摘要 :
A real-scale fire test rig has been used to study the flammability of LAN communication cables installed horizontally in concealed spaces in buildings as part of a wider "Partners in Technology"(PIT) study. The scenario addressed ...
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A real-scale fire test rig has been used to study the flammability of LAN communication cables installed horizontally in concealed spaces in buildings as part of a wider "Partners in Technology"(PIT) study. The scenario addressed was of an office fire of IMW, 45 minutes duration, below a plenum space containing the cables for study. Heating, Ventilating and Air Conditioning (HVAC) in the plenum could be simulated by a fan and duct system and the rig was comprehensively instrumented to measure temperatures, heat release, smoke density and flows, pressure differentials and combustion gases. Sophisticated video and infra red imaging techniques were employed. Major conclusions from the PIT study are that (i) current installation practices are resulting in increasingly high volumes of many generations of cables in concealed spaces (providing a high fire load), (ii) turning off the HVAC system to prevent transmission of fire and fire products around a building can result in potentially explosive events in the oxygen depleted voids, (iii) cable formulations which "pass" vertical sample Standard tests may burn readily in a real-scenario horizontal orientation. (iv) small-scale reaction-to-fire tests may not fully predict real scale performance.
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Changing environmental interests and new fire safety performance concerns in the wire and cable industry (WCI) have generated studies into the fire hazard and eco-performance of various data and communication cabling system altern...
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Changing environmental interests and new fire safety performance concerns in the wire and cable industry (WCI) have generated studies into the fire hazard and eco-performance of various data and communication cabling system alternatives for computers and local area networks (LAN). To accurately assess the various alternatives, the installed electronic functionality and fire safety performance requirements of the various end-use product options must be equivalent. For high fire performance communication cables (HFP-cables), many existing local and national regulations differentiate between end product performance options and building fire protection needs. High fire-performance, high societal-value based PVC sheathed and perfluoropolymer (PFP) insulated (PVC/PFP) cables can be routed directly in concealed plenum spaces in buildings, while products that do not meet specific high fire performance criteria, such as low-smoke zero-halogen (LSZH/PE) cables or riser-rated cables (CMR or PVC/PE), often must be protected inside other structures that do meet these building fire standards, typically using steel conduit or trunking. However, some low fire performance LAN cables, even fire-protected inside steel conduits, failed to meet the minimum flame spread and smoke criteria that HFP-cables must meet in real-scale cable, fire tests at BRE/FRS and Underwriters Laboratories (when tested as a cable in steel conduit system). Life cycle analysis (LCA) via ISO 14040 methodology is used to evaluate the various cabling alternatives using an appropriate functional unit; a CAT 6 communication LAN cabling system in a typical office building, including cable, steel conduit, couplings and supports as required per building codes for the installation. Key environmental impact assessments for energy consumption, greenhouse gas emissions, and human toxicity are all shown to favor the PVC/PFP systems once the steel conduit is included in the analysis to fire-protect the LSZH/PE or PVC/PE cables. The additional fire safety and installation advantages provided by the PVC/PFP cables more than offsets for the environmental burdens associated with the initial manufacture of just the cable, thereby providing superior overall fire safety, environmental performance, and economic benefits versus LSZH/PE and PVC/PE cables in steel conduits.
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摘要 :
Changing environmental interests and new fire safety performance concerns in the wire and cable industry (WCI) have generated studies into the fire hazard and eco-performance of various data and communication cabling system altern...
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Changing environmental interests and new fire safety performance concerns in the wire and cable industry (WCI) have generated studies into the fire hazard and eco-performance of various data and communication cabling system alternatives for computers and local area networks (LAN). To accurately assess the various alternatives, the installed electronic functionality and fire safety performance requirements of the various end-use product options must be equivalent. For high fire performance communication cables (HFP-cables), many existing local and national regulations differentiate between end product performance options and building fire protection needs. High fire-performance, high societal-value based PVC sheathed and perfluoropolymer (PFP) insulated (PVC/PFP) cables can be routed directly in concealed plenum spaces in buildings, while products that do not meet specific high fire performance criteria, such as low-smoke zero-halogen (LSZH/PE) cables or riser-rated cables (CMR or PVC/PE), often must be protected inside other structures that do meet these building fire standards, typically using steel conduit or trunking. However, some low fire performance LAN cables, even fire-protected inside steel conduits, failed to meet the minimum flame spread and smoke criteria that HFP-cables must meet in real-scale cable fire tests at BRE/FRS and Underwriters Laboratories (when tested as a cable in steel conduit system) [10]. Life cycle analysis (LCA) via ISO 14040 methodology is used to evaluate the various cabling alternatives using an appropriate functional unit; a CAT 6 communication LAN cabling system in a typical office building, including cable, steel conduit, couplings and supports as required per building codes for the installation. Key environmental impact assessments for energy consumption, greenhouse gas emissions, and human toxicity are all shown to favor the PVC/PFP systems once the steel conduit is included in the analysis to fire-protect the LSZH/PE or PVC/PE cables. The additional fire safety and installation advantages provided by the PVC/PFP cables more than offsets for the environmental burdens associated with the initial manufacture of just the cable, thereby providing superior overall fire safety, environmental performance, and economic benefits versus LSZH/PE and PVC/PE cables in steel conduits.
