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The Federal Railroad Administration (FRA), together with its industry and state government partners, has tested several types of passenger rail equipment to evaluate the safety aspects of operating these vehicles at higher speeds on existing lines. The FRA's approach to safety at these regimes has been to consider the equipment and the track as an integrated system; neither the track nor the equipment can be considered in isolation. When a vehicle's characteristics are known through analysis and experience, assessment of its safety at high cant deficiency on a given track can be conducted with a portable system comprised of two accelerometers and a global positioning system. The portable system is typically placed on the vehicle's floor where it measures carbody accelerations, vehicle speed, and track location. Recorded data are then compared with the safety criteria established for each vehicle, speed and track condition. This paper describes the safety assessment procedure and the results of some recent tests including those of the Spanish Talgo coach and Amtrak's F-40PH locomotive. >

This paper presents a graphical method for safety assessment of grounding systems. For a grounding system to be safe, the maximum touch and step voltages should not exceed postulated safety criteria. The method presented in this paper is applicable to the safety criteria of the IEEE Standard 80 as well as the IEC-479-1. Both standards define safety criteria in terms of allowable body current. The allowable body current is then translated into the allowable touch and step voltages. Thus, safety assessment of a grounding system is referred to a procedure by which the actual maximum touch and step voltages are computed and compared to the maximum allowable (safe) touch and step voltages. Since the IEC-479-1 safety criteria are nonlinear, a graphical method is presented for safety assessment.

Structural designs for composite laminated systems can be optimized for a fail-safe in-service performance by introducing the built-in cumulative-damageindicators for the progressive degradation of material properties. This design methodology is based on the concepts of the characteristic failure signature (CFS), the cumulative-damage-states and a load drop sequence that characterize the progressive accumulation of damage. The cumulative damage mechanics is based on the 3D laminate analysis that is used to predict a nonlinear stress/strain response, accumulation of damage and failure behavior. The nonlinear analysis involves an incremental formulation that couples the 3D laminate analysis with a progressive ply-failure methodology. The failure signatures are shown to have unique “safety features” that depend on the ply stacking sequence and predominant loading. A quantitative description of the failure process is provided by the corresponding load-drop sequence. Various examples of failure envelopes, characteristic failure signatures, a new safety criterion and the “safe CFSs” that lead to the desired controlled failures are discussed for anisotropic laminates. The safety criterion may serve as a basis for the structural safety requirements.

The main objective of this paper is to give an overview of basic concepts and definitions of terms related to the 'measurement of slipperiness' from the onset of a foot slide to a gradual loss of balance and a fall. Other unforeseen events prior to falls (e.g. tripping) are sparingly dealt with. The measurement of slipperiness may simply comprise an estimation of slipping hazard exposures that initiate the chain of events ultimately causing an injury. However, there is also a need to consider the human capacity to anticipate slipperiness and adapt to unsafe environments for avoiding a loss of balance and an injury. Biomechanical and human-centred measurements may be utilized for such an approach, including an evaluation of relevant safety criteria for slip/fall avoidance and procedures for validation of slip test devices. Mechanical slip testing approaches have been readily utilized to measure slipperiness in terms of friction or slip resistance but with conflicting outcomes. An improved understanding of the measurement of slipperiness paradigm seems to involve an integration of the methodologies used in several disciplines, among others, injury epidemiology, psychophysics, biomechanics, motor control, materials science and tribology.

In the first part (in Chapter 4), we have mentioned that the failures altering a product can be dispatched into several classes according to the seriousness of their impact on the system itself, on its user, and on its environment. The set of the four classes — benign, significant, serious and catastrophic — constitutes an example of such classification. In this chapter, we consider faults whose external consequences are dangerous, for example serious or catastrophic. Their analysis refers to the safety criterion.

