PROGRESS UNDER THE NEXT GENERATION 

FIRE SUPPRESSION TECHNOLOGY PROGRAM IN FYZOOO 

Richard G. Gann 

National lnstitute of Standards & Technology 

INTRODUCTION 

This is a year of transition for the Next Generation Fire Suppression Technology Program (NGP). The 

future funding level has been reduced, and the goal has been modified to “develop and demonstrate, by 

2005, technology for economically feasible, environmentally acceptable and user-safe processes, techniques, and fluids that meet the operational requirements currently satisfied by Halon 1301 systems in 

aircraft.” The NGP strategy has been updated and can be found at the NGP web site: www.dtic.mil/ngpl. 

The demands on the new fire suppression technologies have not lessened, but expectations from the NGP 

were reduced. By FY2001, the NGP would deliver an understanding of how chemicals must interact with 

flames to be as effective as Halon 1301, appraisal of the world of useful chemicals, identification of the 

best places to look for alternative suppressants and a first set of “best looks,” a suite of screening tests, 

and a method for comparing the life-cycle costs of new fire suppression technologies. At the end of 

FY2000, the NGP has completed its fourth year of research, having produced nearly all of these deliverables. The following sections highlight the new knowledge gained from recent NGP research and where 

the research will proceed from this time forward. 

TECHNICAL PROGRESS 

SUPPRESSANT SCREENING TESTS 

The NGP development of a set of efficient, accurate screening tests for new suppressant chemicals has 

been completed. Already published are protocols for progressive evaluation of compounds for 

environmental impact, toxicity, materials compatibility, inhalation toxicity, and fire suppression 

efficiency of gases and liquid aerosols. 

The last screening tool, the Transient Application, Recirculating Pool Fire (TARPF) facility, can simulate 

situations not possible in cup or Tsuji burners: impulsively discharged gases (such as from a pressurized 

storage bottle or solid propellant gas generator, SPGG), the impact of a hot surface on continuous suppression, the impact of a recirculating flow, and the effectiveness of a liquid spray. With the added 

capability to test SPGGs, for the first time both compressed and solid-propellant-generated gases can be 

compared side by side, and the effect on performance of different formulations, particle loadings, and 

burning rates for various SPGG designs can be unambiguously discriminated. The fact that, in Figure 1, 

the agents (chemically or physically active, discharged from an SPGG or a compressed gas bottle) all lie 

close to the theoretical equation shows the value of this new apparatus. 

From computer simulations and related experiments, it was determined that the most difficult fire to 

extinguish results when the flame is anchored to the trailing edge of an obstacle in the flow and is established in the mixing layer between the re-circulation zone immediately behind the step and the main flow. 

The worst case for re-ignition (minimum re-ignition time) occurs when the time required to mix the air 

and fuel is short compared to the time necessary for the fuel surface to cool. 

NGP research has now used a variety of tools to look for candidate agents and understand how they function to quench flames. The latter is especially important, both for considering the potential of agents that 

have not yet been synthesized and for gaining confidence that the chemicals will be effective on the practical fires of concern. We have found that the effectiveness of some types of chemicals varies significantly in different laboratory tests. 

Halon Options Technical Working Conference 24-26 April 2001 I33 
CF3Br 

3 

3L 

i' I 

Figure 1. Comparison ofN,, CF,Br, and SPGG effectiveness in the TARFT 

(1) Experiments with gaseous thermal agents indicate that extinguishing concentrations for diffusion 

flames vary by up to 20% depending on the flow configuration and the fuel, but the relative 

effectiveness of the agents remains fixed. Kinetic modeling of these flames indicates that 

differences in the maximum flame temperature account for the observations. The Dispersed 

Liquid Agent Fire Suppression Screen (DLAFSS) produces the most conservative results. 

(2) Gaseous halogenated agents have shown consistency in the concentrations needed to suppress 

flames in diverse laboratory burners and real-scale tests (notwithstanding the poor performance 

in the SPGG experiments reported below). Thus, any of the laboratory diffusion flames are 

useful to verify that a halogenated chemical is not unusual. The DLAFSS allows examination of 

the added contribution of the heat of vaporization. 

(3) There is disparity in the measured suppression efficiency of "super-effective" chemicals such as 

those containing metal atoms. For instance, modeling and experiments suggested that ferrocene 

in a thermal bath should be a powerful suppressant of practical flames. However, when hot 

product gases from an SPGG passed through a bed of ferrocene and then to a spray flame, the 

combination did not have the intended high efficiency and failed to extinguish the flame. While 

this may be attributed to inefficient delivery of the ferrocene to the flame, further examination at 

laboratory scale seemed warranted. 

