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A series of six experiments was conducted in a highrise apartment building in Chicago, Illinois. One experiment on each of the fire floors utilized portable fans and the other utilized a large truck or trailer mounted fan. The two experiments on the third floor examined the effects of wind driven fire conditions. All of the experiments created high temperatures and dense smoke conditions in the hallway. Numerous configurations were used during the experiments and the ability of the fans to keep smoke and heat out of the stairwell was analyzed. The minimum design pressures of NFPA 92A were used as baselines to compare to the actual pressures measured.In this limited set of experiments portable fans and mounted fans were able to quickly clear the stairwell of smoke and maintain a pressure high enough to prevent smoke infiltration into the stairwell. Positive pressure ventilation fans utilized correctly can increase the effectiveness and safety of fire fighters and survivability of occupants in high-rise buildings. When configured properly PPV fans can meet or exceed previously established performance metrics for fixed smoke control systems.
Fire departments use ventilation blowers or fans to pressurize a structure prior to suppressing a fire. This pressurization or positive pressure ventilation (PPV) tactic has not been characterized carefully enough to establish specific guidelines for optimum use of PPV. PPV can assist in the venting of smoke and high temperature combustion products and make attacking the fire easier than without PPV. However, this tactic also provides additional oxygen to the fire and can increase the rate of heat and energy being released. This study examined gas temperatures, gas velocities and total heat release rate in a series of fires in a furnished room. The use of the PPV fan created slightly lower gas temperatures in the fire room and significantly lower gas temperatures in the adjacent corridor. The gas velocities at the window plane were much higher in the PPV case than in the naturally ventilated scenario. This higher velocity improved visibility significantly. PPV caused an increase in heat release rate for 200 s following initiation of ventilation but the heat release rate then declined at a faster rate than that of the naturally ventilated experiment.
The purpose of this document is to provide the foundation for the development of a guidance document on emergency communication message content and dissemination strategies. The document answers three major questions regarding emergency communication systems: 1) What technology exists or is proposed for use in emergency notification? 2) What approaches are currently being used to disseminate messages? 3) How does the public respond to different types of information and information sources? The document begins with a discussion of the technology that exists or is proposed for use in emergency notification, along with the positive and negative aspects of each system. The ways in which social media tools can be used to provide warnings in emergencies are included. Second, the document discusses the various types of emergencies for which warnings are needed, the range of protective actions that are taken by building occupants in emergencies, and the nature of the information required based upon the emergency type. The emergency communication systems installed in two different college campuses are described as examples of approaches used to disseminate warnings during emergencies. Finally, a comprehensive literature review is presented on how the public responds to various types of information and information sources both in emergency and non-emergency conditions. A summary list of the relevant findings from each literature source is assembled in Appendix A to identify the most effective ways to create or disseminate messages to achieve optimal occupant response. Detailed annotations for each source are presented in Appendix B.
The U.S. Consumer Product Safety Commission (CPSC) initiated a program to determine the effects of emissions from problem drywall on residential electrical, gas distribution, and fire safety components. As part of this program, the National Institute of Standards and Technology (NIST) generated data to help determine whether there has been degradation in the activation performance of automatic residential fire sprinklers exposed to those emissions, as manifested by changes to sprinkler activation time. NIST tested three sets of sprinklers in the sensitivity test oven (plunge test apparatus), according to the oven heat test section of UL 199 / UL 1626. Set 1 (bulb type) residential sprinklers were provided by CPSC staff and described as having been installed in homes with problem drywall; Set 2 sprinklers (bulb and fusible types) were purchased new by NIST and tested as received; and Set 3 comprised new sprinklers, of the same models as Set 2, after they had been subjected to an accelerated aging protocol, the Battelle Class IV corrosivity environment. Sprinklers from all three sets were installed and tested in the UL 199 / UL 1626 plunge test apparatus.
The National Institute of Standards and Technology (NIST) received funding through the American Recovery and Reinvestment Act (ARRA) to construct a Net Zero Energy Residential Test Facility (NZERTF). The initial goal of the NZERTF is to demonstrate that a net-zero energy residential design can "look and feel" like a typical home in the Gaithersburg area. Demonstration phase of the project intends to demonstrate that the operation of the house does perform at "net zero," or produces as much electricity as it consumes over an entire year. The NZERTF is scheduled to begin the demonstration phase in 2013. The purpose of this report is to create a whole building energy simulation that will replicate the NZERTF design to estimate its energy performance, both in aggregate as well as at the individual occupant and equipment level.