Reduced working hours and increased caesarean delivery rates have resulted in less exposure to intricate deliveries by obstetrics trainees. Though trainees may not be exposed to these deliveries as part of their training, conversely they may be expected to be proficient in them once starting independent clinical practice. This study aims to identify the verbal and non-verbal components of three intricate deliveries – Kiellands, non-rotational and assisted breech. Labour and delivery nursing staff were asked to identify those clinicians who they considered to be particularly skilled in intricate deliveries. Those identified consistently were invited to participate in the study. With written consent participants were then videoed performing each type of delivery on a model in order to identify the verbal and non-verbal components of the delivery. Two clinicians reviewed videos. The initial summary was then circulated to all participants for their approval. Themes identified included the need for careful assessment of suitability, the role of the multidisciplinary team, need for careful and appropriate communication with the parents, the technique of delivery itself and postpartum care and documentation. Overall the clinicians balanced respect for the “elegant technique” of intricate deliveries with careful assessment and when to stop should safety criteria not be met. There is still a role for intricate deliveries in modern obstetric practice, and a need for good quality holistic training programs on how best to perform such deliveries. By identifying verbal and non-verbal components of skilled deliveries these can then be translated into an useful educational tool.

This analysis meets the requirements of HNF-7098, Criticality Safety Program, (FH 2001a). HNF-7098 states that before starting a new operation with fissile material or before an existing operation is changed, it shall be determined that the entire process will be subcritical under both normal and credible abnormal conditions. To demonstrate the Incredibility Principle is satisfied, this Criticality Safety Evaluation Report (CSER) shows that the form or distribution is such that criticality is impossible. This evaluation demonstrated, that on the basis of effective {sup 235}U enrichment, criticality is not possible. The minimum blanket assembly exposure is 4,375 MW{sub t}d/MTU for fissile material that is shown to fulfill the Incredibility Principle safety criterion on the basis of enrichment.

The purpose of this performance specification is to document the necessary requirements and criteria for procurement of the Hanford K East Basin Sludge Transportation System, for use by the Fluor Hanford Spent Nuclear Fuel (SNF) Project. The Sludge Transportation System shall be used for the onsite shipment of Hanford K Basin sludge to T Plant for subsequent storage. Fundamentally, the system shall consist of a shielded shipping cask (packaging), transportation trailer, and inner sludge containers (container). The scope of this specification includes a description of the system payload and facility handling interfaces, and the performance requirements for the packaging (Cask), Trailer, Large Containers, Process Shield Plate, and associated Devices. This specification also provides the safety criteria required for the development of a Hanford onsite Safety Analysis Report for Packaging (SAW), which shall document the technical justification for US. Department of Energy, Richland Operations Office (RL) approval of the transport of the sludge packaging on the Hanford site. However, the development of the onsite SARP is not part of the scope of this procurement.

The report describes presentations and discussions at a seminar held at Risø on March 22-23, 2000. The title of the seminar was NKS/SOS-1 – Safety Analysis. It dealt with issues of relevance for the safety analysis for the entire nuclear safety field (notably reactors and nuclear waste repositories). Such issues were: objectives of safety analysis, risk criteria, decision analysis, expert judgement and risk communication. In addition, one talk dealt with criteria for chemical industries in Europe. The seminar clearly showed that the concept of risk is multi-dimensional, which makes clarity and transparency essential elements in risk communication, and that there are issues of common concern between different applications, such as how to deal with different kinds of uncertainty and expert judgement.

This paper describes methods and tools for automated safety analysis of UML statechart specifications. The general safety criteria described in the literature are reviewed and automated analysis techniques are proposed. The techniques based on OCL expressions and graph transformations are detailed and their limitations are discussed. To speed up the checker methods, a reduced form for UML statecharts is introduced. Using this form, the correctness and completeness of some checker methods can be proven. An example illustrates the application of the tools developed so far.