(a) Fe(CO), was ineffective at reducing the amount of CO, needed to quench a heptane cupburner flame, while far less Fe(CO), reduced premixed methane-air flame velocity by a 

factor of eight. Similar experiments with the quantity of a CF,Br-CO,, which would halve 

the premixed flame burning velocity, reduced the CO, required for extinction of the diffusion 

flame by a factor of two to three. 

(b) Aqueous solutions of iron, sodium, and manganese salts suppressed flames in the DLAFSS at 

concentrations far below the suppression concentration of pure water. The iron result is 

consistent with the finding from opposed flow diffusion flames, OFDF (which had a higher 

flame strain rate) but at odds with the lower strained cupburner flames. 

134 Halon Options Technical Working Conference 24-26 April 2001 
(c) Phosphorous-containing compounds (PCC) show the same disparate behavior between the 

low strain, co-flow diffusion flame and the higher strain, counterflow diffusion flames, In 

the OFDF and DLAFSS, dimethylmethylphosphonate extinguished the flames at about I% by 

volume. However, extinction of a cup-burner flame by this compound required the addition 

to the air stream of about 5% by volume, about the same extinguishing mass fraction as CO,. 

There are no quantitative data on the effectiveness of PCCs on practical fires. 

(d) Kinetic modeling of inhibited premixed flames provides some circumstantial indication of a 

delicate balance between the thermal and catalytic components of flame quenching. The 

thernial effect lowers the temperature, which leaves the flame radicals further away from 

equilibrium, making catalytic processes more efficient. However, if the temperature gets too 

low to permit adequate generation of the catalytic species from the parent compound in the 

available amount of time, the suppression efficiency will be diminished, not enhanced. Thus, 

for flame geometries in which suppressants will have short residence times in the flame zone, 

the rate and temperature at which the catalytic species is released is a critical property of a 

prospective agent. This will be especially important for suppressants added as droplets or 

solid particles. 

Resolving the issue of the proper laboratory burner(s) for screening candidate suppressants is a priority 

for FY2001 research. 

NEW FLAME SUPPRESSION CHEMISTRY 

There are a large number of families of chemicals, and the NGP is working systematically to ensure 

examination of all pertinent compounds. The principal desirable properties guiding the search are the 

following: 

Fire suppression efficiency at least comparable to Halon 1301 and certainly higher than HFCs 

Short atmospheric lifetime (current preference ofthe order of a month), to keep ozone depletion, 

global warming, and any future unidentified environmental contamination issues to a minimum. 

Low toxicity relative to the concentration needed for suppression. 

Boiling point sufficiently low that for gaseous agents, an extinguishing concentration can be 

achieved within a specified time following discharge. A tentative upper limit is 80 "C, but slow 

evaporation or poor dispersion may reduce this significantly. 

Previous NGP research had established the value of compounds that contain both a bromine atom for fire 

suppression efficiency and an additional feature that leads to rapid degradation of the compound in the 

troposphere. From a list of over 80 promising chemicals, four have emerged as particularly encouraging: 

l-bromo-3,3,3-trifluoropropene, Z-bromo-3.3,3-trifluoropropene, 4-bromo-3,3,4,4-tetrafluorobutene, and 

Z-brorno-3,3,4,4,4-pentafluorobutene. New computational techniques indicate that the atmospheric lifetimes of these compounds are 4 to 8 days; their measured flame suppression efficiencies are comparable 

to other brominated chemicals. Evaluation of various toxicity properties for these compounds, pursued 

by the Advanced Agent Working Group, has been positive. 

The main caution with these chemicals for aircraft use is their high boiling points. Prior research had 

indicated problems dispersing chemicals with boiling points of about -20 'C when the storage container 

and the environment are as low as -40 "C, a design specification for fire suppressants in aircraft. NGP 

research is underway to determine whether CFJ (with a boiling point of -22 "C) will disperse well. if 

CFJ floods the volume efficiently, the developed test procedures will be used to examine higher boiling 

chemicals. Meanwhile, a rigorous search is underway to identify and procure for testing additional 

bromofluoroalkenes, bromofluoroamines, and bromofluoroethers with significantly lower boiling points. 

Halon Options Technical Working Conference 24-26 April 2001 135 
Prior NGP research had demonstrated the high flame quenching efficiency of PCCs in an opposed flow 

diffusion flame. New results show that the suppression efficiencies of PCCs are determined by the 

number of phosphorus atoms delivered to the flame with little sensitivity to the bonding environment. 

