Process controls human observation

Cognitive type This contemporary technique is used for supervisory control and decision making. Here, the focus is on the mental process behind human observable behavior in decision making or problem solving. This also forms part of HRA. 

The most utilized and reliable process control in the petrofeum and related industries is human observation and surveillance. Local pressure and level gages along with control room instrumentation are provided so that human observation and actions can occur to maintain the proper process conditions. First stage process alarms are provided to alert operators to conditions that they may not have already noticed. Typically when secondary alarm stages are reached, computer control systems employed to automatically implement remedial actions to the process. 

Human beings provide the first line of observation and defense for any facility. Periodic or constant first hand operator on site surveillance of the process provides careful observation and reporting of all activities within the facility. Humans have keen senses that have yet to be expertly duplicated by instrumentation devices or sophisticated technical surveillance mechanisms. In this fashion they are more valuable in the observation of system performance than ordinary process control systems may be. 

Basic Process Control System (BPCS) - Pneumatic, electronic, hydraulic or programmable instruments and mechanisms that monitor and/or operate a facility or system to achieve a desired function, i.e., flow control, temperature measurement, etc., which are supervised by human observation. 

The undelayed evaluation of state of a culture by using software sensors and computers, based on the quantitative analytical information provided by hardware sensors and intelligent analytical subsystems, constitutes an excellent basis for targeted process control. Experts - either human or computer - have the data and the deterministic knowledge to trace observed behavior back to the physical, chemical and physiological roots thereby gaining a qualitative improvement of bioprocess control, a quantum leap process control can act on the causes of effects rather than just cure symptoms. A simple standard operating procedure [398] has proven useful, namely ... 

The primary safeguards for any facility is usually considered human observation, either physically at the plant or from instrumentation in a control room. API RP 14C provides typical process safeguards (instrumentation, alarms and shutdowns) usually employed in the petrochemical industries. 

The third concept used in STAMP, along with safety constraints and hierarchical safety control structures, is process models. Process models are an important part of control theory. The four conditions required to control a process are described in chapter 3. The first is a goal, which in STAMP is the safety constraints that must be enforced by each controller in the hierarchical safety control structure. The action condition is implemented in the (downward) control channels and the observability condition is embodied in the (upward) feedback or measuring channels. The final condition is the model condition Any controller—human or automated-needs a model of the process being controlled to control it effectively (figure 4.6). 

The word sensor typically refers to a device that converts a change in a physical stimulus into output parameters that can be read by human or an electrOTiic instrument As an example, a thermocouple that converts the difference in temperature at a reference point and the measurement point into an electrical voltage forms a temperature sensor. The output of a sensor contains information about the state of a physical object (e.g., a machine tool) or a process (e.g., metal forming). Such information can be processed for improved observability in manufacturing machines and processes (Domfeld 1992 Altintas and Park 2004 Gao et al. 2008 Altintas and Jin 2011), leading to better control and decision-making (Toenshoff and Inasaki 2000). 

Variation is the fluctuations that can occur based on inconsistent environmental, human actions, equipment, tools, etc. Fluctuations of injuries and behaviors occur due to these variations in actions and conditions in the workplace. The statistical process control (SPC) (used in quality management) can aid in the review of injuries and observations, the organization can show the variations in its system. The SPC show whether the system is out of control and needs specific issues addressed or if it is in control but requires major across the broad safety program improvements (Daniels and Daniels, 2004 Deming, 1986). 

Operator has to observe the process more frequently as a result of nonsteady state operating conditions. This requires more frequent control interventions, leading to an increased potential for human error. 

The following techniques can be used to collect data about human performance in CPI tasks and provide input to task analysis methods described in Section 4.3. These data can include process information critical for the task, control strategies used by the workers, diagnostic plans etc. A distinction can be made among data collection methods that provide qualitative data (such as interviews, observations, and sources of documentation) and methods that can be used to measure aspects of performance (such as activity analysis, simulations, and information withholding). The latter methods can provide more precise data which can be quantified. 

The overall evidence from studies in animals supports the observations of lead neurobehavioral effects in humans. As pointed out by Cory-Slechta (1995), studies in animals have provided a direct measurement of the behavioral process per se, and have done so in the absence of the covariates (e.g., socioeconomic status, parental IQ) known to affect IQ scores in human studies. It is also worth noting that animal studies, in which the experimental design is carefully controlled, have shown that the timing of exposure is crucial, that different neurobehavioral outcomes are affected differently (different thresholds), and that some behavioral alterations last longer than others. 

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