Defines the content, format, and units of measurement for the exchange of fingerprint, palmprint, facial/mugshot, and scar, mark, & tattoo (SMT) image information that may be used in the identification process of a subject. The information consists of a variety of mandatory and optional items, including scanning parameters, related descriptive and record data, digitized fingerprint information and compressed or uncompressed images. This information is intended for interchange among criminal justice administrations or organizations that rely on automated fingerprint (AFIS) and palmprint identification systems or use facial or SMT data for identification purposes.
Although there is a great deal of high-quality information available on resilience-related topics hazard assessment, vulnerability assessment, risk assessment, risk management, and loss estimation as well as disaster resilience itself, there is no central source of data and tools to which the owners and managers of constructed facilities, community planners, policy makers, and other decision makers can turn for help in defining and measuring the resilience of their structures and communities. The purpose of this document is to provide a survey of the literature and an annotated bibliography of printed and electronic resources that serves as that central source of data and tools to help readers develop methodologies for defining and measuring the disaster resilience of their structures and communities. The report covers resilience-related topics at two different levels: (1) individual constructed facilities and correlated collections of constructed facilities that form a network (e.g., hospitals) and (2) community/regional scale frameworks (e.g., physical infrastructure, business and economic relationships, population and employment demographics). Thus, the first level focuses on physical infrastructure, whereas the second takes a broader look at how the physical infrastructure interacts with other activities that collectively define modern communities. The reason for taking this approach is to establish a foundation for developing methodologies for defining and measuring the disaster resilience of structures. This step is especially important because physical infrastructure enables the community to function as a place of employment, a window to the regional and national economy, and a home for individuals. Developing better metrics and tools for defining and measuring the resilience of structures is an important step in meeting the challenge of measuring disaster resilience at the community scale.
This paper reports an experimental technique that is developed for instantaneous planar measurement of droplet size and velocity for dilute sprays in general and sprinkler sprays in particular. This particle tracking technique relies on photographic measurements of two-color fluorescence or fluorescence and Mie scattering from droplets to determine their size and velocity. Measurements were made in a plane that passes through the vertical axis of symmetry of an axis-symmetric sprinkler spray. Drop velocities and drop sizes down to 200 m were measured from the digitized double-exposed photographs of sprinkler sprays. The directional ambiguity was resolved by color differentiation. A combination of fluorescence and Mie scattering was investigated for a 250 mm x 350 mm measurement area, while two-color fluorescence was investigated for 460 mm x 540 mm measurement area. Dye selection and concentrations were determined by testing the fluorescence output of various water tracer dyes. Collection optics and laser powers were varied to optimize the color differentiation and maximize the resolution for drop size measurements.
The NRC Resident Research Associateship Program at NIST provides two-year temporary appointments for outstanding scientists and engineers. This book describes program applicants and awardees and offers suggestions for an in-depth assessment of career outcomes. Preliminary investigation indicates that outreach efforts produce more qualified applicants than NIST has slots to fill, the pool of applicants is increasingly diverse, and many Research Associates go on to permanent positions at NIST. The agency should conduct a more thorough evaluation of the program, including an assessment of outreach to potential applicants, individuals who decline an award, the program's impact on the careers of awardees, and the benefits of the program to NIST and the broader scientific and engineering community. Table of Contents Front Matter Executive Summary 1 Overview 2 Recruitment and Selection 3 Research Associates' Experiences 4 Careers 5 Preliminary Results and Recommendations Bibliography Appendix A Committee Members Biographical Information Appendix B Survey of Earned Doctorates Appendix C Data on Science and Engineering Doctorates Appendix D Application for Research Associate Programs Appendix E Examination of Applications to Prospective Programs Appendix F Ph.D. Fields by Broad Category Appendix G Names of Laboratories Appendix H Research Associateship Final Report Appendix I Evaluation of Associate by Adviser
A review is presented of the state of the art of smoke production measurement, prediction of smoke impact as part of computer-based fire modeling, and measurement and prediction of the impact of smoke through deposition of soot on and corrosion of electrical equipment. The literature review on smoke corrosivity testing and damage due to smoke deposition emphasizes (despite extensive research on smoke corrositity) the lack of validated and widely applicable prescriptive or performance based methods to assure electrical equipment survivability given exposure to fire smoke. Circuit bridging via current leakage through deposited smoke was identified as an important mechanism of electronic and electrical equipment failure during NPP fires. In the near term, assessment of potential damage can reasonably be based on the airborne smoke exposure concentration and, perhaps, the exposure duration. Hence, models that can predict the airborne smoke concentration would be sufficient to suit short-term analysis needs. In the longer term, it would be desirable to develop models that could estimate the deposition behavior of smoke, as well and specifically correlate the combination of deposited and airborne smoke to component damage.