Detailed chemical modeling of the flame with added DMMF' shows that the concentrations of the key 

P-containing radicals reach a plateau before an extinguishing concentration is reached. This further 

supports the concept that while small amounts of agent may reduce flame radicals to equilibrium levels, 

additional added heat capacity is needed to effect extinction. 

To date, NGP research has investigated several chemical families as sources of alternative fire suppressants. With this enhanced knowledge, a comprehensive review of the world of chemicals has now been 

performed to identify those chemical families most ripe for examination in the NGP. Assessments were 

made of the extent of prior fire suppression studies and the potential for success in any (further) study. 

Expected flame suppression efficiency, atmospheric persistence, boiling point, and toxicity were the main 

screening criteria. The following families were identified as the most promising: amines and nitriles; 

phosphorus-containing acids, esters, nitriles and halides; sulfides, mercaptans and sulfoxides; manganese 

and tin compounds; iodinated alkenes; and brominated or iodinated ethers. It is expected that substantial 

fluorination would be needed to obtain the desired low boiling points. 

NEW AND IMPROVED AEROSOL SUPPRESSANTS 

Nearly all suppressants of interest emerge from pressurized storage containers as liquids or powders, 

along with a gaseous component. NGP research has already shown that the properties of the dispensed 

aerosol can have a profound effect on the mass of suppressant needed to quench flames. The work this 

year has proceeded in two directions. 

(I) The first involves improving the effectiveness of water-based aerosols. Since water dispersion 

and vaporization are problematic at the lower temperatures experienced hy aircraft in flight, the 

NGP will not pursue this aspect in future years. 

(a) A picture has emerged of the suppression of opposed flow diffusion flames by water 

droplets. On a mass basis, water droplets can be at least as efficient as gaseous Halon 1301. 

The transition from very effective, smaller droplets to larger, less effective ones depends on 

the aerosol boiling or decomposition temperature, the density of the liquid or solid, the local 

temperature, and the residence time of the aerosol at that temperature. 

(b) NGP research has pursued the use of additives to water to increase its effectiveness and 

lower the freezing point. While calculations indicated that lactic acid, a compound with a 

high heat of vaporization, might reduce the mass of water required for extinguishment, 

measurements in the DLAFSS revealed it had the opposite effect. The enhanced heat 

extraction is outweighed by the lactic acid's contribution as a fuel. 

(c) The strain rate (defined in terms of the velocities of the air and fuel streams, their densities, 

and a characteristic length) is a flame property that enables relating laboratory burners to 

actual fires. Velocities are difficult to measure for aerosol-laden air streams in which the 

particles or drops in the air stream carry a substantial amount of momentum, but the individual particles or drops may be too large to follow the gas flow. NGP research has developed a technique for measuring the true air stream velocity by saturating (to minimize evaporation) the air with fine (<I gm diameter) droplets and following their movement using 

Phase Doppler Particle Anemometry. However, at water suppressant loadings over 5% by 

mass, the local strain rate is strongly affected; work continues to develop a suitable metric. 

(2) The NGP is exploring the concept of storing effective but otherwise harmful chemicals stably in a 

safe medium, which would then release the chemical when the medium was discharged and 

reached the high-temperature neighborhood of the flame. 

I36 Halon Options Technical Working Conference 24-26 April 2001 
(a) Last year, NGP research had shown that it is possible for an inert host to transport a practical mass of a suppressant to the fire. The remaining question was the speed of release in 

the flame. We have now designed and tested a system for introducing the host particles into 

premixed and counterflow diffusion flames. We established a good correlation between the 

inhibition effects of NaHCO, in premixed and diffusion flames despite the significantly 

different structures of these flames. Hence, we expect that tests with two flames should be 

comparable in demonstrating the release of chemically acting agents. 

(b) The original intent to try Fe(CO), as the adsorbed suppressant will not be fulfilled. While 

several hosts absorbed significant Fe(CO),, they also all showed reaction of the absorbed 

agent when exposed to air, making it unavailable to provide the gas phase Fe required for 

efficient flame inhibition. Consideration of other metal-containing compounds may also be 

unwarranted if, as noted earlier, they prove ineffective on practical flames. Fortunately, the 

zeolites can absorb about 25% by mass of either Br, or I,. Their release from these particles 

will be tested soon. 

IMPROVED SUPPRESSANT DELIVERY 

Improving the efficiency of getting the suppressant to the site of the tire is as important as finding new 

agents. Last year, the NGP completed and validated a new computer code for prediction of two-phase 

fire suppressant flows during discharge, enabling appraisal of a new suppressant’s compatibility with 

existing distribution plumbing. The focus of the research has now progressed to storage and discharge 

technology and transport once the agent has been dispensed from the system hardware. 