Background and Objectives Continuous subcutaneous insulin infusion therapy has been in use for more than 20 years. The device was included on the list of reimbursable products and services in France in 2000. At the time, 246 patients were being treated in the Provence-Cote d9Azur region. The Provence Diabetes network was created in order to meet regional organisational needs during device deployment, to establish deployment rules, and to ensure the safety, quality and consistency of practices. Our objective was to assess the results obtained for the year 2008. Programme The Provence Diabetes network currently includes nine pioneer centres (including two paediatric centres), over 100 endocrinologists in independent practice in charge of treatment follow-up, 13 providers, four device manufacturers, state-registered nurses, dieticians, nonhospital podologists and health care institutions. Results In 2008, 275 patients started insulin infusion therapy within the network and 1193 patients were undergoing regular monitoring. Overall, 89% of scheduled patients had undergone yearly evaluation. Their average age was 46 years, 84.3% had type 1 diabetes (average duration 19.5 years). They had been on insulin infusion for a mean of 5 years. When insulin infusion therapy was initiated, their glycated haemoglobin (HbA1c) was 8.3%. By the time of the yearly evaluation, their metabolic status had markedly improved; HbAIc had fallen to 7.5% (p Discussion and Conclusions Analysis of metabolic results and patient education in patients evaluated in 2008 within the Provence diabetes network has established the efficiency and safety of continuous subcutaneous insulin infusion therapy at a regional level (better metabolic balance and few acute accidents). This was despite more widespread diffusion of the device after national health insurance coverage was granted. In addition, the network has provided added value as regards application of regulations by ensuring consistency of practices across health care centres and by professionals (common protocols and procedures), organising training, centralising medical device vigilance and making sure that everyone applies the necessary safety criteria. Contexte et objectifs Le traitement par pompe a infusion sous cutanee existe depuis plus de 20 ans. En 2000, date d9inscription au TIPS, 246 patients sont traites par pompe a insuline dans la region PACA (hors Alpes –Maritimes)- Corse. Pour repondre aux besoins d9organisation regional lors du deploiement de ce traitement, afin d9en fixer les regles et d9en garantir la qualite, la securite et l9homogeneite des pratiques le reseau Diabete Provence est cree. Programme Cette structure regroupe aujourd9hui 9 centres initiateurs (dont 2 pediatriques), plus de 100 endocrinologues liberaux de suivi, 13 prestataires, 4 fabricants de pompe, des IDE, dieteticiens, podologues liberaux et des etablissements de sante. Resultats Au cours de l9annee 2008, 275 patients ont debute un traitement par pompe a insuline au sein du reseau et 1193 sont suivi regulierement. 89 % des patients a evaluer ont beneficie d9une evaluation annuelle du traitement par pompe a insuline. L9âge moyen des patients ayant beneficie d9une evaluation annuelle en 2008 est de 46 ans, 84,3% des patients presentent un diabete de type 1, la duree moyenne du diabete chez ces patients est de 19,5 ans, et les patients sont traites par pompe a insuline depuis 5 annees en moyenne. L9HbA1c initiale de ces patients lors de la mise sous pompe etait de 8.3% et est de 7,5% lors de l9evaluation annuelle (p Conclusion L9analyse des resultats metaboliques et de l9education des patients traites par pompe a infusion sous cutanee d9insuline evalues en 2008 au sein du reseau Diabete Provence permet de confirmer, a l9echelle d9une region, l9efficacite et la securite du traitement malgre la diffusion du traitement depuis son remboursement (meilleur equilibre metabolique et peu d9accident aigu). Une des plus values du reseau est de veiller a l9application des textes reglementaires en permettant une homogeneisation des pratiques entre les differents centres et professionnels de sante (protocoles et procedures en commun), en organisant la formation des differents intervenants, en centralisant la materiovigilance et en verifiant que les criteres de securite soient bien appliques par tous.

This paper reports on the present schedule of JET which includes an experimental campaign with D-T plasmas at the end of the Project programme. A dedicated facility, the Active Gas Handling System, (AGHS), has been designed and is being commissioned to process the torus exhaust streams and to recycle tritium and deuterium. The AGHS is expected to process a maximum throughput of 30 g tritium daily and total tritium inventory will not exceed 90 g. The design is subject to a comprehensive safety analysis which must show that stringent safety criteria are met. In parallel to the AGHS installation, the JET torus and its auxiliary systems are being analyzed for compliance with the same safety criteria. Modification are being implemented where required. JET will be the first experimental facility where the tritium fusion fuel processing cycle will be closed (albeit without breeding) and hence important experience and experimental data are expected to be gained for the next generation of fusion devices.

