AIMS Safety Features

Under normal operating conditions, the National Instruments controller monitors for process faults and takes corrective action upon identification. The system will override operator commands issued at the HMI during a safety interlock. The unsafe conditions that result in a process interlock are  

Most of the system interlocks are handled by the embedded NI controller. This is similar to that used in other laboratory-scale reactor systems (Mills and Nicole, 2005) except the Siemens 545 PLCs have been replaced with the National Instruments system. The National Instruments controller monitors the status of the AIMS process variables and takes appropriate action if any interlock conditions are found. In addition to these interlocks, the external heater controllers that are used for the system heating tapes and sampling valve box contain hardwired overtemperature interlocks built-in to these controllers. However, these interlocks only interrupt power to the affected heating device, so the NI controller must still take action to shutdown the rest of the process. 

Power failure is considered a system interlock, but the NI controller cannot take any active measures to return to a safe state. Instead, the system was designed so that in case of a power failure the system shuts down by relieving any pressure in the process lines. However, if this occurs, the process lines are not purged with an inert gas. Thus, when any system maintenance was performed, such as replacing 

---

The construction of the HTR-10 is the first step of the HTGR development strategy in China The objective of the HTR-10 is to verify and demonstrate the technigue and safety features of Modular HTGR and to establish an experimental base for developing the nuclear process heat applications The specific aims of the HTR-10 have been defined as follows ... 

Through broad implementation of inherent and passive safety features and passive systems, ensuring reactivity self-control, passive heat removal under all operating conditions, and perfect confinement of radioactivity in TRISO fuel up to very high temperatures, the CHTR aims to eliminate the need for intervention in the public domain beyond the plant boundaries, in all postulated accidents. 

The FUJI-233Um concept aims to prevent severe accidents and limit their consequences by strongly relying on inherent and passive safety features incorporated in the original design concept. 

During BMN-170 development, the design principles to provide plant safety was aimed at an optimum combination of reliance on intrinsic safety features and application of engineered (active and passive) systems. To be specific, the protection system being developed employs hydraulically suspended reactivity control rods that effectively influence the reactivity and convert the reactor to a sub critical state when flow rate is reduced through the core [XXI-9]. Use of a passive emergency cool down system allows complete removal of residual heat. 

Step 7 Final safety assessment of the plant and evaluation of the probability failure of the structures, systems and components that have been categorized for external events are based on the actual hazard and design methodologies used in the design/qualification (box (10) of Fig. 1). This step aims at fine tuning the engineering safety features to ensure that any structure, system or component can provide the required safety function with the required reliability (Section 4). This step replaces a full scope PSA with simplified probabilistic methodologies. 

Vehicle design affects both the probability and conseqnences of accidents. A distinction is made between the active safety featnres of the vehicle and its crashworthiness. The active safety features aim at making it possible for the driver to control the vehicle in a safe way and to avoid traffic conflicts (Englund etal., 1998). They inclnde ... 

The SSC-K code was used for assessment of the inherent safety features in the KALIMER conceptual design. The SSC-K aims not only at extensive analysis capability and flexibility, but also at sufficiently fast running to simulate long transients in a reasonable amount of computer time. The code is capable of handling a wide range of transients, including normal operational transients, shutdown heat removal transients, and hypothetical ATWS events. The SSC-K code is currently used as the main tool for system transient analysis in the KALIMER development. 

Safety by design should always be the aim, but it is often impossible or too expensive and we then have to rely on procedures. Key features of all procedures are as follows-. 

In a processing facility, the primary aim is to impart effective phase-contacting in the constituents within the safety and temporal constraints prescribed by the particular application. The basic design features of the equipment described in this section help to discern the performance capabilities of candidate geometries in this context. 

The Fido technology is currently under evaluation for use by U.S. military forces. The Fido X and Fido XT are available as commercial off-the-shelf (COTS) items. Consequently, the technology is adequately mature for commercial deployment. However, as a platform technology, the AFP sensor and Fido detection system support broad application to meet explosives detection needs. Further, Nomadics has incorporated the amplification features of AFP into other sensor mechanisms aimed at the detection of analytes that are not explosives related, including other chemicals and compounds of interest in the biomedical and food safety fields. Thus, while the technology is mature enough for commercialization, its potential is far from fully exploited. 

All class teachers and coordinators need to be familiar with the school policy contents and procedures and link the school aims with curriculum-specific policy statements. This will create an appreciation of the wholeness of health and safety management. It will also help to ensure that class teachers, at the heart of the teaching and learning proces, are well informed with expected practice. Similarly, school management, governors and head teachers, will need to ensure needs arising out of health and safety poHcies feature as priority items in the school development plan. 

---