NGP research is developing new SPGGs that have both reduced combustion temperatures and increased 

flame suppression efficiency, which in turn will enable suppressant stream momentum reduction. A first 

set of propellant compositions designed to produce cooler effluent was based upon novel high-energy, 

high-nitrogen fuels: 5-aminotetrazole and C,H,N,,. They were formulated with potassium perchlorate or 

strontium nitrate oxidizer and an elastomeric binder. Gas temperatures were reduced in some cases by 

IO to 20% relative to a state-of-the-art chemically inert formulation. Lower levels of oxidizer or the use 

of different oxidizers will likely reduce the temperature further while maintaining high nitrogen generation. Compositions incorporating combustion inhibitors (decabromodiphenyl oxide [DBDPO], KNO,, 

K,CO,, Fe,O,) were burned efficiently and were effective in fire suppression. 

Exploratory tests were also conducted to bound the mass of an entrained fire suppressant needed to suppress a 1 MW JP-S/air spray flame. The agents were loaded inside the discharge section of a neutralburning SPGG (Figure 2), whose exhaust consisted mainly of CO,, N,, and H,O. During SPGG discharge, the agents were to be vaporized and delivered into the fire zone by the high pressure, high 

temperature exhaust gases. About 40 g of either KI or K?CO, was sufficient to suppress the flames. 

Flames were not suppressed by the addition of 40 g of iron oxalate, by 60 g of KBr or DBDPO, or by 

80 g of Fe,O, or ferrocene. Based on the distinctive colors imparted to the flames by several of the 

impinging agents, the powders seemed to be ejected out of the SPGG throughout the test duration of 

about 8 seconds. In the ferrocene tests, needle-shaped ferrocene crystals were deposited on the exit port 

of the delivery tube. 

The similarity in performance between KI and K,CO, reflects that observed in turbulent spray burner 

tests. This likely reflects the lead role of the potassium ion in suppression effectiveness rather than the 

anion. The cause of the reduced effectiveness of KBr relative to KI is unknown. It is also difficult to 

understand why the bromine-laden DBDPO and the iron compounds appear ineffective, although the 

ferrocene crystals at the SPGG exit implies that not all of the agent is reaching the flame. Additional 

work is planned to quantify the mass of agent reaching the flame and improve the agent delivery. 

Halon Options Technical Working Conference 24-26 April ZOO1 137 
<,. , Agentexhaust 

Matrix containing 

f-Chamber1 

Figure 2. Solid Propellant Gas Generator Test Unit. 

The Navy and Air Force aircraft safety and survivability teams have verified the expectation that improved location and styling of discharge sites can significantly reduce the mass of agent needed to control a 

fire in an engine nacelle. The NGP is developing a systematic approach to support such design modifications for all aircraft nacelles using a validated computational fluid dynamic (CFD) model of suppressant 

flow, a fire, and fire extinguishment in cluttered environments. 

To establish a baseline, CFD predictions were compared with detailed measurements in a quarter-scale, 

smooth nacelle fixture (Figure 3) under well-controlled conditions. Velocity and turbulent intensity 

profiles were obtained using hot wire anemometry and Laser Doppler Anemometry (LDA). Two CFD 

models, VULCAN and CFD-ACE, ably predicted the velocity and turbulence intensity for regions away 

from the wall. Near-wall discrepancies are likely due to the rectangular mesh in VULCAN and the small 

velocities near the walls that serve to increase the uncertainty in both the models and the data. 

Figure 3. Quarter-Scale Simulator with LDA test setup. 

Representative forms of clutter have been selected for both the models and the test fixture: cylinders to 

simulate long runs of tubing and body-centered cubes of spheres for the random shaped clutter. The area 

blockage factor or the volume percent of the spheres will match that of the actual hardware clutter. The 

subgrid clutter packages have been completed and the experimental plan defined. 

Including aerosol agents in such a model requires data on the change in flow behavior as the dropletladen stream moves around obstacles: measurement of gas mean and turbulent velocity data both 

upstream and downstream of the obstruction. Accordingly, an existing spray facility has been modified 

to enable measurements of a well-characterized, closely isotropic turbulent flow field around a prescribed 

obstacle. The flows will be characterized using planar imaging velocimetry and phase Doppler 

interferometry. 

