Root Cause — Information

Most companies have the requisite information technology in place to extend the enterprise the problem is they are not using it 

Previous chapters touched on the role of information and associated processes and systems. Chapter 25 described supply chain technology applications. Chapter 23 described the work of the Supply-Chain Council and the Council of Supply Chain Management Professionals (formerly CLM) in promoting supply chain process integration. Within the company. Section 16.3.3 described the S OP (Sales and Operations Planning) process for intermediate-term information exchange between operations and marketing. 

This chapter points to ways to use information to reduce supply chain costs and cycle times. James Morehouse points out that, for many, the tools are already available. How to use them for both operations and planning to extend the enterprise is the challenge. Examples of information of interest to supply chain operators and decision makers include  

Issues affecting the usefulness of information include accuracy, timeliness, 

We have pointed out that information sharing along the supply chain is difficult for many reasons. Inside the walls of a single company, department boundaries are barriers. S OP is an effort to overcome this barrier. The barriers are no less difficult across companies. Also, the traditional arm s length relationship between buyer and seller makes many reluctant to share information. Technologically, the means to share can also be difficult. The system at the supplier may not talk to the system at the buyer. 

Keith Kennedy of CGR Management Consultants describes the next level as proactive systems. It is these systems that offer ways to produce competitive advantage. Proactive systems use technology to push needed information to decision makers. Here we ll describe how proactive systems can improve the supply chain. 

In earlier sections, we stated that better competitive position comes from being different (Chapter 7). We described how to develop supply chains developed around the needs of a target market that would set you apart from 

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Incident Investigation Previous incidents related to the chemicals or equipment involved in the new toll should be considered during the PHA and must be considered if subject to PSM/RMP compliance. In addition, procedures should be in place to describe how the client will be informed and involved in the investigation. It is veiy important to ensure that action plans addressing the root cause of past incidents were implemented. 

If yes, for each incident, attach the incident report or give the following information Description of the incident, chronology of verifiable events, other pertinent facts, root causes and contributing factors, and proposals for corrective action. 

Error analysis techniques can be used in accident analysis to identify the events and contributory factors that led to an accident, to represent this information in a clear and simple manner and to suggest suitable error reduction strategies. This is achieved in practice by identification of the causal event sequence that led to the accident and the analysis of this sequence to identify the root causes of the system malfunction. A discussion of accident analysis techniques is included in Chapter 6. 

The types of data required for incident reporting and root cause analysis systems are specified. Data Collection practices in the CPI are described, and a detailed specification of the types of information needed for causal analyses is provided. 

For a major incident investigation using a comprehensive root cause analysis system, teams will be formed to acquire information relevant to determine the structure and analyze the causes in depth. In addition to evaluations of the immediate causes, imderlying causes are likely to be evaluated by investigations in areas such as safety and quality management. Both paper- and computer-based systems will be used to acquire and record information for subsequent detailed analyses. 

In the following sections, a number of methodologies for accident analysis will be presented. These focus primarily on the sequence and structure of an accident and the external causal factors involved. These methods provide valuable information for the interpretation process and the development of remedial measures. Because most of these techniques include a procedure for delineating the structure of an incident, and are therefore likely to be time consuming, they will usually be applied in the root cause analysis of incidents with severe consequences. 

In general, the value of a psychological perspective in incident analysis is that it directs the analyst to search for causes that would not otherwise have been considered. This means that the development of preventative strategies will be better informed. In addition, an evaluation of causes from a psychological perspective can be useful when the "root cause" appears to be an otherwise incomprehensible failure on the part of an individual. A psychological analysis can break the "causal log jam" by providing an explanation. 

Root cause 2 The informal method of shift changeover used on the plant meant that vital information relating to plant status was not communicated across shifts. 

This case study illustrates how the methodologies described in Chapter 6 can be used to analyze plant incidents and identify the root causes of the problems. Based on this information, specific error reduction strategies can be developed to prevent similar incidents from occurring in the future. Also, the findings of such an analysis can provide the basis for more general discussions about the prevalence of similar error inducing conditions in other plant areas. 

To gather information about the factors which contributed to the above incident, interviews were held with the workers and their management. Relevant documentation such as standard operating procedures and documentation relating to the incident was also collected. A task analysis (see Case Study 3) of the job of the top floor person was carried out in order to examine the operations involved and the factors which could affect job performance. Two techniques were used for the analysis of this incident, namely variation tree analysis and root cause analysis. 

