Room Operating Specifications

Most coal preparation plants use Instrumentation to inform the control room operator of equipment status and guide the employees within the plant in the manual adjustment of the set points on the process equipment. Many unit operations are not equipped with any instrumentation and successful implementation of these unit operations relies totally upon the experience of an employee charged with the responsibility of monitoring specific pieces of process equipment. New plants are being designed with increased levels of automation and on-line instrumentation however, the investment in instruments is only a small fraction of comparable investments in other process industries. For example, the project team visited two modern coal preparation plants in the Appalachian coal fields which cost 75,000,000 and the total on-line instrumentation investment was approximately 150,000. 

Specifically, a second level of voltage protection should be provided for Class IE equipment in addition to the existing protection based on detecting the complete loss of offsite power to the Class IE buses. The second level should have two separate time delays before alerting the control room operator and automatically separating the Class IE buses from the offsite... 

Section 9.4.1). In the event of an outside air contamination signal, the outside air intake is closed and the filter train fan is energized. Outside air from the other air intake as well as some room air is directed through the filter train. If a contamination signal is received from the second outside air intake, it will also close. The control room operator can then manually select the least contaminated outside air intake. Identification of potential hazardous gas sources and releases at or in the vicinity of a specific plant site, and analysis of the resulting concentration in the control room, are the... 

Specifically, the RCS and reactor vessel vent systems shall incorporate such design features as high point venting of the RCS and reactor vessel, remote control room operation, positive valve indication (located in the control room) and environmentally and seismically qualified equipment. Also, the vents should not cause an unacceptable increase in the probability of a LOCA, should not challenge containment integrity, and should be designed with sufficient redundancy to assure a low probability of inadvertent or irreversible actuation. 

The ALMS is part of the NSSS Integrity Monitoring System and is described in CESSAR-DC, Sections 7.7.1.6.1 and 7.7.1.6.2. The function of the ALMS is to detect a leak at specific locations or within specific components in the primary system including the primary safety valves. The ALMS provides the control room operator with a direct and unambiguous method of determining the position (open or closed) of the pressurizer safety valves as required by NUREG-0737. 

The control room operator should be informed of the occurrence of an earthquake by means of the installed seismic instrumentation. Subsequent responses should include an evaluation of recorded earthquake motion in comparison with the specific design of safety related items, a walkdown evaluation of the damage to the plant and an evaluation to determine the readiness of the plant for the resumption (or continuation) of operation following the occurrence of an earthquake. 

The worked example that expresses some of the human factors best practice discussed above is based on an energy distribution system—specifically, the part of the total system that deals with the storage of gas. In this scenario, the task is concerned with alarms that warn control room operators of abnormal states. 

The remaining measuring channels, located in a second chassis, measure radiation levels associated with operating specific experimental facilities. These channels are not required by Technical Specifications, but are described in the Safety Analysis Report. Each beam port has an associated radiation monitor channel, with the detector located on the Reactor Laboratory walls in line with the radiation beam that would be emitted if the beam ports were operated with plugs and external shields removed. A fifth channel detector is located beside the pneumatic tube send-receive station in room 43. This channel has a remote indicator, which provides both dose rate readout and alarm on high radiation level. All five of these detectors annunciate via the EXPERIMENTAL FACILITY RADIATION LEVEL HIGH annunciator when high alarm setpoints are exceeded. These are not connected to the external evacuation alarm. 

When any maintenance bypasses or overrides have been applied the SIS circuitry must be arranged to provide a flashing warning indicator in the control room. Operators must always be aware of the particular override in force. Therefore, a specific alarm indicator... 

The specific events that led to the Chernobyl accident began on Friday, April 25, 1986. Very early in the morning ( 1 am) control room operators at Unit 4 reactor began a planned power reduction that reduced core power by about 50 % down to 1600 MWt (US NRC, 1987). By the afternoon of the 25 , the Central Electricity Board requested that no further power reductions occur at the plant to ensure that local power needs were met. At approximately this same time, as part of the test, the emergency core cooling systems were shut down (US NRC, 1987). 

While Martin waits for the others to install the calibrated pressure gauge, he explains to Nate that the pressure transducers need a power supply to get the signal from the basement to the control room. The operating specifications mandated 10 to 20 volts, but on further inspection Martin believes this may not be enough voltage. He increases the power supply to over 25 volts. The phone rings and the operator answers it. 

In SED VII and VIII, reference was made to the possible deleterious effects of low concentrations of anaesthetic agents in the atmosphere of operating rooms. More specifically, the influence on abortion rates and congenital anomalies of children bom to female anaesthetists was described. Desbaumes et al. (2C) measured brominated metabolites of halothane in the urine of 18 members of the operating theatre staff and found a striking difference between women and men (14.59 mg/1 and 3.04 mg/1 respectively). This difference may be explained by the fact that women staff members are more likely to be continuously present in the operating theatre or that they retain halothane more easily in their body fat. Only the first explanation is consistent with the sex difference in fluroxene toxicity found in mice (3), as this toxicity was more marked in males. 

The oxygen release rate is directly proportional to the cross-sectional area of the candle for a specific composition and also depends on the linear bum rate. Lower fuel contents decrease the bum rate slightly, eg, ca 2 wt % iron is the lower limit for rehable room temperature operation. Low temperature starts require at least 3.5 wt % iron. Another factor is direction of flow of the evolved gas. If the hot oxygen flows over the unbumed portion of the candle, as much as 15% rate iacreases can be produced. The bum time is halved for each 3.4 MPa (500 psi) pressure rise. The highest pressure that can be produced is ca 138 MPa (20,000 psi). 

The mechanical equipment used in room-and-pikar underground mining usuaky involves a series of specific operations with continuous mining equipment. Continuous miners use rotating heads equipped with bits to pick or cut through the coal without blasting and load it into a shuttle car for conveying to a belt system. 

Failure of power or controls to the valve (generally related to the seismic capacity of the cable trays, control room, and emergency power). These failure modes are analyzed as failures of separate systems linked to the equipment since they are not related to the specific piece of equipment (i.e., a motor-operated valve) and are common to all active equipment. 

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