138 Halon Options Technical Working Conference 24-26 April 2001 
Quenching a fire in an engine nacelle requires maintaining a sufficient concentration of agent in the flame 

zone for a sufficient time interval while a forced air flow through the nacelle is sweeping the suppressant 

out the exhaust. A novel approach to achieving the residence time with a smaller amount of suppressant 

is to reduce the cross sectional area of the nacelle, in the event of a fire, by strategic placement of an intumescent material (Figure 4). These materials are coatings that respond to the impingement of heat by 

swelling a factor of IO or more. Since the width of the (irregular) annular air passage is commonly 110 

more than 3 cm - 10 cm, an appreciable reduction in airflow through the nacelle could be achieved Such 

a local fire block would weaken the fire due to oxygen starvation (by constricting airflow). By reducing 

the mass of suppressant needed, the constriction could even lead to extinguishment by itself. 

Flame 

Intumescent Ventilation Airflow 

Material 

Figure 4. Use of an intumescent coating to reduce engine nacelle airflow. 

We have identified over 80 manufacturers of intumescent materials for other flame stop applications and 

are reviewing the product data for durability of the coating during uormal flight operations; adhesion and 

vibration-resistance of the expanded char following activation of the paint by a fire; effectiveness of the 

coatings, including the expected expansion rate and the fraction of the nacelle flow reduced by the coating; and ability to apply the coatings to the nacelle. Data on current aircraft engine nacelles are being 

obtained to help determine the specific properties of a successful intumescent coating: areas of minimal 

clearance, potential material compatibility issues), airflow requirements in the engine nacelle, etc. These 

will enable an estimate of the decreased oxygen and/or increased suppressant residence time that would 

result from a given constriction in airflow. This research will in turn lead to an estimate of the reduction 

in suppressant needed as a result of using this technology. 

VIABILITY OF NEW SUPPRESSANT TECHNOLOGIES 

Research has been completed on a portable instrument for measuring agent concentration with a IO ms 

time response, fast enough for quantification of the transient agent concentration during the suppression 

of the fastest fires involving military systems. The Differential Infrared Agent Concentration Sensor 

(DIRRACS-2) was tested in a series of HFC-125 discharges carried out in a Bradley armored personnel 

carrier. All of the releases were from a high position just behind the turret. The concentration was 

monitored either near head height or waist height for an occupant of the vehicle. Figure 5 shows the 

ability to track the agent concentration; the fluctuations are due to turbulence. 

A large number of contributing factors must be considered when making a decision whether or not to 

retrofit a fire suppression system, including both objective cost factors and subjective value factors. 

Accordingly, the NGP has developed a methodology to quantify a fire suppression technology by its total 

life cycle cost and to enable superimposing a subjective value system on this. The methodology determines the net cost of the fire suppression system: the cost ofthe system (which is a function of system 

size/weight) minus the cost savings provided by the system (which are a function of extinguishant effectiveness and result in aircraft saved). An initial case study was developed for the nacelles in C- I7 aircraft 

for the existing Halon 1301 system and a system of equal performance using an off-the-shelf-alternative, 

HFC-125. Actual data were used to characterize the Halon 1301 system on the C-17. 

llalon Options 'Technical Working Conference 24-26 April 2001 139 
::::: :::: ::.:: :.:: 

-:::: :::: . . . . . . . . . . , . . . . . . 

0 0.5 1 1.5 

Time, s 

Figure 5. Agent concentrations from two releases of 3.5 kg of HFC-125. 

Design estimates for a HFC-125 system were based on information developed in experiments conducted 

under the DoD Technology Development Plan for Alternatives to Ozone-Depleting Substances for Weapon Systems Use. System costs were derived from data provided by the Defense Logistics Agency, the 

C-17 Program Office, and engineering estimates. Uncertainties resulted from the lack of historical 

information over the life ofthe C-17 aircraft and the non-existence of a fielded HFC-125 system. 

The estimated total costs of ownership of the Halon 1301 or HFC-125 systems in the current fleet of C-I7 

aircraft are close to each other and about one tenth of one percent of the total (life cycle) cost of the aircraft. The benefit of having either fire suppression system far outweighs its cost, and the difference in 

total cost of the two systems is modest compared to the total cost of owning and operating the aircraft. 

The project will continue with extension of the methodology to nacelles in the F/A-18 E/F and a rotary 

wing platform and a dry bay application. 

IMPROVED FUEL TANK INERTION 

Research in this area has been limited. Only two aircraft currently use Halon 1301 to inert fuel tanks 

when entering combat: F-16 and F-117. The Air Force is considering the use of CF,I for this application. 

If this decision is positive, then alternative technologies for fuel tank inerting will not be an NGP task. 