Consider again a batch polymerization process where the process is characterized by the sequential execution of a number of steps that take place in the two reactors. These are steps such as initial reactor charge, titration, reaction initiation, polymerization, and transfer. Because much of the critical product quality information is available only at the end of a batch cycle, the data interpretation system has been designed for diagnosis at the end of a cycle. At the end of a particular run, the data are analyzed and the identification of any problems is translated into corrective actions that are implemented for the next cycle. The interpretations of interest include root causes having to do with process problems (e.g., contamination or transfer problems), equipment malfunctions (e.g., valve problems or instrument failures), and step execution problems (e.g., titration too fast or too much catalyst added). The output dimension of the process is large with more than 300 possible root causes. Additional detail on the diagnostic system can be found in Sravana (1994). 

The overall objective of the system is to map from three types of numeric input process data into, generally, one to three root causes out of the possible 300. The data available include numeric information from sensors, product-specific numeric information such as molecular weight and area under peak from gel permeation chromatography (GPC) analysis of the product, and additional information from the GPC in the form of variances in expected shapes of traces. The plant also uses univariate statistical methods for data analysis of numeric product information. 

Cause(s). If desired, the root causes of the failure mode should be identified. Identification of root causes provides information helpful for ranking hazards. 

Scenario A description of the events that result in an accident or incident. The description should contain information relevant to defining the root causes. 

EPA ARIP Responses to questionnaires sent by EPA from facilities that have had significant releases purpose is to learn about causes and consequences of hazardous material incidents 1986-Present Supplements NRC reports for more significant events Additional information on causal factors, consequences, and company safety programs Data are easily analyzed for common causes Includes all states and localities Survey relies on voluntary compliance Not comprehensive limited to select cases Checklist approach limits value of information to understand root cause Not designed to be a lessons-leamed database... 

The term cause within this section refers to inadequate process safety management practices. The causal information presented is not intended to be considered as root causes no consistent root cause analysis methods were identified within the data. 

With the plant interview information, verification of the data, and the completion of the simple calculations, an experienced troubleshooter will develop a set of hypotheses for the root cause of the defect. After the hypotheses are established, a series of experiments need to be developed that accept or reject the hypotheses. Once a hypothesis is accepted via experimentation, then the next step is to develop a technical solution to remove the defect. Often more than one technical solution Is possible. The best technical solution will depend on the cost and time to implement the solution, machine owner acceptance, and the risk associated with the modified process. An accepted hypothesis must drive the technical solution. If a hypothesis is not accepted prior to developing a technical solution, then the troubleshooter may be working on the wrong problem and the defect may not be eliminated from the process. 

Performance information for the incumbent resin was missing from the early parts of the decision-making process. The decision that the technical problem was the performance of the new resin was based on anecdotal information from plant personnel on the performance of the incumbent resin. That is, the plant personnel believed that the reject level for parts made from the incumbent resin was less than 5 %. A statistical analysis of the part defect rates was not performed. This lack of information early in the process allowed the plant manager to propose a poor technical solution without understanding the root cause for the defect. Later in the troubleshooting process, a statistical analysis of the defect rate indicated that the incumbent resin had a defect rate that was statistically equivalent to the new resin. 

This example clearly shows that developing and accepting a hypothesis based on accurate and complete information is necessary for setting an acceptable technical solution. If the plant manager could have persuaded the resin manufacturer to develop a new resin that was similar to the incumbent resin, then the defect would still be there, the cost of the troubleshooting process would have been extremely high, the supplier would have incurred unnecessary development costs, and a high level of defective parts would still have occurred because the root cause would not have been removed. 

Inspection of the barrel and screw for wear can provide information on the root cause for the wear. For example, if wear occurs at an axial location on only one side of the barrei and on all sides (angular direction) of the screw, then the likely root cause is that the barrel is out of alignment at that axial location. Conversely, if the barrei is worn on all sides and the screw is worn on only one side at the same axial location, then the root cause is likely a local bend in the screw. 

Several case studies are presented in the next sections that show some common root causes of contamination in injection-molded parts. In these case studies, the problem is presented in a manner that the troubleshooter would encounter during a trial or information-gathering session. In each case study, the modifications required to fix the process are detailed along with supporting fundamental information. Two of the case studies used (ET) screws to eliminate the defects. ET screws and other high-performance screws will be discussed in Chapter 14. 

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