Bulk oxide determinations from a pair of portland cements provides the basis for calculation precision and accuracy values for X-ray fluorescence (XRF) analysis for both the fused glass bead and the pressed powder sample preparation. Approximately 45 laboratories provided six replicates analyzed in duplicate for two separate portland cements covering eleven analytes, CaO, SiO2, Al2O3, Fe2O3, SO3, MgO, Na2O, K2O, TiO2, P2O5, and Cl, with the laboratories roughly split between the two different sample preparations. Chemical data using traditional chemical analyses (the Reference Methods) from the Cement and Concrete Reference Laboratory (CCRL) proficiency test program were included for comparison to the XRF results.
Research funded under the Fire Safe Cigarette Act of 1990 (P.L. 101-352) has led to the development of two test methods for measuring the ignition propensity of cigarettes. The Mock-Up Ignition Test Method uses substrated physically similar to upholstered furniture and mattresses: a layer of fabric over padding. The measure of cigarette performance is ignition or non-ignition of the substrate. The Cigarette Extinction Test Method replaces the fabric/padding assembly with multiple layers of common filter paper. The measure of performance is full-length burning or self-extinguishment of the cigarette. Routine measurement of the relative ignition propensity of cigarettes is feasible using either of the two methods. Improved cigarette performance under both methods has been linked with reduced real-world ignition behavior; and it is reasonable to assume that this, in turn, implies a significant real-world benefit. Both methods have been subjected to interlaboratory study. The resulting reproducibilities were comparable to each other and comparable to those in other fire test methods currently being used to regulate materials which may be involved in unwanted fires. Using the two methods, some current commercial cigarettes are shown to have reduced ignition propensities relative to the current best-selling cigarettes. *] This is one of six volumes in the Final Report, Fire Safe Cigarette Act of 1990. VOLUME 1. Overview: Practicability of Developing a Performance Standard to Reduce Cigarette Ignition Propensity by Jones-Smith, J., et al. VOLUME 3. Modeling the Ignition of Soft Furnishings by a Cigarette by Mitler, H. E., et al. VOLUME 4. Cigarette Fire Incident Study by Harwood, B., et al. VOLUME 5. Toxicity Testing Plan by Lee, B. C., et al. VOLUME 6. Societal Costs of Cigarette Fires by Ray, D. R., et al.
FAST is a collection of fire modeling tools which uses the underlying fire model CFAST and adds the routines of FIREFORM to provide engineering calculations of fire phenomena in compartmented structures. This manual provides documentation and examples for using FAST. It describes how to install the software on a computer and provides a guide for the use of FAST using examples.
The National Institute of Standards and Technology hosted a twoday workshop focusing on needed research on occupant behavior and movement during building emergencies. This workshop was motivated by a renewed interest in how buildings should be evacuated during fire emergencies and by the desire to provide a forum for the exchange of experiences among the fire and non-fire communities working on emergency egress. The workshop was organized into several sessions with specific topics areas, including codes and standards requirements for building evacuation, building egress strategies, and data needs for predictive models. Several presentations were included in each session, with an extended period for discussion at the end of each session. For each presentation, visuals used for the presentation are included, along with any additional information provided by the author on the topic. For each workshop session, the session moderator prepared a summary of key points of research interest from the presentations and discussion.