Helmet Mounted Displays (HMD) are now an essential element in fast jet aircraft cockpits and the demanding safety requirements must be maintained. Exposure to high-speed air- blast was a fundamental requirement of a developmental HMD produced by BAE SYSTEMS. Safety criteria based on stability, strength and aerodynamic loads meant that reliance on an empirical development was no longer appropriate. Success was achieved from a combination of experience, analysis, design and testing. Computational Fluid Dynamics modeling combined with validation testing in a wind tunnel provided a vital understanding of the aerodynamic loads developed during the windblast event and significantly reduced developmental risk.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Job rotation is one method that is sometimes used to reduce exposure to strenuous materials handling; however, developing effective rotation schedules can be complex in even moderate sized facilities. The purpose of this research is to develop methods of incorporating safety criteria into scheduling algorithms to produce job rotation schedules that reduce the potential for injury. Integer programming and a genetic algorithm were used to construct job rotation schedules. Schedules were comprised of lifting tasks whose potential for causing injury was assessed with the Job Severity Index. Each method was used to design four job rotation schedules that met specified safety criteria in a working environment where the object weight, horizontal distance and repetition rate varied over time. Each rotation was assigned to a specific gender/lifting capacity group. Five versions of the integer programming search method were applied to this problem. Each version generated one job rotation schedule. The genetic algorithm model was able to create a population of 437 feasible solutions to the rotation problem. Utilizing cluster analysis, a rule set was derived from the genetic algorithm generated solutions. These rules provided guidelines for designing safe job rotation schedules without the use of a computer. The advantages and limitations of these approaches in developing administrative controls for the prevention of back injury are discussed.

In January, 1995 a collaborative effort to improve radiological consequence analysis methods and tools was initiated between the V.G. Khlopin Institute (KRI) and Sandia National Laboratories (SNL). The purpose of the collaborative effort was to transfer SNL`s consequence analysis methods to KRI and identify opportunities for collaborative efforts to solve mutual problems relating to the safety of radiochemical facilities. A second purpose was to improve SNL`s consequence analysis methods by incorporating the radiological accident field experience of KRI scientists (e.g. the Chernobyl and Kyshtym accidents). The initial collaborative effort focused on the identification of: safety criteria that radiochemical facilities in Russia must meet; analyses/measures required to demonstrate that safety criteria have been met; and data required to complete the analyses/measures identified to demonstrate the safety basis of a facility.

Gas circulators are critical to the safe and economic operation of nuclear power stations. When significant maintenance work or design changes are required for the gas circulators, plant engineers must provide detailed justifications of proposed changes which demonstrate that relevant technical and safety criteria have been satisfied. The paper describes the Gas Circulator Design Advisory System (GCDAS) which is a Web based decision support system utilising case based, knowledge based and database techniques to provide engineers with focused and prioritised information relating to a requested design change.

This report is a collection of studies performed at Sandia National Laboratories in support of Phase One (inert debris) for the Risk and Lethality Commonality Team. This team was created by the Range Safety Group of the Range Commander`s Council to evaluate the safety issues for debris generated during flight tests and to develop debris safety criteria that can be adopted by the national ranges. Physiological data on the effects of debris impacts on people are presented. Log-normal curves are developed to relate the impact kinetic energy of fragments to the probability of fatality for people exposed in standing, sitting, or prone positions. Debris hazards to aircraft resulting from engine ingestion or penetration of a structure or windshield are discussed. The smallest mass fragments of aluminum, steel, and tungsten that may be hazardous to current aircraft are defined. Fragment penetration of the deck of a small ship or a pleasure craft is also considered. The smallest mass fragments of aluminum, steel, or tungsten that can penetrate decks are calculated.

This report is the first in a series to report on speciation of organic carbon in Hanford waste storage tanks. The comparison of the existing total organic carbon with oxalate and limited analyses of other organic species (acetate, formate, and normal paraffin hydrocarbons [NPH]) are reported. All of the data have been previously reported by the Grout and Characterization programs; the information includes all of the publicly available data through October 1996. Oxalate data were reported for 33 tanks, TOC data were reported for 82 tanks, and both oxalate and TOC data were available for 27 tanks. Of these 27 tanks, seven were found to have greater than 80% of the TOC identified as oxalate: 241-BY-104, 241-BY-105, 241-BY-106, 241-BY-110, 241-S-109, and 241-SX-108. Eighty percent accountability has been tentatively established as a minimum goal of the Organic Safety Program for speciation of TOC. Accountability of TOC through speciation will allow more accurate estimate of the potential energy content of the wastes as currently stored. Of the remaining 19 tanks, seven had between 40 and 80% of the TOC identified as oxalate, and eleven had less than 35% of the TOC identified. Of these, only five tanks had segment results that were greater than 1% TOC, and none was above 2%. Since the cur-rent safety criterion outlined in the Safety Analysis is 4.5% TOC, it may be determined that the further analyses of these tank wastes are not necessary. If additional analyses are deemed necessary, minimal work may be required, possibly limited to ion chromatography (IC), ion pair chromatography and capillary zone electrophoresis (CZE). Additional speciation work is planned for this fiscal year in both the Organic Tanks Safety and Characterization programs. The Characterization program reports acetate and formate data in addition to the oxalate data for all the tank cores it processes.

