Analysis of the Coordination of Suppression and Ventilation in Single-Family Homes

2020 ◽  
Author(s):  
Jack Regan ◽  
◽  
Julie Bryant ◽  
Craig Weinschenk
Keyword(s):  
Water Distribution ◽  
Fire Service ◽  
Lessons Learned ◽  
Positive Pressure ◽  
Water Application ◽  
Single Family ◽  
Surface Cooling ◽  
Initial Application ◽  
Alternative Means ◽  
The Impact

Prior full-scale research with the fire service was primarily designed to isolate specific tactics, most often either ventilation or suppression, which allowed researchers to develop science-based recommendations related to the specific components of fireground operations studied in relatively controlled conditions. The current project went beyond earlier research by conducting twenty experiments in eight acquired, single-family residential structures and that combined fireground tactics to quantify the impact of coordination between ventilation and suppression actions. This experimental series included second-story bedroom fires (14 experiments) and first-floor kitchen fires (6 experiments). The main control variables studied included the position of initial application of water, the ventilation method, and the timing of ventilation relative to water application. The ventilation tactics examined in these experiments included horizontal, vertical, positive pressure, and hydraulic ventilation, while the suppression tactics included both interior water application and initial exterior water application followed by interior water application. While some elements of the experiments (e.g. structure floor plan and weather) resulted in increased variability, the lessons learned highlighted the importance of having a systematic approach to the implementation of tactics. Most importantly, there was no meaningful increase in temperature outside of fire rooms when ventilation tactics were executed in coordination with (shortly after or shortly before) the onset of suppression. The effectiveness of suppression actions in extinguishing the fire were dependent on the ability of those actions to 1) cool surfaces in the fire room and 2) wet unburned fuel. Exterior suppression actions on second-floor bedroom fires resulted in a decrease in temperatures throughout the second floor, followed by regrowth prior to final suppression through interior streams. When exterior suppression was performed on first-floor kitchen fires, where more complete fuel wetting was possible, regrowth was not observed prior to interior suppression. When surface cooling or fuel wetting are not possible due to the elevation of the fire room, missing ceiling, or obstacles, firefighters should consider alternative means of water distribution to improve the effectiveness of suppression actions from outside the fire room. Suppression actions, whether interior or exterior, generally resulted in a decrease in temperatures and gas concentrations at locations where occupants may potentially be located. Conditions improved most quickly at locations closest in proximity to the inlet of the flow path established between the front door and the fire room. For this reason, opening an exterior door to gain access should be thought of as an important ventilation action, both in terms of its potential to cause fire growth and its potential to improve conditions for potentially trapped occupants. After effective suppression, structure ventilation operations should similarly be cognizant of gas flows, with the aim of establishing flow throughout all areas where occupants may be located.

Analysis of the Coordination of Suppression and Ventilation in Multi-Family Dwellings

2020 ◽  
Author(s):  
Keith Stakes ◽  
◽  
Keith Stakes ◽  
Julie Bryant ◽  
Nick Dow ◽  
...  
Keyword(s):  
Fire Service ◽  
Service Research ◽  
Positive Pressure ◽  
Living Room ◽  
Gas Flows ◽  
Water Application ◽  
Single Family ◽  
Smoke Movement ◽  
Family Structures ◽  
The Impact

The majority of the existing full-scale fire service research studied the impact of tactics on the residential fireground, specifically in single-family structures. This study builds upon prior research by conducting thirteen experiments in three-story, multi-family dwellings to quantify the impact of coordination between ventilation and suppression actions. Experiments were conducted in four, garden-style apartment buildings; each of which had two lower-level units, four first-floor units, and four second-floor units. The apartments shared a common stairwell that was enclosed for all of the experiments in this study. To examine the effectiveness of tactics in the fire apartment, common stairwell and applicable exposure apartments, four experiments were conducted in lower-level apartments, seven were conducted in first-floor apartments, and two were conducted in second-floor apartments including both bedroom and kitchen/living room fires. The fire size varied based on the amount of initial ventilation provided. The main control variables included the location of initial water application, the ventilation method, and the timing of ventilation relative to water application. The suppression tactics included interior water application, exterior water application followed by interior water application, and a combined interior and exterior water application. The ventilation tactics examined in these experiments included horizontal, vertical, positive pressure, and hydraulic ventilation. Similar to previous experiments in acquired single-family structures, there was no meaningful increase in temperature outside of fire rooms when ventilation tactics were executed in close coordination with (shortly after or shortly before) the onset of suppression. In contrast, for experiments where ventilation occurred with delayed suppression, temperature exposures increased throughout the fire apartment, and in experiments where the apartment door was left open, temperatures and carbon monoxide exposures increased throughout the common stairwell. Suppression actions, whether interior or exterior, resulted in a decrease in temperatures and gas concentrations at locations where occupants may potentially be located. The enclosed common stairwell, a unique feature of this experimental series, acted as capture of combustion products. Opening the apartment door to gain access should be thought of as an important ventilation action, both in terms of its potential to cause fire growth and its potential for smoke movement into the stairwell, limiting the egress for potentially trapped occupants in exposure units. Tactics such as door control, positive pressure ventilation, and hydraulic ventilation which were used both simultaneous with and sequentially post-suppression were shown to limit gas flows into the stairwell. After effective suppression, structure ventilation operations should similarly be cognizant of gas flows, with the aim of establishing flow throughout all areas where occupants may be located.