As an exploratory measure, the NGP has assessed the current status of alternate systems that had in prior 

decades shown promise for fuel tank inerting. An extensive literature search identified 25 such systems 

and characterized them, with regard to, e.&, their latest status, any history of testing or use, and any concerns with their implementation. The most viable of these are the LFE (Linear Fire Extinguisher) and the 

PRESS (Parker Hannifin Reactive Explosion Suppression System). Each has advantages that outweigh 

the disadvantages, and the LFE and PRESS were deemed capable of being overcome with further development. 

WHAT LIES AHEAD? 

Because of the substantial technical accomplishments in its initial years, the NGP has a solid base from 

which to develop new fire suppression technology for weapons systems. From this point forward, the 

NGP will be directed toward two targets. 

140 Halon Options Technical Working Conference 24-26 April 2001 
NEW FLAME SUPPRESSION CHEMICALS 

NGP research will complete its review of the world of chemicals in looking for alternatives to CF3Br. 

Research into each of these chemical families will identify trends in suppression effectiveness, toxicity, 

etc., using NGP screening methods and quantitative structure-activity relationships from prior work. The 

optimal candidates will be flagged for further development. Full toxicological examinations will not be 

performed. A few real-scale tests will be conducted to demonstrate the reliability of the bench-scale 

results as a predictor of the success of agents, rather than full characterization of the performance of all 

candidate agents. 

IMPROVED SUPPRESSANT STORAGE AND DELIVERY 

NGP research has developed basic principles for the relationship between suppressant flow properties and 

the enhanced concentrations needed for the quenching of flames in cluttered spaces. The research has 

also shown the importance of the location (relative to the flame) where a suppressant fluid vaporizes. 

What remains is completion of the understanding of the interactions between the suppressant flow and the 

fire in cluttered spaces. This will serve as a guide for the selection of optimal dispensing conditions, 

nozzle locations, etc., for effective suppression of fires in the various engine nacelle and dry bay configurations. Further work will also develop new ways of positioning the suppressant and controlling its discharge properties, approaches complementary to the traditional pressurized fluid bottles. Combined, 

these will then constitute a set of source terms for the above models and offer flexibility and efficiency to 

the platform designer. These models and technologies will be turned over to the platform managers for 

optimization testing in their particular configurations. 

ADDITIONAL EFFORTS 

Over the past four years, the NGP has solicited proposals for “outside the box” approaches to fire suppresion. Some of these novel ideas have proven successful at broadening the NGP thinking. A modest continuation of these solicitations is possible. Much of the innovation in NGP projects has resulted from 

interactions among a large set of investigators in diverse but related aspects of fire suppression. The 

NGP will continue to co-sponsor and participate actively in the spring Halon Options Technical Working 

Conference (29 April-2 May 2002). The NGP will broaden the participation in its autumn Annual 

Research Meeting, inviting past investigators and other experts. It is hoped that these two meetings will 

continue to broaden the perspective and stimulate the innovation of the NGP investigators. 

SELECTED RECENT PUBLICATIONS 

General 

Suppressant Screening Tests 

Gam, R.G., FY2000 Annual Report: Next Generation Fire Suppression Technology Program (NGP), 

NlST Technical Note 1437, National Institute of Standards & Technology, Gaithersburg, MD, 2001. 

Grosshandler, W.L., Hamins, A,, Charagundla, S.R., and Presser, C., “Suppression Effectiveness 

Screening for Impulsively Discharged Agents,” Proceedings, Halon Options Technical Working 

Conference, Albuquerque, NM, pp. 15-25,2000, 

Jomaas, G., Roberts, B.T., DuBois, J., and Torero, J.L., A Study of the Mechanisms Leading to Reignition in a “Worsl Case” Fire Scenario, Final Report, Cooperative Agreement 70NANB8H0043, 

Department of Fire Protection Engineering, University of Maryland College Park, MD, June 2000. 

Grosshandler, W.L., Hamins, A., McGrattan, K., Charagundla, R., and Presser, C., “Suppression of a 

Non-premixed Flame Behind a Step,” Proceedings of the Combustion Institute 28, pp. 2951-2964, 

2001. 

Takahashi, F., Schmoll, W.J., Strader, E.A. and Belovich, V.M., “Suppression of a Nonpremixed 

Flame Stabilized by a Backward Facing Step,” Combustion andFlame 122, 105-1 16,2000. 

Halon Options ‘Technical Working Conference 24-26 April 2001 141 
Yang, J.C., Donnelly, M.K., PrivC, N.C., and Grosshandler, W.L., “An Apparatus for Screening Fire 

Suppression Efficiency of Dispersed Liquid Agents, “Fire Safety Journal, Vol. 36, pp. 55-72,2001, 

Vinegar, A,, Jepson, G., Cisneros, M., Rubenstein, R., and Brock, W., ‘‘Sethg Safe Exposure Limits 

for Halon Replacement Chemicals Using Physiologically-based Pharmacokinetic Modeling,” Inholation Toxicology 12, pp. 751-763,2000. 