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摘要 :
Changing environmental interests and new fire safety performance concerns in the wire and cable industry (WCI) have generated studies into the fire hazard and eco-performance of various data and communication cabling system altern...
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Changing environmental interests and new fire safety performance concerns in the wire and cable industry (WCI) have generated studies into the fire hazard and eco-performance of various data and communication cabling system alternatives for computers and local area networks (LAN). To accurately assess the various alternatives, the installed electronic functionality and fire safety performance requirements of the various end-use product options must be equivalent. For high fire performance communication cables (HFP-cables), many existing local and national regulations differentiate between end product performance options and building fire protection needs. High fire-performance, high societal-value based PVC sheathed and perfluoropolymer (PFP) insulated (PVC/PFP) cables can be routed directly in concealed plenum spaces in buildings, while products that do not meet specific high fire performance criteria, such as low-smoke zero-halogen (LSZH/PE) cables or riser-rated cables (CMR or PVC/PE), often must be protected inside other structures that do meet these building fire standards, typically using steel conduit or trunking. However, some low fire performance LAN cables, even fire-protected inside steel conduits, failed to meet the minimum flame spread and smoke criteria that HFP-cables must meet in real-scale cable, fire tests at BRE/FRS and Underwriters Laboratories (when tested as a cable in steel conduit system). Life cycle analysis (LCA) via ISO 14040 methodology is used to evaluate the various cabling alternatives using an appropriate functional unit; a CAT 6 communication LAN cabling system in a typical office building, including cable, steel conduit, couplings and supports as required per building codes for the installation. Key environmental impact assessments for energy consumption, greenhouse gas emissions, and human toxicity are all shown to favor the PVC/PFP systems once the steel conduit is included in the analysis to fire-protect the LSZH/PE or PVC/PE cables. The additional fire safety and installation advantages provided by the PVC/PFP cables more than offsets for the environmental burdens associated with the initial manufacture of just the cable, thereby providing superior overall fire safety, environmental performance, and economic benefits versus LSZH/PE and PVC/PE cables in steel conduits.
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A new Facilities Decommissioning Certificate Program has been developed at Washington State
University Tri-Cities (WSU TC) in conjunction with Bechtel Hanford, Inc., and the U.S.
Department of Energy. Motivation for development ...
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A new Facilities Decommissioning Certificate Program has been developed at Washington State
University Tri-Cities (WSU TC) in conjunction with Bechtel Hanford, Inc., and the U.S.
Department of Energy. Motivation for development of this Program, the manner in which it has
been developed, the objectives of the Program, and a summary of the content are described.
Lessons learned from the inaugural offering of the Program are also summarized.
This Program has been developed in response to the current and future need for qualified
professionals to direct and manage the variety of activities associated with the deactivation,
decontamination and decommissioning (D&D) of facilities across the nation. Existing
professionals in this area have historically acquired experience from training on
decommissioning projects. Although the demand for qualified D&D professionals nationally
and internationally has kept pace with decommissioning demands to date, many of these
professionals are approaching the end of their careers. The demand for qualified workers is
expected to increase with the aging of the nuclear complex. Additional qualified workers will,
therefore, be required to meet this growing need. The challenge in meeting this need involves the
preparation of people to enter the D&D field in a more effective and efficient manner. This
challenge was addressed by developing a program involving education on topical areas in key
disciplines in addition to D&D technology, practices, and procedural guidelines. The WSU
Certificate Program involves 160 hours of classroom instruction in a modular format on topics
including radiation science; physical and chemical properties of hazardous and non-radioactive
materials; risk assessment and pathway analysis; characterization; regulations; D&D
engineering, technology and practices; and project management. Scientific and engineering
fundamentals and their relevance to D&D concepts and activities are emphasized. The Program
is also designed to provide a D&D context for instruction drawn from projects and case studies.