scholarly journals Impact of Fire Attack Utilizing Interior and Exterior Streams on Firefighter Safety and Occupant Survival: Water Mapping

2017 ◽  
Author(s):  
Craig Weinschenk ◽  
◽  
Keith Stakes ◽  
Robin Zevotek
Keyword(s):  
Water Distribution ◽  
Scientific Information ◽  
Air Entrainment ◽  
Fire Service ◽  
Full Scale ◽  
Single Family ◽  
Fire Dynamics ◽  
Firefighter Safety ◽  
The Impact ◽  
Fire Ground

As research continues into how fire department interventions affect fire dynamics in the modern fire environment; questions continue to arise on the impact and implications of interior versus exterior fire attack on both firefighter safety and occupant survivability. Previous research into various types of fire ground ventilation, flow paths, and exterior fire streams has provided the fire service with an increased understanding of fire dynamics. However, in some instances, the information from the studies may not support current, experienced-based practices. This gap between the research to date and the fire ground suppression experience has driven the need for further study. Therefore, research into the various methods of fire attack will allow a broader understanding of how firefighter interventions on the fire ground can impact the outcome of both life safety and property protection. This study will build upon the fire research conducted to date by analyzing how firefighting tactics, specifically different fire suppression tools and tactics, affect the thermal exposure and survivability of both firefighters and building occupants and affect fire behavior in structures. The purpose of this study is to improve firefighter safety, fireground tactics, and the knowledge of fire dynamics by providing the fire service with scientific information, developed from water flow and full-scale fire testing, in representative single-family homes. The project will be comprised of 3 parts: • Part I: Water Distribution • Part II: Air Entrainment • Part III: Full-Scale Residential Fire Experiments This report details the results and analysis from the water distribution experiments. These tests were conducted without the presence of fire to gain a fundamental understanding of water flows into compartments. Each test was designed to quantify water distribution within a compartment by evaluating the differences caused by various application methods, hose stream types, nozzle movements, pressures/flow rates, stream locations and elevation angles.

Performance of lifelines during the 1994 Northridge earthquake

1995 ◽  
Vol 22 (2) ◽  
pp. 438-451 ◽  
Author(s):  
David L. Lau ◽  
Alex Tang ◽  
Jean-Robert Pierre
Keyword(s):  
Los Angeles ◽  
Electric Power ◽  
System Performance ◽  
Water Distribution ◽  
Lessons Learned ◽  
Northridge Earthquake ◽  
Epicentral Area ◽  
Lifeline Systems ◽  
Earthquake Damages ◽  
The Impact

Lifelines are essential infrastructures and facilities that are considered vital to the rescue effort and recovery of the affected community in the event of a natural disaster or emergency. The lifeline systems in a densely populated area, such as the Los Angeles basin, are very complex. The Northridge earthquake, which occurred in southern California on January 17, 1994, caused extensive damage to many of these lifeline facilities in the epicentral area. Effects of the damages were felt not only in the vicinity area of the earthquake but also in areas far from the earthquake site. This paper describes the earthquake damage to and performance of gas and water distribution and electric power and telecommunication systems. The impact of these failures on the overall system performance are presented. The significance and effect of the interdependency of life systems in an integrated urban environment are discussed. Lessons learned on system performance, seismic risk, and reliability of lifeline systems from the Canadian perspective are presented. Key words: earthquake damages, electric power, gas, lifelines, performance, risk, telecommunication, water.