Vinegar, A., “Toxicological Assessment of Human Health Consequences Associated with Inhalation 

of Halon Replacement Chemicals,” Final Report to the Next Generation Fire Suppression Technology Program, 2000. 

Vinegar, A,, “Modeling Cardiac Sensitization Potential of Humans Exposed to Halon 1301 and Halon 

121 1 Aboard Aircraft,” Aviation, Space, and Environmental Medicine, in press, 2001. 

Vinegar, A,, “PBPK Modeling of Canine Inhalation Exposures to Halogenated Hydrocarbons,” Toxicological Sciences, Vol. 60, pp. 20-27,2001, 

Dodd, D.E., Jepson, G.W., and Macko, J.A., Jr., “Human Health Safety Evaluation of Halon Replacement Candidates,” Air Force Technical Report, AFRL-HE- WP-TR-2000-0104,2000. 

Nyden, M.R., Yang, J.C., and Mather, J.D., “Screening of Candidate Fire Suppressants,” Proceedings, Halon Options Technical Working Conference, Albuquerque, NM, pp. 104-1 15,2000. 

New Flame Suppression Chemistry 

Tapscott, R.E., and Mather, J.D., “Tropodegradable Fluorocarbon Replacements for Ozone Depleting 

and Global Warming Chemicals,” Journal of Fluorine Chernisfry 101, pp. 209-213,2000, 

Mather, J.D., and Tapscott, R.E., “Tropodegradable Bromocarbon Extinguishants: Progress Overview,” Proceedings, Halon Options Technical Working Conference, Albuquerque, NM, pp. 154- 163, 

2000. 

Orkin, V.L., Villenave, E., Huie, R.E., and Kurylo, M.J., “Atmospheric Lifetimes and Global Warming Potentials of Hydrofluoroethers: Reactivity Toward OH, UV Spectra, and IR Absorption Cross 

Sections,”J. Phys. Chem. A 103, pp. 9770-9719, 1999. 

Louis, F., Gonzalez, C., Huie, R. E., and Kurylo, M. J., “An Ab initio Study of the Reaction of Halomethanes with the Hydroxyl Radical. Part 1: CH,Br,,”J. Phys Chem. A 104,293 1-2938,2000. 

Louis, F., Gonzalez, C., Huie, R. E., and Kurylo, M. J., “An Ab initio Study of the Kinetics of the 

Reactions of Halomethanes with the Hydroxyl Radical. Part 2: A Comparison between Theoretical 

and Experimental Values of the Kinetic Parameters for 12 Partially Halogenated Substituted 

Methanes,” J. Phys Chem. A 104, pp. 8773-8778,2000. 

Louis, F., Gonzalez, C., Huie, R. E., and Kurylo, M. J., “An Ab initio Study of the Kinetics of the 

Reactions of Halomethanes with the Hydroxyl Radical. Part 3: Reactivity Trends and Kinetics 

Parameter Predictions for the Potential Halon Replacements CH,FBr, CHFBr,, CHFCIBr, CHCI,Br, 

and CHCIBr,”J. Phys. Chem. A, Vol. 105, pp. 1599-1604,2001. 

Huie, R. E., Louis, F., Gonzalez, C. A,, and Kurylo, M. J., “An Ab initio-Based Screening Tool for 

the Atmospheric Lifetimes of Halon Replacements,” Proceedings, Halon Options Technical Working 

Conference, Albuquerque, NM, pp. 87-92,2000. 

Yang, J.C., Cleary, T.C., and Donnelly, M.K., “Performance Data on Cold Temperature Dispersion 

of CF31,’’ Proceedings, Halon Options Technical Working Conference, Albuquerque, NM, pp. 175- 

179,2000. 

Williams, B.A., and Fleming, J.W., ”Influence of Bond Energies on Chemical Flame Inhibition: 

Implications for the Search for New Fire Suppressants,” (submitted for publication), copy on file with 

the author, 2000. 

Babushok, V., Tsang, W., and Grosshandler, W.L., “Inhibitor Rankings for Hydrocarbon Combuution,” Combustion andFlume, Vol. 123, pp. 488-506,2000. 

Fuss, S.P., Dye, D.J., Williams, B.A., and Fleming, J.W., “Inhibition of Premixed Methane-Air 

Flames by Submicron Water Mists,” Proceedings, Halon Options Technical Working Conference, 

Albuquerque, NM, pp. 242-250,2000. 

