 

structure, straight chain or branched, and propene, butene, or pentene derivative the flame 

extinguishment is generally below 4% with most of the tested compounds yielding cup-burner 

values comparable to Halons 1301 and 121 1. Only when the degree of fluorination falls to less 

than 50% of available positions (total of number of H's, fluorines and bromines) does the cupburner value rise significantly above 4%. 

Testing of the streaming performance of tropodegradable bromofluoroalkenes is very limited. 

Data from a laboratory scale streaming agent test apparatus have been acquired. Figure 1 shows 

the relative performance of several experimental compounds, commercial agents, and the tropodegradables 2-bromo-3,3,3-trifluoropropene and 4-bromo-3,3,4,4-tetrafluorobutene compared to 

Halon 121 1. The test evaluates agent application rates vs fire out times. As can be seen from the 

chart, the compound 2-bromo-3,3,3-trifluoropropenes fire suppression performance approximates 

that of Halon 1211. 

Acute inhalation toxicity testing was performed last year on a limited selection of tropodegradable compounds representing a range of molecular weights, boiling points, and structural features. The list of compounds represented both straight chain molecules as well as branched 

molecules, and to a limited extent, structural isomers such as 2-bromo-3,3,3-trifluoropropene and 

l-bromo-3,3,3-trifluoropropene were evaluated. The test exposure protocol called for a 30-min 

exposure of 10 rats (5 male and 5 female) to each individual chemical at an air concentration of 

5%. Following the exposure the animals were removed from the exposure apparatus. observed 

for 2 hours, then sacrificed for examination of tissues. This testing was part of a project being 

performed under US Air Force funding to develop a replacement for the streaming agent Halon 

121 1 [6]. The toxicity testing program received additional funding and support from the AAWG, 

US Army (TACOM), and US Navy. 

*Lawrence R. Grzyll, Mainstream Engineering Corporation, personal communication, April 1997. 

158 Halon Options Technical Working Conferencc 2-4 May Zoo0 
TABLE 5. BROMINATED TROPODEGRADABLE HALOCARBON CUP-BURNER VALUES. 

CCOD Compound, Fomiula Boiling Pt Cup-burner 

ID 

707 

872 

873 

903 

1116 

135X 

1359 

1360 

1391 

1413 

(6 (% j 

I -Bromo-3,3,3-trifluoropropene, CF,CH=CHBr 40 

3-Brorno-3,3-difluoropropene, CBrFZCH=CH? 

2-Bromo-3,3,3-trijluoropropene, CF,CBr=CH, 

4-Bromo-3,3,4,4-tetrufluorobutene, CF,BrCF,CH=CH, 

2-Bromo-3,3,4,4,4-pentufluorobutene, CF,CFICBr=CH, 

2-Bromo-? ,3,4,4,5,5,5-heptafli1oropentene, 

CFICFzCF:CBr=CHZ 

2-Bromo-3-trifluoromethyl-3.4,4,4-tetratluorobutene, 

CFICF(CF~)CB~=CHI 

2-Bromo-3-trifluoroniethoxy-3,4,4,4-tetratluorobutenc, 

CFKF(OCF3 jCBr=CHZ 

I -Bronio-2-trifluoroniethyl-3,3,3-trifluoropropene, 

(CF?):C=CHBr 

I -Bromo-4,4,4,3,3-pentafl uorobutene, CFKFzCH=CHBr 

42 

34 

54 

56 

7x 

78 

75 

63 

58 

- 

"Testing performed using premixed agentpair mixtures. 

3.5::: 

4.5 

2.6 

3.5 

3.8" 

3.7" 

3.3" 

3.8" 

2.6"' 

3.1 %? 

- 

H;ilon Oplionc Tcchnical Working Conlcrcncc 2-4 May 2000 159 
Some of the results of this exposure testing are presented below in Table 6. Shown are the 

mortality/survivability for each chemical used in the exposure program as well as lung tissue 

observations made following animal sacrifice. A surprising number of the test compounds 

produced no mortality or lung tissue damage. Those compounds having the least impact on the 

test animals also had the lowest boiling points. Selected exposure observations made during the 

acute inhalation toxicity test and the two hour post exposure observation period are listed below 

in Table 7. The observations presented are for three of the compounds selected for continued 

evaluation. 

TABLE 6. ACUTE INHALATION TOXICITY TESTING. 