Fire Service Summary Report: Study of the Effectiveness of Fire Service Positive Pressure Ventilation During Fire Attack in Single Family Homes Incorporating Modern Construction Practices

2016 ◽  
Author(s):  
Robin Zevotek ◽  
◽  
Steve Kerber
Keyword(s):  
Positive Pressure Ventilation ◽  
Fire Behavior ◽  
Fire Service ◽  
Scientific Data ◽  
Full Scale ◽  
Fuel Load ◽  
Positive Pressure ◽  
Research Report ◽  
Single Family ◽  
Fire Control

There is a continued tragic loss of firefighter and civilian lives, as shown by fire statistics. One significant contributing factor is the lack of understanding of fire behavior in residential structures resulting from the use of ventilation as a firefighter practice on the fire ground. The changing dynamics of residential fires as a result of the changes in home construction materials, contents, size and geometry over the past 30 years compounds our lack of understanding of the effects of ventilation on fire behavior. Positive Pressure Ventilation (PPV) fans were introduced as a technology to increase firefighter safety by controlling the ventilation. However, adequate scientific data is not available for PPV to be used without increasing the risk to firefighters. This fire research report details the experimental data from cold flow experiments, fuel load characterization experiments and full scale fire experiments. During the project it was identified that the positive pressure attack (PPA) and positive pressure ventilation (PPV) were often used interchangeably. For the purpose of this report they have been defined as PPA for when the fan is utilized prior to fire control and PPV for when the fan is used post fire control. The information from the full scale tests was reviewed with assistance from our technical panel of fire service experts to develop tactical considerations for the use of PPV fans in residential single family structures.

Study of the Effectiveness of Fire Service Positive Pressure Ventilation During Fire Attack in Single Family Homes Incorporating Modern Construction Practices

2016 ◽  
Author(s):  
Robin Zevotek ◽  
◽  
Steve Kerber
Keyword(s):  
Positive Pressure Ventilation ◽  
Fire Behavior ◽  
Fire Service ◽  
Scientific Data ◽  
Full Scale ◽  
Fuel Load ◽  
Positive Pressure ◽  
Research Report ◽  
Single Family ◽  
Fire Control

There is a continued tragic loss of firefighter and civilian lives, as shown by fire statistics. One significant contributing factor is the lack of understanding of fire behavior in residential structures resulting from the use of ventilation as a firefighter practice on the fire ground. The changing dynamics of residential fires as a result of the changes in home construction materials, contents, size and geometry over the past 30 years compounds our lack of understanding of the effects of ventilation on fire behavior. Positive Pressure Ventilation (PPV) fans were introduced as a technology to increase firefighter safety by controlling the ventilation. However, adequate scientific data is not available for PPV to be used without increasing the risk to firefighters. This fire research report details the experimental data from cold flow experiments, fuel load characterization experiments and full scale fire experiments. During the project it was identified that the positive pressure attack (PPA) and positive pressure ventilation (PPV) were often used interchangeably. For the purpose of this report they have been defined as PPA for when the fan is utilized prior to fire control and PPV for when the fan is used post fire control. The information from the full scale tests was reviewed with assistance from our technical panel of fire service experts to develop tactical considerations for the use of PPV fans in residential single family structures.

Effect of irrigation uniformity on evapotranspiration and onion yield

2010 ◽  
Vol 148 (2) ◽  
pp. 139-157 ◽  
Author(s):  
M. JIMÉNEZ ◽  
J. A. DE JUAN ◽  
J. M. TARJUELO ◽  
J. F. ORTEGA
Keyword(s):  
Water Deficit ◽  
Water Distribution ◽  
Irrigation System ◽  
Sprinkler Irrigation ◽  
Water Application ◽  
Crop Water ◽  
Water Requirements ◽  
Crop Water Requirements ◽  
The Impact ◽  
Experimental Plots

SUMMARYThe main objective of the current study was to analyse how water application through a sprinkler irrigation system influences yield of onion (Allium cepa L.), taking into account water application heterogeneity and the effects on theoretical crop evapotranspiration (ETc). Field experiments were conducted on commercial onion plots, irrigated with a permanent sprinkler irrigation system, located in Albacete, Spain, over two irrigation seasons. Two experimental plots were selected each study year: plot A (PA), in which water was applied heterogeneously by using sprinklers with different nozzle combinations, and plot B (PB, used as the reference plot) in which the four sprinklers were maintained with the same nozzle combinations. Both experimental plots were divided into 25 subplots with the aim of studying the water distribution (measured as Christiansen uniformity coefficient (CU)), the impact on the actual evapotranspiration (ETa) and the yield obtained. Irrigation was scheduled using a daily simplified water balance method within the root area following the approach of the Food and Agriculture Organization. In the present study, sprinkler irrigation in PA resulted in lower CU (65–82% lower in 2002 and 59–79% lower in 2005) compared with PB (78–92% lower in 2002 and 79–93% lower in 2005). Between 30 May and 18 August 2002, the estimated crop water requirements in PA in the absence of water deficit was 22 mm over the accumulated value of ETc (491 v. 469 mm), while estimated crop water requirements under water deficit were 187 mm below ETc (282 v. 469 mm). In 2005, between 29 May and 25 August, ETa without water deficit was more similar to ETc (458 v. 444 mm) but Eta under water deficit was 242 mm. The greater uniformity of water distribution in PB was translated into a greater uniformity of yield distribution. A smaller range in yield was observed in PB when compared with PA. No statistically significant differences were observed between PA and PB in the crop quality parameters bulb moisture content, total soluble solids, pH and total acidity.