The general safety criteria are reviewed; examples of several different safety programs are illustrated; cost and schedule information are presented; and outlines of general safety considerations and specific safety design requirements and solutions are listed. A suggested program approach is covered in some detail.

This document reviews the hazards associated with the storage of organic complexant salts in Hanford Site high-level waste single- shell tanks. The results of this analysis were used to categorize tank wastes as safe, unconditionally safe, or unsafe. Sufficient data were available to categorize 67 tanks; 63 tanks were categorized as safe, and four tanks were categorized as conditionally safe. No tanks were categorized as unsafe. The remaining 82 SSTs lack sufficient data to be categorized.Historic tank data and an analysis of variance model were used to prioritize the remaining tanks for characterization.

Risk Analysis techniques are more and more frequently applied in the design of industrial plant. The growing complexity of the systems together with the need to develop increasingly reliable solutions make it essential that the plant design decisions are backed up by an in-depth, global knowledge of the most important specific problems of the plant itself.

This report documents additional criticality safety analysis calculations for small diameter containers, which were originally documented in Reference 1. The results in Reference 1 indicated that some of the small diameter containers did not meet the criteria established for criticality safety at the Portsmouth facility (K{sub eff} +2{sigma}

The role of performance assessment was discussed by a group of panelists and the participants of the 20th MRS symposium on the Scientific Basis for Nuclear Waste Management. Panel members were Professor Thomas Pigford, Dr. Alan Cooper, and Dr. Patrik Sellin; Dr. Michael J. Apted served as moderator. For discussion purposes, performance assessment (PA) was defined as the analysis of the release of radionuclides from a repository system of barriers to the accessible environment. As stated by some of the panelists, performance assessment: provides the major tool for the dialog between the implementor and the regulator; assesses the degree of safety of a repository with respect to national and international safety criteria; identifies the components and processes of the system that are responsible for safety; identifies the key uncertainties; and serves as a tool for scientific management that can be used to make decisions regarding design and research priorities. The concerns and their proposed solutions are discussed.

This report contains safety criteria for the storage of ferrocyanide bearing waste sludges in Hanford underground waste storage tanks. In addition, the tank wastes are categorized with this criteria into SAFE, CONDITIONALLY SAFE, and UNSAFE categories based on available historical records and sample information. Fourteen (14) tanks are classified as CONDITIONALLY SAFE, while four (4) C-Farm tanks are categorized as SAFE. This report therefore provides a technical basis to resolve the ferrocyanide safety issue for these four tanks and supports their removal from the Watch List. The 14 CONDITIONALLY SAFE tanks will be re-evaluated in a future revision to this report as representative sample data becomes available. It is anticipated that the 14 tanks will be re-categorized as SAFE at that time.

In going about their daily-life individuals continuously assess situations and make decisions on whether the risk associated to a particular action is justified. Such decisions are mostly made under conditions of uncertainty and involve value judgments that normally cannot be explicitly expressed in terms of quantitative criteria. This is often the case when the risk is of a voluntary nature,i.e., it is taken as a free choice (i.e., smoking, down hill skiing). On the other hand, when the individual cannot fully chose to avoid exposure to risk, it is termed as involuntary risk (e.g., natural disasters, large industrial accidents) and the decision making process needs to be more explicit using quantitative data. Moreover, people are generally willing to expose themselves to quite different levels of risk depending on whether it is of a voluntary or non-voluntary nature.

