Welcome to Loot.co.za!
Sign in / Register |Wishlists & Gift Vouchers |Help | Advanced search
|
Your cart is empty |
|||
Showing 1 - 25 of 213 matches in All Departments
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.
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 (
There is a general concern that the US manufacturing industry has lost competitiveness with other nations. Additive manufacturing may provide an important opportunity for advancing US manufacturing while maintaining and advancing US innovation. Additive manufacturing is a relatively new process where material is joined together layer by layer to make objects from 3D models as opposed to conventional methods where material is removed. The US is currently the primary user of additive manufacturing technology and the primary producer of additive manufacturing systems. Globally, an estimated $642.6 million in revenue was collected for additive manufactured goods with the US accounting for an estimated $468.9 million or 72.9% of global production in 2011. Change agents for the additive manufacturing industry can focus their efforts on three primary areas to advance this technology: cost reduction, accelerating the realization of benefits, and increasing the benefits of additive manufacturing. Significant impact on these areas may be achieved through the reduction in the cost of additive manufacturing system utilization, material costs, and facilitating the production of large products. There is also a need for a standardized model for cost categorization and product quality and reliability testing.
This study demonstrates the performance improvement of an air-to-air roof top unit (RTU) achieved by optimizing an evaporator s refrigerant circuitry using evolutionary algorithms. The subject of this study is a unit with a cooling capacity of 7.5 Tons (26.4 kW). The RTU employs two separate refrigerant cycles having separate compressors, condensers, and thermostatic expansion valves (TXV) but using a single evaporator slab in which two separate refrigerant circuits are implemented. We modified the RTU by replacing the refrigerant-to-air condensers with water cooled brazed plate heat exchangers in order to facilitate testing. Performance tests were conducted in a conditioned environmental chamber in line with AHRI standard 340/360; in order to accomplish this, we maintained the liquid line saturation pressure and subcooling from the manufacturer s test data by adjusting the condenser water flow rate and temperature. We also measured the in-situ air velocity profile using Particle Image Velocimetry (PIV), a non-intrusive, laser-based technique. The measurements showed that the range of air velocities passing through the heat exchanger varied from 0.5 ms-1 to 3.0 ms-1, with the integrated average of the measurements being 1.75 ms-1. The PIV data was used to generate a map of the air flow distribution through the heat exchanger, which served as the basis for refrigerant circuitry optimization.
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.
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.
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.
Due to concerns about potential airborne chemical and biological (chembio) releases in or near buildings, building owners and managers and other decision makers are considering retrofitting buildings to provide some degree of protection against such events. A wide range of technologies and approaches are being proposed with varying levels of efficacy and cost, as well as varying degrees of applicability to particular buildings and ventilation systems. This document presents the results of an effort to evaluate chembio retrofit options for buildings. A number of retrofit options are identified, and their potential to protect building occupants from a number of generic contaminant releases is evaluated using building airflow and contaminant transport modeling. In addition, a case study is presented in which specific retrofit options were considered for two actual buildings and pre-installation designs and cost estimates were developed. Based on the analyses performed, the results of the case study and other available information, guidance on the application and effectiveness of various retrofits are presented. An economic analysis software tool employing life cycle cost analysis techniques was developed as part of this project, and its use is described in an appendix to this report. The retrofit options considered fall into two categories, the first being stand-alone technologies or devices such as enhanced particulate filtration that are installed and implemented as purchased. The second category includes retrofit approaches that employ operational strategies or building modifications to increase building protection, such as outdoor air purging or building envelope tightening. The guidance section describes each retrofit technology and approach in some detail, presenting relevant performance data and the level of protection that might be expected from the retrofit. Potential disadvantages and knowledge gaps are also discussed for each technology. The retrofit technologies considered include enhanced particle filtration, sorbent based gaseous air cleaning, ultraviolet germicidal irradiation, photocatalytic oxidative air cleaning, and work area air capture and filtration equipment such as mail handling tables. The approaches include ventilation system recommissioning, building envelope tightening, building pressurization, relocation of outdoor air intakes, shelter-in-place (SIP), isolation of vulnerable spaces such as lobbies, system shutdown and purge cycles, and automated HVAC operational changes in response to contaminant sensing. The filtration and air cleaning options are noted to have an advantage of always being operational, which is an advantage as long as the systems are properly designed, installed and maintained. However, the lack of standard test methods for sorbent-based gaseous air cleaning and other air cleaning approaches is identified as a critical impediment to the application of these technologies. Building envelope air sealing and pressurization can be quite effective in protecting against outdoor releases as long as effective filtration against the contaminant of concern is also in place. The protection provided by operational changes such as system shutdown and purging are shown to be very dependent on the timing of their implementation, with the possibility of increasing occupant exposure if the timing is inappropriate. Isolating vulnerable zones and other system related modifications are highly dependent on the building layout and system design, and their implementation must be well conceived to be effective under the range of conditions that exist in buildings. Finally, many retrofits are noted as also providing additional benefits of increased energy efficiency and improved indoor air quality, which need to be included in the life-cycle cost comparison of different options to the degree possible.