scholarly journals Study of the Fire Service Training Environment: Safety, Fidelity, and Exposure -- Acquired Structures

2019 ◽  
Author(s):  
Keith Stakes ◽  
◽  
Joseph Willi
Keyword(s):  
Fire Service ◽  
Full Scale ◽  
Positive Pressure ◽  
Research Projects ◽  
Training Environment ◽  
Fuel Loads ◽  
Fire Environment ◽  
Service Training ◽  
Vertical Ventilation ◽  
The Impact

Previous FSRI led research projects have focused on examining the fire environment with regards to current building construction methods, synthetic fuel loading, and best-practices in firefighting strategies and tactics. More than 50 experiments have been previously conducted utilizing furniture to produce vent-limited fire conditions, replicating the residential fire environment, and studying the methods of horizontal ventilation, vertical ventilation, and positive pressure attack. Tactical considerations generated from the research are intended to provide fire departments with information to evaluate their standard operating procedures and make improvements, if necessary, to increase the safety and effectiveness of firefighting crews. Unfortunately, there still exists a long standing disconnect between live-fire training and the fireground as evident by continued line of duty injury and death investigations that point directly to a lack of realistic yet safe training, which highlights a continued misunderstanding of fire dynamics within structures. The main objective of the Study of the Fire Service Training Environment: Safety, Fidelity, and Exposure is to evaluate training methods and fuel packages in several different structures commonly used across the fire service to provide and highlight considerations to increase both safety and fidelity. This report is focused on the evaluation of live-fire training in acquired structures. A full scale structure was constructed using a similar floor plan as in the research projects for horizontal ventilation, vertical ventilation, and positive pressure attack to provide a comparison between the modern fire environment and the training ground. The structure was instrumented which allowed for the quantification of fire behavior, the impact of various ventilation tactics, and provided the ability to directly compare these experiments with the previous research. Twelve full scale fire experiments were conducted within the test structure using two common training fuel packages: 1) pallets, and 2) pallets and oriented strand board (OSB). To compare the training fuels to modern furnishings, the experiments conducted were designed to replicate both fire and ventilation location as well as event timing to the previous research. Horizontal ventilation, vertical ventilation, and positive pressure attack methods were tested, examining the proximity of the vent location to the fire (near vs. far). Each ventilation configuration in this series was tested twice with one of the two training fuel loads. The quantification of the differences between modern furnishings and wood-based training fuel loads and the impact of different ventilation tactics is documented through a detailed comparison to the tactical fireground considerations from the previous research studies. The experiments were compared to identify how the type of fuel used in acquired structures impacts the safety and fidelity of live-fire training. The comparisons in this report characterized initial fire growth, the propensity for the fire to become ventilation limited, the fires response to ventilation, and peak thermal exposure to students and instructors. Comparisons examined components of both functional and physical fidelity. Video footage was used to assess the visual cues, a component of the fire environment that is often difficult to replicate in training due to fuel load restrictions. The thermal environment within the structure was compared between fuel packages with regards to the potential tenability for both students and instructors.

Fire Service Summary Report: Study of the Effectiveness of Fire Service Vertical Ventilation and Suppression Tactics in Single Family Homes

2013 ◽  
Author(s):  
Steve Kerber ◽  
Keyword(s):  
Fire Behavior ◽  
Construction Materials ◽  
Fire Service ◽  
Fire Research ◽  
Single Family ◽  
Research Project ◽  
The Past ◽  
Home Construction ◽  
Vertical Ventilation ◽  
The Impact