Nuclear weapon limitation and accumulation of power plutonium put the problem of its utilization in already operating and constricting NPPs with VVER-type reactors. Elementary way of Pu-utilization in fuel cycle of VVER-reactor is direct replacement of Pu-fuel fraction by MOX fuel design not accompanied an essential change of core and regimes of its operation. It seams necessary that the optimization of both fuel elements and assembly design is needed for case of MOX fuel use. The first way of weapon plutonium introduction in VVER fuel cycle is believed to use in early stage The feature of physics of core with MOX fuel limit a fraction of MOX fuel assembly until 1/3 of core.

This is the 45-Day report for the fiscal year 1994 Tank 241-B-102 auger sampling characterization effort. Only one of the two planned auger samples was received by the 222-S Laboratory, however it was decided to begin the 45-day clock and issue a report based on receipt of the first auger sample. Included are copies of the differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) scans as requested. Also included is a copy of any immediate notification documentation, chain of custody forms, the hot cell work plan, extruded segment [auger] description sheets, and total alpha data. The TGA percent moisture results are below the safety criteria limit of 17% in a subsample taken approximately five minutes after extrusion and a second subsample taken from the lower half of the auger. Verbal and written notifications were made as prescribed. The DSC analysis of all subsamples indicates the presence of fraction exotherms, however the results are a factor of two or more below the notification limit of 523 Joules/gram (J/g). Total alpha results are all below the detection limit. In some cases, the tank characterization plan (TCP) accuracy and precision criteria are not met. If a re-run was not performed when a TCPmore » quality control limit was not met, then reasons for not performing the re-run are provided.« less

The space radiobiology program in Russia is aimed at obtaining fundamental data for developing radiation safety criteria. These criteria are necessary for long - term space missions. This program includes : -substantiation of radiation hazard estimation principles based on the radiation risk conception, -investigation of the radiation affection regularities under the combined influence of the spaceflight factors, -experimental investigation of the HZE-particle delayed effects and acute somatic effects induced by protons and electrons, -individual radiosensitivity investigation, -mathematic modeling of radiobiological effects, -radiobiological basis of control and forecast of radiation influence in space, -development of methods and means of an organism's radioresistance increase.

This document describes the validation of KENO V.a using the 27-group ENDF/B-IV cross section library for highly enriched uranium and beryllium neutronic systems, and is in accordance with ANSI/ANS-8.1-1983(R1988) requirements for calculational methods. The validation has been performed on a Hewlett Packard 9000/Series 700 Workstation at the Oak Ridge Y-12 Plant Nuclear Criticality Safety Department using the Oak Ridge Y-12 Plant Nuclear Criticality Safety Software code package. Critical experiments from LA-2203, UCRL-4975, ORNL-2201, and ORNL/ENG-2 have been identified as having the constituents desired for this validation as well as sufficient experimental detail to allow accurate construction of KENO V.a calculational models. The results of these calculations establish the safety criteria to be employed in future calculational studies of these types of systems.

An important part of the Hanford environmental mission is the packaging, transportation, and storage of solid radioactive wastes in metal drums. Presently storage drums are placed four to a wooden pallet with the drums banded to each other. Palletized drums are stacked three units high in pre-engineered steel structures in the 200 Area of the Hanford site. Permitted storage space is expensive to construct, maintain, and operate. Storage capacity is increased if additional drum can be stacked within existing facilities and a cost savings over new construction realized. The purpose of this plan is to outline the testing required to provide the safety criteria for elevated (i.e., tiers of four high) drum storage. The major safety concern with elevated drum storage is the danger of a significant fire in the storage facility. The major fire load within the storage facilities is combustible material contained in the drums. If a seismic event, fork lift accident, or other credible incident were to cause drum failure or lid separation, combustible material could be available for fuel. To increase the initial burn in the facilities, the drums must spill their combustible contents, making them free for ignition. If it can be shown that theremore » is not sufficient damage to the drums to allow for release of their solid contents, then the data used for safety documentation will be re-examined. Preliminary tests conducted in the configurations detailed in this test plan have shown that drums maintain their integrity; that is the drum covers remain attached and the drums do not breach. These tests will be conducted by Westinghouse Hanford Company, Equipment Development organization, who is the designated DOE Center of Excellence to conduct drop tests for Department of Transportation (DOT) certification of DOE designed packages and containers.« less