New technologies and research are redefining the state-of-the-art in building evacuation. The time is right to rethink the entire infrastructure of egress from buildings in light new opportunities to address the economic and life-safety issues. Approximately 40 experts from a variety of disciplinary background assembled in Warrenton, VA from April 1-3, 2008 in order to consider building evacuation, starting with a blank sheet of paper. Structured around the principles of Value-Focused Thinking (a text authored by workshop moderator Ralph Keeney), the participants were encouraged to consider values, objectives, alternatives, and metrics. This process combined the benefits of free-thinking brainstorming with a formalism which encouraged evaluation of the potential for new ideas. By the conclusion of the third day, over 400 ideas had been developed, along with metrics for future evaluation of the ideas.
Fire protection measures are needed to maintain the safety and integrity of the Nation s building stock and to limit loss of life and property when building fires do occur. Statistics published by the National Fire Protection Association demonstrate that fire protection is a major investment cost in building construction. Therefore, ways to reduce these costs while ensuring safety are of interest to building owners, fire protection engineers, and other construction industry stakeholders. Although all fire protection measures have important economic implications, the focus of this report is on egress-related requirements in new building construction. Recent changes in the International Building Code have set the stage for analyzing the costs of several key egress-related requirements. The U.S. General Services Administration commissioned this study to conduct an economic analysis of the use of elevators and exit stairs for occupant evacuation and fire service access. The goal of this study is to produce analyses of cost data suitable for evaluating improved egress system designs that promote efficient and timely egress of occupants, including those with disabilities, and that facilitate more efficient fire department operations. This report tabulates cost data for selected egress-related requirements in five prototypical buildings. The five prototypical buildings range in height from a 5-floor, mid-rise building to a 75- floor, high-rise building. Cost data are tabulated in a format that facilitates lifecycle cost analyses of selected egress-related requirements. Incremental costs are also tabulated to help assess the implications of changing one or more design parameters. The results of the economic analysis for four prototypical buildings over 120 ft (37 m), with two over 420 ft (128 m) high, demonstrate that: (1) an additional exit stair is a cost-effective alternative to the installation of occupant evacuation elevators on a first-cost basis; and (
Whole-building airflow and contaminant transport modeling has a potentially important role in the development of contaminant sampling strategies in response to the airborne release of chemical or biological agents . The effectiveness of these strategies relies on the ability of the selected sampling locations to adequately characterize the levels of contamination throughout an exposed facility to a desired level of confidence in the sampled results. The Department of Homeland Security has sponsored a series of multi-agency exercises, during which contamination experiments were performed to gauge the confidence that could be obtained by various sampling strategies as well as the effectiveness of various sampling methods in a real-world setting. These experiments are very resource intensive and time-consuming, limiting the number of experiments that can be reasonably performed. Building simulation can be used to perform virtual experiments that would allow more tests to be performed under a much larger set of building operational and environmental configurations. However, in order for the simulations to be useful, the building models need to provide realistic results with a high level of confidence. The purpose of this report is to describe a simulation validation effort based on measurements of contaminant levels performed during the aforementioned exercises.
