The Replacement of Propylene Filters - Assignment Example

Question 1(a). Elements of Good Procedure Researchers have continued to have conflicting opinions regarding what constitute elements of good procedure (Robert 2000). These views have often been different depending on the nature and complexity of industrial, laboratory or engineering procedures. However, there have been consensuses on some factors. Support person is one of the elements that have been agreed that define a good procedure. Different procedures including the replacement of propylene filters need a room where support person is needed in the procedure to provide assurances and quality control. Where necessary, for effective procedures, suggestions for implementation of hazards identified and evaluation processes indifferent to techniques should be considered. We consider this attribute an element essential for a good procedure because it helps in the successful review of hazards and flow of the procedure from the starting point to the end. Thirdly, change control defines the scope of a good procedure. It can be said that an engineering procedure is synonymous with change. In an engineering environment where elements such as replacement of propylene filters are concerned, every procedure should help people involved to modify what they plan to do when they enter laboratory or a factory. Fundamentally, this is what can be considered as change control. However, when the procedure allows for change control such change controls should be evaluated against the current hazard analysis to establish if the procedure will yield the same result or eliminate elements of risks associated with the change control. Strengths of Propylene Filter Replacement Procedure Provided The complexities of industrial and chemical procedures have necessitated the need to conceptualize what constitute elements of strong and weak procedure. This is the case in the understanding of liquid propylene or the procedure designed to replace propylene filter. To begin with, one of the elements of this procedure is that it has integrated the process that allows for the identification of hazards, enabling the user to carry the evaluation of the risks presented by the replacements of propylene filter. The ability to help users identify risks has been factored in the stage six (procedure six) where the procedure allows for the usage of rubber hose in the connection of the nitrogen cylinder regulator to the purge line nozzle. As Smith (1993) noted, industrial processes have changed and frequently involve a wide array of hazards and replacement of propylene filter is not different. Still on elements that make this procedure good, it provides the room for readers to understand and define the scope of work or procedure involved in the process of replacing the filter. An important, but often missed, in the preliminary step of replacement of the filter is the identification of the group tasks or task that is going to be evaluated from the first to the last step. Without the definition of such scope of work, the effectiveness of every subsequent step in the procedure can be compromised. In other words, without considerations of the scope of the procedure, critical skills or specific training requirements can be missed thus compromising the needed stages in the replacement of the filter. Hazard evaluation is another element that characterizes this procedure as strong. The product of hazard evaluation has been considered qualitatively---and to some extent, quantitatively. This makes it possible, considering stage 6, 7 and 9 for users to evaluate or assess the risks of the hazards of a given experiment; in this case primary safety engineering controls or safety devices in this case a chemical fume from nitrogen cylinder. Weakness of Propylene Filter Replacement Procedure Provided On the other hand, the procedure presented in annexe 1 has a number of weaknesses that are critical for the successful completion of propylene filter replacement. The first notable concern in the procedure is whether it will be possible to perform it within controls. To enumerate on this issue, it is essential that every procedure should be understood and that the controls placed in the procedure should be easily followed. In this case though, there are a number of concerns and questions that can be raised including “does the procedure warrant use of performance within controls to ensure all industrial or laboratory workers involved conceptualise the acceptable way to complete the process of filter replacement?” Looking at the procedure, particularly from step 4 through to step 8 there are further two critical weaknesses. First, the procedure fails to provide for administrative and engineering controls that are essential in the analysis and replacement. Secondly, there is not explanation or provision for a test to affirm functionality of all materials mentioned (bleed valve V4, valve V5, the cylinder regulator, cylinder store and the flange). Question 1(b). Hierarchical Task Analysis (HTA) on Propylene Filter Replacement With reference to propylene filter replacement we consider hierarchical task analysis (HTA) as systematic process of describing the hierarchical stages and sub-stages involved in the filter replacement. The intention of providing an elaborate HTA for propylene filter replacement is to ascertain the overall objective of the task. Looking at annexe 1 as provided, the stages 1-21 requires that HTA breaks down these components into different sub-tasks and these components provides clear guidelines, levels of descriptions and the scope of each task identified in a top-down manner. Studies have agreed that there are some concerns that should be given consideration when undertaking HTA (Kletz 1999). First, there is danger with propylene filter