Analysis of shattered automotive glass for determining particle size, shape and count is legally required to demonstrate that safety criteria have been met. Manual methods are labor intensive, subjective and prone to errors. This paper presents an approach for automating this analysis. Problems associated with missing boundary segments, can cause serious errors unless corrective measures are applied. Techniques for efficient extraction of particle boundaries and restoration of missing segments are presented.© (1993) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

One of the major contributions of E. L. Carstensen to medical ultrasonography lies in the research studies by him and his colleagues on biophysical mechanisms for biological effects. These studies have done much to provide a basis for predicting conditions under which ultrasound will affect living systems. The scientific information that now exists makes possible an improved approach to decisions on safety for diagnostic ultrasonography. In particular, estimates of the maximum temperature produced in a sonographic examination provide an index that can be used to ensure safety from thermal hazards.

Grounding has a significant impact on personnel and property safety, and is an integral part of electrical system design. Specific areas relating to safety criteria, system grounding, and equipment grounding that are either neglected or not covered in sufficient detail in presently published standards, guides, and codes are discussed. Some considerations and recommendations are presented. The major purpose of system grounding is to improve system safety by using the earth as a reference. The type, size, and location of the resulting grounds must be determined in accordance with the National Electrical Code (NEC) and good engineering judgement. The connection of a specific point of an electrical system to the earth creates a potential reference point for that electrical system. By doing so, overvoltages are controlled and limited, contributing to safe system operation. >

In 1981, after over three years of study and discussion, the technical specialists in the United Nations Committee on the Peaceful Uses of Outer Space agreed to a report which provided general safety criteria; a suggested format for notification for reentering space vehicles containing nuclear power sources; suggested improvements in orbit prediction; and recommendations relating to the search and recovery of a nuclear power source. The results of that first consensus on the use of nuclear power sources are summarized to provide an historical framework for developing international norms on the use of nuclear power sources in outer space.

Previously presented results for the oxidation kinetics and hence the spontaneous combustion propensity of six Scottish bituminous coals are reappraised in terms of ignition times, an aspect not considered previously. All six coals could be considered unsafe to ship according to safety criteria based on the spontaneous combustion propensity, but at least two of them have ignition times so long that no incident would be expected on an export voyage. The test for assessing spontaneous combustion propensity does not alone appear to be an adequate criterion for safety in transport.

Long-term structural health monitoring (SHM) systems need intelligent management of the monitoring data. By analogy with the way the human brain processes memories, we present a bio-inspired memory model (BIMM) that does not require prior knowledge of the structure parameters. The model contains three time-domain areas: a sensory memory area, a short-term memory area and a long-term memory area. First, the initial parameters of the structural state are specified to establish safety criteria. Then the large amount of monitoring data that falls within the safety limits is filtered while the data outside the safety limits are captured instantly in the sensory memory area. Second, disturbance signals are distinguished from danger signals in the short-term memory area. Finally, the stable data of the structural balance state are preserved in the long-term memory area. A strategy for priority scheduling via fuzzy c-means for the proposed model is then introduced. An experiment on bridge tower deformation demonstrates that the proposed model can be applied for real-time acquisition, limited-space storage and intelligent mining of the monitoring data in a long-term SHM system.

Several intelligent transportation system (ITS)-based methods have been identified across North America to provide advance warning for end-of-green indication at high-speed signalised intersections. One of these is the installation of an advance warning signal (AWS) system. In the state of Utah, the Utah Department of Transportation installed AWS systems at three locations in the Salt Lake Valley to provide advance warning to drivers on the change in signal indication from green to yellow and, ultimately, to red. The current installations were determined to be successful based on speed variability and safety criteria, thus introducing the need to develop proposed guidelines for installation and to identify future system locations. The purposes of this study are to outline guidelines for ITS-based AWS installation and to present an evaluation procedure for comparison of candidate sites. The methodology and procedure summarised can be used by other governing agencies to fulfil similar needs in their respective jurisdictions.

This paper investigates a methodology for quantitatively evaluating the safety of an IVHS system. The methodology provides a technical basis for establishing the target safety levels for designing the safety-critical components of an IVHS system, in particular those that perform control functions. In addition, this methodology also provides a means for specifying the safety criteria for an automatic controlled vehicle based on the predefined target safety levels.