CCOD ID Formula Number of Rat Deaths Lung Tissue Observations 

(at necropsy) 

873 CH2=CBrCF3 0 All rat tissues normal 

707 CHBr=CHCF, 0 All rat tissues normal 

872 CH2=CHCBrF2 7 Lungs were mottled 

903 CHz=CHCF2CBrFz 0 All rat tissues normal 

1116 CHz=CBrCFICF3 0 Lungs were mottled 

1360 CH2=CBr(OCF3)CFCF3 IO Lungs were mottled 

1358 CH2=CBrCFzCF2CF3 1 (post exposure) Lungs were mottled 

1359 CHz=CBrCFC(CF3) 2 10 Lungs had marked mottling 

Organ weight and weight ratios reflected the post exposure observations (Table 8). Compound 

1 1 16 is described as resulting in the following post-exposure effects “labored breathing continued to 20 min post-exposure. Respiration continued in this manner until sacrifice.” This observation is reflected in the average lung weights for animals exposed to Compound 11 16, which 

are more than twice those of the control group. Tissue weights for Compounds 873,707, and 

903 are statistically the same as those of the control group by comparison. 

Following these successful tests of acute inhalation toxicity, the AAWG performed testing of 

Ames mutagenicity on three of the more readily available compounds. The results of the testing, 

which was performed by DuPont, are presented in Table 9. All three compounds tested negative 

in this test indicating that they are not mutagenic. 

As presented in this review, tropodegradable bromofluoroalkenes have been demonstrated to be 

effective fire extinguishants in both streaming and total-flood applications. Cup-burner data 

indicate that for compounds where the degree of fluorination is equal to or greater than 50%, the 

extinguishment concentrations are as low as 2.6%. Boiling points for many of the compounds 

acquired range from 34 to 74 “C. Testing of the performance of these compounds in actual fire 

and explosion suppression tests at sub-ambient temperature conditions is needed to assess 

performance. Toxicity testing results are very promising and further testing is planned in the 

near future. Atmospheric Lifetimes data reported during the HOTWC 2000 meeting confirmed 

the short lifetime estimates of a few days for the tropodegradable bromofluoralkenes. 

160 Halon Options Technical Working Conference 2-4 May 2000 
Exposure Test 

TABLE 7. ACUTE INHALATION TOXICITY TESTNG EXPOSURE OBSERVATIONS. ~ 

- Group 

Controls: 

Compound 873: 

Compound 903: 

Compound I1 16: 

Observations 

Normal during 30 min exposure. Occasional movement in tubes. Good pink color 

of extremities with normal respiration. Upon being unloaded rats appeared normal 

and begin grooming themselves. 

Relaxed breathing began shortly after exposure. Little movement within tubes 

within first few minutes then none thereafter. Animals appeared to be anesthetized. 

After exposure animals were anesthetized for a few minutes then began moving 

about although with impaired motor activity. Back to normal after about IO min 

post-exposure, and normal throughout to sacrifice. 

At 12 min of exposure color was good, breathing relaxed, and there was no 

movement indicating the rat\ were anesthetized. Animals remained this way 

throughout exposure. 

After exposure rats remained anesthetized for 2-3 min then began waking. Rats 

were stumbling around by 5 mi11 post-exposure and were very wobbly. By 20 min 

post-exposure all rats appeared normal and continued normally until sacrifice. 

At 3 min into exposure respiration was irregular, and became labored with gasping 

by X niin. At 13 min respiration was slowed and animals appeared to be 

anesthetized. By 20 min F058 (animal number) was breathing very slowly, paws 

were pale purple indicating insufficient oxygenation. 

By 5 min post-exposure rats were waking and had labored breathing: labored 

breathing continued to 20 min post-exposure. Respii-ation continued in this manner 

until sacrifice. 

TABLE X. ACUTE INHALATION TOXICITY TESTING ORGAN WEIGHT OBSERVATIONS. 

Orean Control Conmound X73 Compound 707 Compound 903 Compound I I16 

Lungs 0.962 0.980 I .007 1.054 2.21 I 

Kidneys 1.527 I.509 I .605 1.608 1.747 

Spleen 0.506 0.544 0.573 0.545 0.5 I4 

Heart 0.65X 0.696 0.692 0.7 I6 0.7 I5 

Lungibody ratio 0.429 0.43x 0.442 0.452 0.943 

TABLE Y. AMES MUTAGENICITY TEST RESULTS 

CCOD ID Compound. Form u I a Arne\ Te\t Rewlt 

873 2-Bromo-3.3,3-trifluoropropene, CF?CBr=CH* Negative 

YO3 4-Bromo-3,3,4,4-tetrafluorobutene. 

CFzBrCFzCH=CHz 

1116 2-Bromo-3,3,4,4,4-pentafl uorobutene, 

CFKF?CBr=CH? 

Negative 

Negative 

Halon Option\ Tcchriical Working Conlcrcncc 2-4 May ?OOIJ 16 1 
Limited testing of tropodegradable amines has also been performed. Several of the bromofluoroamines acquired are listed in Table 10. Though the compounds acquired have excellent cupburner flame extinguishment performance, their boiling points may make them unsuitable for 

anything but streaming applications. Additional bromofluoroamines with lower boiling points 

are being sought for testing as Halon 1301 replacements. 