There is a continued tragic loss of firefighter and civilian lives, as shown by fire statistics. One significant contributing factor is the lack of understanding of fire behavior in residential structures resulting from the use of ventilation as a firefighter practice on the fire ground. The changing dynamics of residential fires as a result of the changes in home construction materials, contents, size and geometry over the past 30 years compounds our lack of understanding of the effects of ventilation on fire behavior (Kerber S. , 2012). If used properly, ventilation improves visibility and reduces the chance of flashover or back draft. If a fire is not properly ventilated, it could result in an anticipated flashover, greatly reducing firefighter safety (Kerber S. , 2012). This fire research project developed empirical data from full-scale house fire experiments to examine vertical ventilation, suppression techniques and the resulting fire behavior. The purpose of this study was to improve firefighter knowledge of the effects of vertical ventilation and the impact of different suppression techniques. The experimental results may be used to develop tactical considerations outlining firefighting ventilation and suppression practices to reduce firefighter death and injury. This fire research project will further work from previous DHS AFG sponsored research (EMW-2008-FP-01774), which studied the impact of horizontal ventilation through doors and windows (Kerber S. , 2010).

scholarly journals Analysis of One and Two-Story Single Family Home Fire Dynamics and the Impact of Firefighter Horizontal Ventilation

2012 ◽  
Vol 49 (4) ◽  
pp. 857-889 ◽  
Author(s):  
Stephen Kerber
Keyword(s):  
Systems Approach ◽  
Fire Service ◽  
Experimental Investigations ◽  
Single Family ◽  
Fire Dynamics ◽  
Front Door ◽  
Open Floor ◽  
Modern House ◽  
The Impact ◽  
And Training

Abstract This paper describes experimental investigations on fire service ventilation practices in modern house geometries. Two houses were constructed inside a large fire facility. The first of two houses constructed was a one-story, 111.5 m2, 3 bedroom, 1 bathroom house with 8 total rooms. The second house was a two-story 297.3 m2, 4 bedroom, 2.5 bathroom house with 12 total rooms. The second house featured a modern open floor plan, two-story great room and open foyer. Fifteen experiments were conducted varying the ventilation locations and the number of ventilation openings. Ventilation scenarios included ventilating the front door only, opening the front door and a window near and remote from the seat of the fire, opening a window only and ventilating a higher opening in the two-story house. One scenario in each house was conducted in triplicate to examine repeatability. The results of these experiments examine potential occupant tenability and provide knowledge for the fire service for them to examine their horizontal ventilation standard operating procedures and training content. The fire dynamics resulting from ventilation practices such as ventilation near or remote from the seat of the fire and high versus low in relation to the fire are examined. Several other tactical considerations were developed utilizing the data from these experiments to provide specific examples of changes that can be adopted based on a departments current strategies and tactics. Such tactical considerations and a systems approach to fire service tactics should be investigated further.

Characteristics of Physician Relocation Following Hurricane Katrina

2009 ◽  
Vol 95 (1) ◽  
pp. 6-12
Author(s):  
Kusuma Madamala ◽  
Claudia R. Campbell ◽  
Edbert B. Hsu ◽  
Yu-Hsiang Hsieh ◽  
James James
Keyword(s):  
Hurricane Katrina ◽  
Gulf Coast ◽  
General Medicine ◽  
The United States ◽  
Lessons Learned ◽  
Bivariate Analysis ◽  
Fisher Exact Test ◽  
Exact Test ◽  
Factors Associated ◽  
The Impact

ABSTRACT Introduction: On Aug. 29, 2005, Hurricane Katrina made landfall along the Gulf Coast of the United States, resulting in the evacuation of more than 1.5 million people, including nearly 6000 physicians. This article examines the relocation patterns of physicians following the storm, determines the impact that the disaster had on their lives and practices, and identifies lessons learned. Methods: An Internet-based survey was conducted among licensed physicians reporting addresses within Federal Emergency Management Agency-designated disaster zones in Louisiana and Mississippi. Descriptive data analysis was used to describe respondent characteristics. Multivariate logistic regression was performed to identify the factors associated with physician nonreturn to original practice. For those remaining relocated out of state, bivariate analysis with x2 or Fisher exact test was used to determine factors associated with plans to return to original practice. Results: A total of 312 eligible responses were collected. Among disaster zone respondents, 85.6 percent lived in Louisiana and 14.4 percent resided in Mississippi before the hurricane struck. By spring 2006, 75.6 percent (n = 236) of the respondents had returned to their original homes, whereas 24.4 percent (n = 76) remained displaced. Factors associated with nonreturn to original employment included family or general medicine practice (OR 0.42, 95 percent CI 0.17–1.04; P = .059) and severe or complete damage to the workplace (OR 0.24, 95 percent CI 0.13–0.42; P < .001). Conclusions: A sizeable proportion of physicians remain displaced after Hurricane Katrina, along with a lasting decrease in the number of physicians serving in the areas affected by the disaster. Programs designed to address identified physician needs in the aftermath of the storm may give confidence to displaced physicians to return.

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