After manufacture and before retail, ice hockey helmets must pass safety standard tests based primarily on multiple impacts at several global sites to receive certification. Unknown is the effective “shelf life” of these products; that is, do material and construction properties deteriorate with aging to a point below the impact criteria for certification? To address this question, a prospective 6 year study has been completed to investigate the effects of aging on hockey helmet impact attenuation. A longitudinal study (2001–2007) was performed on five models of ice hockey helmet to investigate the effects of aging on these helmets’ impact attenuation characteristics. Helmets were tested on the date of manufacture and years two and six (Y0, Y2, and Y6). The five brands (Nike-Bauer-3000, Nike-Bauer-4000, Nike-Bauer-5000, CCM-HT500, and Jofa-690) were evaluated according to ASTM 1045-99 protocol, impacting four sites: the crown, front, rear, and side. All helmets were stored at ambient temperatures 20±4°C and relative humidity between 10 and 50%. Helmets in Y2 and Y6 did not have prior impacts before testing. Peak acceleration (PA, g) and severity index (SI) were calculated for third impacts and compared between years. In general, PA and SI measures remained within safety criteria levels for all helmets and sites during all testing intervals (that is, all met certification standards). Though some specific helmet/site differences were noted, no substantial change in impact attenuation was observed. Visual inspection of helmets postimpact showed no conspicuous damage to liner or shell, though in several instances the binding glue had disintegrated allowing liners to shift or fall away from the shell. From these results, contemporary ice hockey helmets retain their robust impact attenuation characteristics even after several years of storage, though adhesive embrittlement needs to be addressed. Further testing should evaluate the viability of used helmets in a similar prospective manner to ensure safe helmet function.

The International Food Biotechnology Council (IFBC) was organized in 1988 to develop criteria and procedures to evaluate the safety of foods produced through genetic modification. The specific objective was to provide a comprehensive, scientifically based report, with extensive literature references, and a glossary of terms for this new field, for safety criteria of foods and food ingredients derived from genetically modified plants and microorganisms. However, the immense scope of the subject required restriction to three general categories of food products: foods and food ingredients derived from microorganisms, single chemicals and simple mixtures, and whole foods and other complex mixtures. Not considered were foods derived from

There are similarities between the aerospace and nuclear industries regarding safety. In both cases we are dealing with sophisticated technology, equipment, processes and strong interface with human behaviours. This situation is well understood in both industries. However, there is a range of uncontrolled accident risk as a consequence of poor management and lack of appropriate measures to prevent events that can result in accidents, such as the tragic accident in Columbia.

The correct maintenance of the suspension system elements is important for the safety and comfort of automobiles, but there are no simple and reliable methods to evaluate their state. This paper focuses on shock-absorbers, since they suffer ageing, due to fatigue. The research team has proposed a theoretical-experimental methodology to study the influence of the ageing process of dampers on safety. This methodology solves the difficulties that arise when using pure theoretical or pure experimental approaches. In this methodology, a mathematical model is experimentally validated. Then, manoeuvres that reproduce critical conditions are simulated with several degrees of shock-absorber wear in order to study its influence. As a conclusion, it has been found that the worst condition for safety is curved movement on an irregular surface. Working on these results, the authors are establishing limits for this ageing process based on objective safety criteria.

In an effort to develop acoustic safety criteria for marine mammals that may be exposed to impulsive sounds a masked temporary threshold shift (MTTS) experimental approach was used. Two dolphins, Tursiops truncatus, and two white whales, Delphinapterus leucas, were systematically exposed to increasing levels of impulsive sound (S‐1) under water, then tested to threshold at three pure‐tone frequencies (S‐2) under water in the presence of controlled masking noise. One hearing frequency tested was at the pulse peak frequency, with the other two S‐2 test tones at higher frequencies. Behavioral responses were monitored and hearing thresholds were ascertained to determine if criterion (6‐dB increase over baseline) was reached. Thresholds were estimated using the free response paradigm method and an up–down staircase psychophysical procedure for stimulus presentation in open water in San Diego Bay. These data suggest that the rapid rise time of the leading edge in 1‐s tones used in a previous study is not responsible for producing MTTS. Results of the present study add to the existing knowledge of MTTS for marine mammals and provide the first data on MTTS in cetaceans for impulsive sounds. [Work supported by the Office of Naval Research.]