This report presents a computational assessment of the performance of steel gravity framing systems with single-plate shear (, shear tab ) connections and composite floor slabs under column loss scenarios. The computational assessment uses a reduced modeling approach, while comparisons with detailed model results and available experimental data are presented to establish confidence in the reduced models. The reduced modeling approach enables large multi-bay systems to be analyzed much more efficiently than the detailed modeling approaches used in previous studies. Both quasi-static and sudden column loss scenarios are considered, and an energy-based approximate procedure for analysis of sudden column loss is adopted, after verification through comparisons with direct dynamic analyses, further enhancing the efficiency of the reduced modeling approach. Reduced models are used to investigate the influence of factors such as bay spacing, slab continuity, and the mode of connection failure on the collapse resistance of gravity frame systems. Simple equations for the rotational capacities of the connections are derived as a function of a few parameters including the span length and the connection depth. These equations yield good agreement with computed rotational capacities of connections both in bare steel assemblies (i.e., no slab) and in composite floor systems, where composite action leads to reduced rotational capacities. The reduced models are used to assess the adequacy of current structural integrity requirements, and based on the computational results, a new relationship is proposed between the uniform load intensity and the tie forces required for collapse prevention
A standard procedure is needed for obtaining smoke toxic potency data for use in fire hazard and risk analyses. Room fire testing of finished products is impractical, directing attention to the use of apparatus that can obtain the needed data quickly and at affordable cost. This report examines the first of a series bench-scale fire tests to produce data on the yields of toxic products in both pre-flashover and post-flashover flaming fires. The apparatus is the radiant furnace in NFPA 269 and ASTM E 1678. Test specimens were cut from finished products that were also burned in room-scale tests: a sofa made of upholstered cushions on a steel frame, particleboard bookcases with a laminated finish, and household electric power cable. Initially, the standard test procedure was followed, with a variation to reduce the contribution to the effluent of post- flaming pyrolysis. Subsequent variations in the procedure included cutting the test specimen into small pieces and performing the tests at a reduced oxygen volume fraction of 0.17. The yields of CO2 CO, HCl, and HCN were determined. The yields of other toxicants (NO, NO2, formaldehyde, and acrolein) were below the detection limits, but volume fractions at the detection limits were shown to be of limited toxicological importance relative to the detected toxicants. In general, dicing the test specimen and performing the tests at the reduced oxygen volume fraction had little effect on the toxic gas yields, within the experimental uncertainties. The exceptions were an increase in the CO yield for diced specimens at reduced oxygen, a decrease in the HCN yield from the intact sofa and cable specimens at reduced oxygen, and an increase in the HCN yield from dicing the cable specimens. In none of the procedure variations did the CO yield approach the value of 0.2 found in real-scale post flashover fire tests.
A standard procedure is needed for obtaining smoke toxic potency data for use in fire hazard and risk analyses. Room fire testing of finished products is impractical, directing attention to the use of apparatus that can obtain the needed data quickly and at affordable cost. This report presents examination of the second of a series bench-scale fire tests to produce data on the yields of toxic products in both pre-flashover and post-flashover flaming fires. The apparatus is the ISO/TS 19700 controlled equivalence ratio tube furnace. This apparatus uses a mechanical feed mechanism to supply solid fuel into a tube furnace at a pre-determined rate, so that the global equivalence ratio can be adjusted. The test specimens were cut from finished products that were also burned in room-scale tests: a sofa made of upholstered cushions on a steel frame, particleboard bookcases with a laminated finish, and household electric cable. Initially, the standard test procedure was followed for two fire stages, well ventilated flaming and post- flashover. Subsequent variation in the procedure included dicing the specimen, further decreasing the equivalence ratio (well ventilated flaming) or increasing it (post-flashover), increasing the mass loading while maintaining the equivalence ratio, and increasing the fuel feed rate while maintaining the equivalence ratio. The yields of CO2 CO, HCl, and HCN were determined. The yields of other toxicants (NO, NO2, formaldehyde, and acrolein) were below the detection limits, but volume fractions at the detection limits were shown to be of limited toxicological importance relative to the detected toxicants. In general, the largest effects were seen between the two fire stages. The other variations within the fire stage had minor effects on gas yields. Under post-flashover conditions, the sum of the CO2 and CO yields frequently accounted for half or less of the carbon originally in the specimen. As a result, the gaseous combustion products cannot be used to estimate the mass burning rate. Under post flashover conditions, the CO yield for the sofa approached the value of 0.2 found in real-scale postflashover fire tests. However, for the bookcase and cable it did not. Yields of HCl from the cables generally approached their notional yields under well- ventilated conditions, and HCN was most readily detected from the sofa under post-flashover conditions at toxicologically significant concentrations.
This study examines the energy consumption of automatic ice makers installed in domestic refrigerators. This study builds upon the findings of a previous study and examines two refrigerator-freezers of different configurations, one French-door units with bottom freezers and one bottom mount unit that uses a twist tray mechanism to free frozen ice from the icemaker. Ice maker energy consumption is difficult to measure because they operate on a periodic cycle which is independent of the compressor cycle used to maintain the cold temperatures in the domestic refrigerator where it is installed; therefore methods proposed prior to this study have been subject to significant truncation error due to partial ice maker or compressor cycling. The purpose of this study is to define a method of measuring the energy consumption of automatic ice makers that will generate a repeatable and reproducible result. Several sets of test data from these units were analyzed and used to decipher the energy consumption of automatic ice makers. Through this effort, we developed a method of test to characterize ice maker energy consumption which circumvents the inherent problem with its measurement, truncation error due to incomplete cycling. The truncation error is avoided by measuring specific parameters with different sections of data from the same data set. This method was found to rapidly approach steady state values for the ice maker energy consumption. We then analyzed data sets from a prior study and found similar results for the stability of the ice making energy consumption; that continuous data over only 6 or 7 ice making cycles are typically sufficient to accurately characterize the energy consumption.