Capstone modules involve the application of these topics in assessment exercises based on
specific case studies. The target audience for this Program includes existing D&D professionals
wishing to enhance their technical competency, existing technical and management personnel
intending to transfer into this field, and traditional students seeking careers in D&D. Successful
completion of the Program is intended to provide students with the basic tools needed to
accelerate their ability to contribute in D&D projects and to provide employers with an effective
and reliable mechanism to expedite the development of D&D professionals. The establishment
of an appropriate curriculum and identification of qualified instructors have been the key
elements in development of the program.
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Risk-based soil cleanup levels that are protective of groundwater have been calculated for use in environmental remediation activities at the Hanford Site using vadose zone fate and transport modeling. The determination of soil cl...
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Risk-based soil cleanup levels that are protective of groundwater have been calculated for use in environmental remediation activities at the Hanford Site using vadose zone fate and transport modeling. The determination of soil cleanup levels is important because it involves the technical basis for the levels of contamination that can be left in place, which are protective of human health and the environment. The determination of risk-based soil cleanup levels is an especially important issue at the Hanford Site where site conditions such as a semi-arid climate, and a thick vadose zone of over 100 meters necessitate the use of appropriate risk-based methods. In the absence of an alternative risk-based approach, the cleanup levels default to background, detection limits, or simplistic formulas not intended for applications involving these distinctive site conditions. However, the use of vadose zone fate and transport modeling for risk-based applications such as the determination of soil cleanup levels in the vadose zone are not as well established as modeling for groundwater applications. Thus, the use of models in this manner involves additional challenges for the demonstration of the efficacy of its use for risk-based applications, in accordance with federal and state regulatory requirements and guidelines.
An approach has been developed to integrate with federal and state regulatory guidelines in conjunction with the development of the risk-based methodology. Demonstration of integration with these guidelines primarily involves documentation of the objectives of the problem to be solved, the technical basis and rationale associated with the selection of an appropriate risk-based method (e.g., model type and code selection), and documentation associated with the use of the model, e.g., conceptual site model, parameter estimation, uncertainty and assumptions analyses, and model results.
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The benefits of polycarbonate include inherent toughness, transparency, relatively high temperature stability, and wide flow range. These properties have long led to usage in applications that require good aesthetics, dimensional ...
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The benefits of polycarbonate include inherent toughness, transparency, relatively high temperature stability, and wide flow range. These properties have long led to usage in applications that require good aesthetics, dimensional stability, and strong mechanical properties. Looking to build upon these benefits, a new polycarbonate has been developed with a UV-active ketone incorporated in to the resin which allows for cross-linking of the polycarbonate when exposed to UV. This UV-active polycarbonate has similar physical properties to standard polycarbonate (tensile strength, Izod impact, melt flow, etc.). Yet after UV exposure, the new resin shows improvements in chemical resistance and flame retardance of polycarbonate.
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Over 80% of activities of daily living involve grasping or seizing objects with the hand [1]. The carpometacarpal (CMC) joints of the hand and wrist, the five joints that articulate the distal row of carpal bones and the proximal ...
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Over 80% of activities of daily living involve grasping or seizing objects with the hand [1]. The carpometacarpal (CMC) joints of the hand and wrist, the five joints that articulate the distal row of carpal bones and the proximal bases of the five metacarpal bones, are particularly important for prehensile tasks involving the opposition of the ring and little fingers with the thumb, such as during precision grasping. In addition, impairment of the CMC joints can weaken grip strength [2].
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摘要 :
Over 80% of activities of daily living involve grasping or seizing objects with the hand [1]. The carpometacarpal (CMC) joints of the hand and wrist, the five joints that articulate the distal row of carpal bones and the proximal ...
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Over 80% of activities of daily living involve grasping or seizing objects with the hand [1]. The carpometacarpal (CMC) joints of the hand and wrist, the five joints that articulate the distal row of carpal bones and the proximal bases of the five metacarpal bones, are particularly important for prehensile tasks involving the opposition of the ring and little fingers with the thumb, such as during precision grasping. In addition, impairment of the CMC joints can weaken grip strength [2].
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