Polyfluoroamines and polyfluorobromoamines listed in Table 11 give hope that this chemical 

family may yet yield additional compounds with boiling points as low as 20 to 30 T. Based on 

testing of perfluorinated amines expectations are that the acute inhalation toxicity of bromofluoroamines may be low. 

TABLE 10. TROPODEGRADABLE BROMOFLUOROAMNES. 

CCOD ID** Compound, Formula Boiling pt "C Cup-burner (9%) 

1392 Bis(trifluoromethyl)-2-bromo- 1,2,2-trifluoroethyl 12 2.4" 

amine, N(CF3)z(CHFCFzBr) 

amine, N(CF3)z(CFzCFHBr) 

N(CFTMCH?CF7Br) 

1393 Bis(trifluoromethyl)-2-bromo-1,1,2-trifluoroethyl 12 

1398 Bis(trifluoromethyl)-2-bromo-2-fluoroethylamine, 80 2.4 

* Results of a 60/40 blend of CCOD's 1392 and 1393 

** NMERI Chemical Compound Options Database ID 

TABLE 1 1. POLYFLUOROAMNE BOILING PONTS. 

~ 

Boiling point, OC (OF) - Formula 

N(CF3)3 -IO 

(CS)zNCF=CFz 13.7 

(CF3) zNCFzCF3 20 to 22 

(CF3) zNCFzCHFz 32.0 

(CF3) zNCBrFz 40.6 

(CF3) zNCFzCBrF2 59.5 to 60.5 

N(CFzCF3) 3 70.3 

CONCLUSION 

Overall the compound search has had very positive results. Bromofluoroalkenes as a class have 

exhibited considerable promise as potential halon replacements and further acquisition of compounds related to 2-bromo-3,3,3-trifluoropropene and 4-bromo-3,3,4,4-tetrdfluorobutene will 

likely lead to the identification of additional low boiling candidates. Continued acquisition and 

testing programs will also include studies of bromofluoroethers and to a lesser extent bromofluoroamines as these two classes of compounds have shown promise in the limited testing 

performed. 

162 Hidon Options Technical Working Conference 2-4 May ZOO0 
ACKNOWLEDGMENTS 

Research efforts on Halon 121 I is supported by Contract PO HQ0038-7350-0007, Defense 

Supply Service-Washington (DSS-W). The authors gratefully acknowledge the support of the 

DOD Next-Generation Fire Suppression Technology Program. funded by SERDP, the US Air 

Force (Tyndall AFB) and Applied Research Associates. The authors also wish to gratefully 

acknowledge the support of the Advanced Agent Working Group whose contributing funders are 

British Petroleum, Exxon, Amoco, US Army, US Air Force, US Navy, and the EPA 

1. 

2. 

3. 

4. 

5. 

6. 

7. 

REFERENCES 

Tapscott, R. E., Heinonen, E. W., and Brabson, G. D., Adi~unc.ed Agent /denrfir.utiori and 

Prrliminur-v Assr.ssnient, Advanced Agent Working Group, November 1996. 

Heinonen, E. W., Lifke. J. L., and Tapscott, R. E., Adi~unced Srreuniin,q Agent Dewlopment, Volrmie IV: Tropodrgruduhle Huloc.ur-hons. NMERI 9614132.540, Vol. 4 of 5. 

Wright Laboratories and Applied Research Associates, Inc., Tyndall Air Force Base, FL, 

April 1996. 

Tapscott, R. E., Rrview urid Assessment of Tropodegruduhle Totul F1oodinLy Agents, Final 

Report, NMERI 96120/32730. Naval Research Laboratory, Washington, DC, August 1996. 

Tapscott, R. E., Mather, J. D., Heinonen, E. W., Moore, T. A,. and Lifke, J. L., To.~icity 

Assessment of Tropodegruduhle Hulorurhoiis, NMERI 9714132930, Wright Laboratories 

and Applied Resedrch Associates, Inc., Tyndall Air Force Base, FL. April 1997. 

Defense Supply Service-Washington (DSS-W) PO HQ0038-7350-0007 and Applied 

Research Associates SEAMAS SSG Task I .4.6, Advanced Streaming Agent Development. 

Gladnick, N. Lawrence, AAWC #87.3. AAWG #YO3. urid AAWG #1116: Bucreriul Re~i~rrse 

Mutution Tcst in Sulmoriellu typhinmriinn und Eschcrichiu coli, Advanced Agent Working 

Group, 2000. 

Chattaway, A., Grigg, J., and Spring, D., “The Investigation of Chemically Active Candidate Halon Replacements,” P rocredings, Halon Options Technical Working Conference, 

Albuquerque, NM, pp. 33-45, 1998