The Homeland Security Presidential Directive HSPD-12 called for new standards to be adopted governing the interoperable use of identity credentials to allow physical and logical access to Federal government locations and systems. The Personal Identity Verification (PIV) for Federal Employees and Contractors, (Federal Information Processing Standard 201 (FIPS 201)) was developed to establish standards for identity credentials. This document, Special Publication 800-87 (SP 800-87), provides the organizational codes necessary to establish the PIV Federal Agency Smart Credential Number (PIV FASC-N) that is required to be included in the FIPS 201 Card Holder Unique Identifier (CHUID) and is a companion document to FIPS 201.
The purpose of this workshop was to identify performance needs and establish research priorities to address the thermal characteristics of respiratory equipment used by emergency first responders. The workshop provided a forum for representatives from the first responder community, self contained breathing apparatus (SCBA) and component manufacturers, and research and testing experts to discuss issues, technologies, and research associated with SCBA high temperature performance. The goals of the workshop were defined in two parts: 1) Clarify baseline information, including the current state-of-the-art, applicable fire service events, and current related research, and 2) Research planning, including identification of performance needs and short and long term research priorities. Presentations were given to explain the current SCBA and certification process, understand experience from actual fire service incidents, and review the current state of respirator research. After the presentations, the workshop divided into three working group sessions to discuss performance needs and research priorities in smaller groups. Suggested topics for discussion included: a) Current Equipment, b) Current Practice and Usage, c) Future Trends, d) Short Term Research Needs, e) Long Term Research Needs, and f) other issues. The results of the three smaller groups' deliberations were discussed when the full workshop reconvened. The responses from each group were merged into a combination of issues that related to the use and performance of the lens of the SCBA. The primary concerns and research priorities were the characterization of the fire fighter environment, performance of current and new technology, development of representative and realistic testing, and improvements to fire fighter training on the limitations of protective equipment. A significant amount of discussion concentrated on the testing for NFPA certification, which currently contains limited thermal testing.
Things a Woman Should be Doing Outside of the Kitchen is a 114 page book that is completely blank inside. Every page is intentionally left blank and even the words "This page intentionally left blank" don't appear. The pages are lined so the book can be used as a notebook. This book is intended for humorous discussions.
This paper presents the findings of a study conducted to measure the impact of JPEG 2000 compression on fingerprint imagery at various levels of compression. The impact of compression is measured in terms of impact to both Galton and non-Galton based features of a fingerprint by utilizing the professional judgment of trained and seasoned fingerprint examiners. This impact is analyzed by consolidating and quantifying multiple decisions and associating a cost with the different levels of image compression loss incurred during compression. In addition to measuring the perceived visual impact of compression on the aforementioned features of the fingerprint as a result of compression, this paper also examines the impact of compression on the examiner's ability to render identification decisions.
Safety in the patient compartment of ambulances is an issue of growing concern for emergency medical technicians (EMTs), paramedics, patients, and others affected by ambulances. A lot of research has been conducted by different players and much of it is scattered. As a quick reference, this report is to enhance the ability of researchers of this field to sift through a collection of standards and documents from books, journals, websites, and reports. This annotated bibliography is categorized into different fields for further ease of use. A brief abstract follows every bibliographical reference. |
You may like...
The Entomologist's Record and Journal of…
James William 1858-1911 Tutt
Hardcover
R980
Discovery Miles 9 800
Considerations of Territorial Planning…
Helmuth Yesid Arias Gomez, Gabriela Antosova
Hardcover
R6,552
Discovery Miles 65 520
Handbook on Space, Place and Law
Robyn Bartel, Jennifer Carter
Paperback
R1,380
Discovery Miles 13 800
Introduction to the Air Transport System
Milica Kalic, Slavica Dozic, …
Hardcover
R4,281
Discovery Miles 42 810
|