We analyze data from NIST field tests in which radio-propagation channel path loss values were measured at approximately the same physical locations where the performance of various RF-based firefighter distress beacons were tested. These side-by-side tests were made in two key representative emergency responder environments, a New York subway station and the Empire State Building. These environments contain propagation features that may impair radio communications, including stairwells, tunnels, and rooms deep within buildings, among others. The goal of this work is to determine appropriate performance metrics for use in the development of laboratory-based test methods for RF-based electronic safety equipment. The analysis supports the classification of structures into categories of attenuation values that can be used in laboratory-based test methods to verify the performance of the RF-based alarm systems. The environments, tests, and measured data are discussed in detail. The RF propagation-channel data also provide insight into the expected attenuation in high-rise buildings and below-ground structures.
A standard procedure is needed for obtaining smoke toxic potency data for use in fire hazard and risk analyses. Room fire testing of finished products is impractical, directing attention to the use of apparatus that can obtain the needed data quickly and at affordable cost. In this work we compare yields of toxic gases generated by four bench scale apparatus to previously conducted room-scale fires. The bench scale apparatus are the radiant apparatus in NFPA 269 and ASTM E 1678, the smoke density chamber in ISO 5659-2, a controlled-atmosphere version of the cone calorimeter (ASTM E 1354), and the tube furnace in ISO/TS 19700. In the bench scale experiments, the test specimens were cut from finished products that were also burned in the room-scale tests: a sofa made of upholstered cushions on a steel frame, particleboard bookcases with a laminated finish, and household electric cable. The yields of CO2 CO, HCl, and HCN were determined. The yields of other toxicants (NO, NO2, formaldehyde, and acrolein) were below the detection limits, but volume fractions at the detection limits were shown to be of limited toxicological importance relative to the detected toxicants. The bench scale and room scale yields are compared, and the bench scale apparatus are assessed for the degree to which they accurately predict room scale yields. The results of this study provide a better basis for obtaining toxic potency input data for fire modeling than currently exists.
The National Institute of Standards and Technology's Manufacturing Engineering Laboratory (MEL)strengthens the U.S. economy and improves the quality of life by working with the U.S. manufacturing industry to develop and apply infrastructural technology, measurements, and standards to meet their needs. This report contains summaries of MEL programs that support the needs of the U.S. manufacturing industry. Each program summarizes the resources, objectives, customer needs that are addressed, accomplishments, current year plans, lifetime objectives, and related measurement and standards work.
Economic tools are needed to help the owners, managers, and designers of constructed facilities to select cost-effective combinations of mitigation strategies that respond to natural and man-made hazards. Economic tools include evaluation methods, standards that support and guide the application of those methods, and software for implementing the evaluation methods. Developing a cost-effective risk mitigation plan involves assessing the risks associated with natural and man-made hazards, formulating combinations of mitigation strategies for constructed facilities exposed to those hazards, and using economic tools to identify the most cost-effective combination of strategies. Developing a risk mitigation plan requires both guidance and data. Guidance is needed to help owners and managers to assess the risks facing their facility. Data about the frequency and consequences of natural and man-made hazards are needed when assessing the risks that a particular facility faces from these hazards. Estimates of the costs of protection are needed to insure that safeguarding personnel and physical assets and satisfying financial constraints are kept in balance. Although there is a great deal of high-quality information available on risk assessment and risk management, natural and man-made hazards, and economic tools, there is no central source of data and tools to which the owners and managers of constructed facilities and other key decision makers can turn for help in developing a cost-effective risk mitigation plan. This document provides an annotated bibliography of printed and electronic resources that serves as a central source of data and tools to help the owners, managers, and designers of constructed facilities develop a cost effective risk mitigation plan. |
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