Action corrective

The "feedback loop in the analytical approach is maintained by a quality assurance program (Figure 15.1), whose objective is to control systematic and random sources of error.The underlying assumption of a quality assurance program is that results obtained when an analytical system is in statistical control are free of bias and are characterized by well-defined confidence intervals. When used properly, a quality assurance program identifies the practices necessary to bring a system into statistical control, allows us to determine if the system remains in statistical control, and suggests a course of corrective action when the system has fallen out of statistical control. 

The goals of quality assessment are to determine when a system has reached a state of statistical control to detect when the system has moved out of statistical control and, if possible, to suggest why a loss of statistical control has occurred so that corrective actions can be taken. For convenience, the methods of quality assessment are divided into two categories internal methods that are coordinated within the laboratory and external methods for which an outside agency or individual is responsible. The incorporation of these methods into a quaKty assurance program is covered in Section 15C. 

With a prescriptive approach to quality assessment, duplicate samples, blanks, standards, and spike recoveries are measured following a specific protocol. The result for each analysis is then compared with a single predetermined limit. If this limit is exceeded, an appropriate corrective action is taken. Prescriptive approaches to quality assurance are common for programs and laboratories subject to federal regulation. For example, the Food and Drug Administration (FDA) specifies quality assurance practices that must be followed by laboratories analyzing products regulated by the FDA. 

Ton-exchange resins are used repeatedly in a cyclic manner over many years, and deterioration of both physical and chemical properties can be anticipated. Comparison of the properties of used resin with those of new resin is helpfiil to learning more about the nature and cause of deterioration (12). Corrective action frequendy extends the life of the resin. Comparison of properties must always be made with the resin in the same ionic form. 

This hst of basic items covered ia a mock OSHA iaspection appear to be obvious items that any faciUty should observe. However, nearly every safety or fire iaspection uncovers these items duriag iaspections, causiag the faciUty to receive fines or warnings because maintenance people do not perform their own regular and thorough iaspections of their faciUties to avoid corrective actions by code enforcing agencies. 

Static reliability models are used in preliminary analyses to determine necessary reliability levels for subsystems and components. A subsystem is a particular low level grouping of components. Some trial and error is usually necessary to obtain reasonable groupings for any particular system. Early identification of potential system weaknesses facilitates corrective action. 

Establish Corrective Action. Corrective actions should be clearly defined beforehand, with the responsibiUty for action assigned to an individual. 

A technique called probabiUstic safety assessment (PSA) has been developed to analy2e complex systems and to aid in assuring safe nuclear power plant operation. PSA, which had its origin in a project sponsored by the U.S. Atomic Energy Commission, is a formali2ed identification of potential events and consequences lea ding to an estimate of risk of accident. Discovery of weaknesses in the plant allows for corrective action. 

Corrective action should be initiated when value is > — 0.23 V against the standard hydrogen electrode (SHE). Plant-specific values should be estabUshed for protection of stainless steels and nickel-based critical components. 

The main disadvantage of the feedback control strategy is that no corrective action is taken until after a deviation between the measured controlled... 

The primary advantage of the feedforward over the feedback control strategy is that corrective action is initiated before the controlled variable is upset. Feedforward control, however, has its own drawbacks, ie, variables used to characterize the disturbances must be measurable a model of the response of the controlled variable to the disturbance must be available (when the feedforward strategy is used alone, the control performance depends on the accuracy of the model) and the feedforward control strategy does not compensate for any disturbance not measured or modeled. 

Customer Complaints. A failure in a company s quaUty system often shows up in the form of a customer complaint. These reports of nonconformances, whether for product or service deficiencies, are typically received by the sales or customer service organization and then channeled to QA. Quahty assurance often tracks the progress and coordinates the complaint investigation. Once completed, it is QA that reviews the report of the investigation and corrective action for thoroughness and efficacy. QuaUty assurance then either passes the information along to the sales or customer service organization or contacts the customer direcdy. 

U.S. EPA. Assessing UST Corrective Action Technologies Early Screening of Cleanup Technologies for the Saturated Zone, EPA/600/2-90/027, prepared by P. J. Reidy and co-workers, U.S. Environmental Protection Agency, Washington, D.C., 1990. 

The extent of chemical and physical interactions among the components of a dmg dehvery system are characterized. Changes in chemical composition can be detected by analytical methodologies. The dmg formulation and the occurrence of byproducts need to be identified. Physical changes, such as swelling and delamination, also need to be identified so that corrective actions can be taken. 

The second law can also suggest appropriate corrective action. Eor example, in combustion, preheating the air or firing at high pressure in a gas turbine, as is done for an ethylene (qv) cracking furnace, improves energy efficiency by reducing the lost work of combustion (Eig. 4). 

Does not require identification and measurement of any disturbance for corrective action Control action not taken until the effect of the disturbance has been felt by the system... 

Transmission of more than one value from a transmitter. Information beyond the measured variable is available from the smart transmitter. For example, a smart pressure transmitter can also report the temperature within its housing. Knowing that this temperature is above normal values permits corrective action to be taken before the device fails. Such information is especially important during the initial commissioning of a plant. 

Regulators may be used in gas blanketing systems to maintain a protective environment above anv liquid stored in a tank or vessel as the liquid is pumped out. When the temperature of the vessel is suddenly cooled, the regulator maintains the tank pressure and protects the waUs of the tank from possible collapse. Regulators are known for their fast dynamic response. The absence of time delay that often comes with more sophisticated control systems makes the regulator useful in applications requiring fast corrective action. 

Actual progress made with construction work can be indicated on the bar chart by filhng in the open bars according to the percentage toward completion. Comparison of the actual progress bar for the whole project with the cumulative labor-hour curve indicates whether the job is ahead of schedule or not. If corrective action is required, effort should be concentrated on the key or critical items. 

As the mechanical integrity of the pump system changes, the amplitude of vibration levels change. In some cases, in order to identify the source of vibration, pump speed may have to be varied, as these problems are frequency- or resonance-dependent. Pump impeller imbalance and cavitation are related to this category. Table 10-11 classifies different types of pump-related problems, their possible causes and corrective actions. 

HAZOP (Knowlton, 1989 Lees, 1980 CPQRA, 1989, pp. 419-422). HAZOP stands for hazard and operability studies. This is a set of formal hazard identification and elimination procedures designed to identify hazards to people, process plants, and the environment. The techniques aim to stimulate in a systematic way the imagination of designers and people who operate plants or eqmpment so they can identify potenti hazards. In effect, HAZOP studies make the assumption that a hazard or operating problem can arise when there is a deviation from the design or operating intention. Corrective actions can then be made before a real accident occurs. 

Monitoring, fault diagnosis, and implementing corrective actions... 

Interlock System A system that detects out-of-limits or abnormal conditions or improper sequences and either halts further action or starts corrective action. 

As follow up, document the implementation of corrective actions taken by the toller. Keep this documentation with the initial inspection report that lists the deficiencies for which actions were taken. 

Once the successful bidder is selected, it is still possible to request corrective actions and additional terms through contract negotiation. There are occasionally situations where a contractual term cannot be negotiated with the first selection and the next candidate is offered the toll contract. Chapter 3, Mutual Agreements, Obligations, and Contract Considerations addresses this topic in more detail. 

Good The management systems audited provided reasonable protection against significant loss or noncompliance with regulations and directives. Any deficiencies found were deemed minor. Relevant management systems are documented and routinely followed. Some corrective action may be necessary. 

Needs Significant Improvement There are no management systems or those audited provided little or no protection from significant loss or noncompliance. Urgent corrective action is required. Additional auditing/investigation is required. 

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