replacement and as such, HTA should consider whether the process filter out the needed information. Secondly, any process or procedure which cannot be represented in the 1-21 stages is considered non-data. To conceptualise these findings, we provide HTA for propylene filter replacement as follows: i. Processes of HTA task analysis for Propylene Filter Replacement Based on the stages/steps that have been provided in the annexe 1, we consider the HTA process in three distinct processes; starting of the procedure, stages of progression and finalization of the procedure. a. Analysis stage This stage involves the first four procedures as provided in the annexe 1 (Collect nitrogen cylinder from cylinder store, open filter bypass line V3, close in-line isolation valves V1 and V2 either side of the filter F1 and open bleed valve V4 and vent the filter body to the cold vent system). Looking at the first three stages, the HTA process involved will be the identification and specification of main tasks. Secondly, we are going to simplify the first four procedures into 5-9 subtasks. In order to conceptualise the purpose for simplification the HTA process describes them as objectives and this should cover the whole main task (from 1-21). Since the first four procedures are related, we have opined for the implementation procedures covering 1-4. Thirdly, we anticipate a number of set-backs as concerns the procedure provided. In order to work with any set-backs effectively the HTA processes will entail drawing of sub-tasks as a layer of different sub-procedures. These sub-tasks further provide for an avenue for understanding how different sub-tasks are linked to the main task. The progression analysis is another essential element needed in the understanding HTA for propylene filter replacement. Based on different levels that already exist, we make a decision on the level of detail such as general tasks to be performed, levels entailing keystroke among others. It is for this stage that one will be able to tell, through checked boxes, the task that should be continued. Additionally, the checked boxes will be number chronologically to help in following the process. The actual HTA is as follows: ii. Summary of Task Procedures Collection of nitrogen cylinder Opening V3 Close V1 and V2 Depressurisation as per gauge PI1 Connecting the nitrogen cylinder Opening V5 and the cylinder regulator Purge the filter Closing the nitrogen cylinder Detaching the rubber hose Closing V4 Unbolting the flanges Unbolting the flanges to the filter Removing the filter Replacing the filter and the refit Rebolting the flanges Rebolting the flanges to the filter Opening the V2 Opening V2 to bring the filter back Closing the filter bypass line V3 Return nitrogen cylinder to cylinder store iii. Preliminary Procedure The HTA to be undertaken will be based on the requirements of the operations above. With regard to the replacement of propylene filters, we have not been provided with information regarding the nature of the valves, nitrogen cylinder and rubber hose. However, we will develop the HTA assuming that the three materials adhere to standards of safer operations (CCPS 1992). Additionally, the goal of the operation is to replace the propylene filters therefore we are going to enumerate the Plan and Task by breaking down the tasks 1-21 until we reach “return nitrogen cylinder to cylinder store.” To conceptualise the tasks and sub-tasks within the framework of the procedure, we will be describing these section by a tag or name and allocating sub-tasks a number or alphabetical numbers unique to each tasks and sub-tasks. iv. Set Condition For the success of the replacement of propylene filters, there are two materials from the procedure that must be availed before the commencement of the process. These are: Rubber hose Connectors to the nitrogen cylinder Propylene filters Tasks Break-Down Analysis As opposed to the general principles for HTA, the overall aim of the analysis of propylene filter replacement is to derive a sub-goal hierarchy for the tasks under scrutiny. As we break down the goals and new operations emerge, sub-goals for every part of the procedure need to be identified. For this case, it is not the operations that are being investigated or analysed but their sub-goals. All of the lower level sub-goals have been broken logically to reflect the higher ones. We determine the goal hierarchy by assessing clusters of operations that belong together under the same goal. The HTA procedure will be broken down into different constituents and these breakdown will be termed as ‘sub-tasks’, which breaks down to attain a given goal. For instance, detaching the rubber hose and closing of valve V2 necessitate the next task or goal which we are unbolting the flanges and unbolting the flanges to the filter. As already noted, these tasks will be marked with numbers. These tasks when completed, will lead to achievement of a goal such as opening V2 to bring the filter back and closing filter bypass line V3. HTA Plan for Replacement of Propylene Filters The plan helps in the conceptualization of every process of HTA and the goal to be achieved in every task or sub-task. The plan elaborates on the simultaneous actions, parallel tasks and sub-tasks and sequences regarding how tree-braches in the HTA will be done. The end product or the final process of replacement as marked by code 21 marks the exit or the end of decomposition process in the HTA process and we consider this point where it will not be possible to breakdown the process of replacement of the filter further. Hierarchical Task Analysis for Propylene Filter Replacement Plan 0: Do 1, 2, 3, 4 in order Plan 4: Do 4.1 Plan 1.1 \ Plan 1.4.1: Do according to instructions then exit for 4.1.1-4.1.5 Plan 4.1.5: Do 4.1.6-4.1.13 and exit Read More