142 Halon Options Technical Working Conference 24-26 April 2001 
Babushok, V., and Tsang, W., “Influence of Phosphorus-Containing Fire Suppressants on Flame 

Propagation,” Proceedings ofthe Third Jnlernational Conference on Fire Research und Engineering, 

pp. 257-267, Chicago, IL, 1999. 

Yang, J.C., Bryant, R.A., Huber, M.L., and Pitts, W.M., “Experimental Investigation of Extinguishment of Laminar Diffusion Flames by Thermal Agents,” Proceedings, Halon Options Technical 

Working Conference, Albuquerque, NM, pp. 433-446, 2000. 

New And Improved Aerosol Suppressants 

Zegers, E.J.P., Williams, B.A., Sheinson, R.S., and Fleming, J.W., “Dynamics and Suppression 

Effectiveness of Monodisperse Water Droplets in Non-Premixed Counterflow Flames,” Proceedings 

of the Combustion Institute 28, pp. 293 1-2938,2001. 

Zegers, E.J.P., Williams, B.A., Sheinson, R.S., and Fleming, J.W., “Water Mist Suppression of 

MethanelAir and PropanelAir Counterflow Flames,” Proceedings, Halon Options Technical Working 

Conference, Albuquerque, NM, pp. 25 1-261, 2000. 

Rumminger, M.D., and Linteris, G.T., “Numerical Modeling of Inhibition of Counterflow Diffusion 

Flames by Iron Pentacarbonyl,” Proceedings of /he Sixlh Internutional Symposium on Fire Safely 

Science, International Association for Fire Safety Science, pp. 289-300, 2001. 

Rumminger, M.D., and Linteris, G.T., “Inhibition of Premixed Carbon Monoxide-Hydrogen-OxygenNitrogen Flames by Iron Pentacarbonyl,” Combustion andF/ame 120, pp. 45 I-464,2000. 

Linteris, G.T., and Rumminger, M.D., “Premixed Carbon Monoxide/Nitrous Oxide/Hydrogen 

Flames: Measured and Calculated Burning Velocities With and Without Fe(CO),,” Combuslion and 

Flame 122, pp. 58-75,2000. 

Rumminger, M.D., and Linteris, G.T., “The Role of Particles in Flame Inhibition by Iron Pentacarbonyl,” Combustion undFIame 123, pp. 82-94,2000. 

Linteris, G.T., Rumminger, M.D., Babushok, V.I., and Tsang,W., “Flame Inhibition by Ferrocene and 

Blends of Inert and Catalytic Agents,” Proceedings ofthe Combustion Institute 28, pp. 2965-2972, 

2000. 

Rumminger, M.D., and Linteris, G.T. “Particle Formation in Counterflow Diffusion Flames Inhibited 

by Iron Pentacarbonyl,” Combustion and Flame, in press, 2001. 

Improved Suppressant Delivery 

Takahashi, F., Schmoll, W.J., Strader, E., and Belovich, V.M., “Suppression of Nonpremixed Flame 

Stabilized by a Backward-Facing Step,” Combustion andFlame, Vol. 122, pp. 105-1 16,2000. 

Fallis, S., Reed, R., Lu, Y.C., Wierenga, P.H., and Holland, G.F., “Advanced PropellanUAdditive 

Development for SPGG Fire Suppression Systems,” Proceedings, Halon Options Technical Working 

Conference, Albuquerque, NM, pp. 277-281,2000. 

Bennett, M.V., “A Method for Extinguishing Engine Nacelle Fires by Use of Intumescent Coatings,” 

Proceedings, Halon Options Technical Working Conference, Albuquerque, NM, pp. 277-281, 2000. 

Mulholland, G.W., Johnson, E.L., Fraser, G.T., Zuban, A.V., andLeonov, 1.1., “Performance ofFast 

response Agent Concentration Meter,” Proceedings, Halon Options Technical Working Conference, 

Albuquerque, NM, pp. 480-491,2000, 

Bennett, M.V., “Relative Benefit Assessment Of Fire Protection System Changes,” Proceedings, 

Halon Options Technical Working Conference, Albuquerque, NM, pp. 26-3 I, 2000. 

Bennett, M.V., “Providing the Technical and Business Solutions,” SURVJAC Bulktin XV(3), Fall 

1999. 

Bennett, M.V., “Review of Technologies for Active Suppression for Fuel Tank Explosions,” 

Proceedings, Halon Options Technical Working Conference, Albuquerque, NM, pp. 3 14-323,2000, 

Viability of New Suppressant Technologies 

Xmproved Fuel Tank Inertion 

Halon Options Technical Working Conference 24-26 April 2001 143