Task analysis purpose

The applied purpose of the task analysis has the greatest impact on what type of data are needed. Applications of task analysis vary greatly and include decisions that may or may not involve machines. 

A task can be viewed as a sequence of actions performed to accompHsh one or more desired objectives. Task analysis and decomposition involve breaking down a task into identifiable elements or steps and analyzing them to determine the resources (human, equipment, and environmental) necessary for the accomplishment of the task. As indicated in earlier chapters, aU human tasks require the interaction of mental and physical resources, but it is often convenient, for analytical purposes, to make a distinction between tasks that require predominantly physical resources of the person performing the tasks and tasks that require predominantly mental resources. These different types of tasks are often analyzed separately. Usually, in physical tasks, the mental requirements are described but are not analyzed as meticulously as the physical requirements. For example, a heavy-hfting task in industry requires musculoskeletal strength and endurance, decision making, and other resources, but the successful completion of such a task is... 

To date, there is no reliable quantitative model that can combine mental and physical resources. A general-purpose task-analysis method that uses active links between the various compartments of... 

FIGURE 81.1 The user s purpose is served by the application task, which is accomplished through the interaction task. 81.4.1.5 Task Analysis, Allocation, and Modeling... 

The purpose of a Job Task Analysis (JTA) is to analyze some particular action in depth, so that effective procedures for that job can be written. Typically, JTA has been used most in high hazard industries, such as the operation of nuclear power facilities. 

In Management Guide to Loss Control, by Frank E. Bird, Jr., a chapter on Proper Job Analysis and Procedures extends the purposes of a task analysis to include aspects other than safety. Bird said ... 

A great help in the goal of analyzing all the possible deviations is the availability of further documentation as accident analysis or audit reports. It is always better to try to obtain multiple sources of information and different points of view for developing the task analysis. If the different points of view lead to different task paths it wiU then be required to make a hypothesis about which one is the most reliable one, or if they are equally valid. There is no rule for deciding at what level of granularity the task analysis should arrive. The decision depends mainly on the purpose of the study. 

The job safety analysis (JSA) [also referred to as the job hazard analysis (JHA)], which is a more simplified form of task analysis, has been a longstanding tool for task and function analysis. JSA has been available and utilized in general industry for many years by the industrial safety community. However, many practitioners do not understand or are simply unfamiliar with the connection between the JSA and the system safety tasks of hazard identification and analysis. It has even been suggested by some in the profession that the JSA itself is a type of oversimplified system safety analysis and, if performed earlier in the job development phase, could be used as the basis of a preliminary hazard analysis for a specific task or set of tasks. However, because JSA is often (if improperly) used to analyze a function only after it has been implemented, much of the data is not factored into the system safety process. The primary purpose of the JSA is to uncover inherent or potential hazards that may be encountered in the work environment. This basic definition is not unlike that previously discussed regarding the various system safety analyses. The primary difference between the two is subtle but important and is found in the end-use purpose of the JSA. Once the job or task is completed, the JSA is usually used as an effective tool for training and orienting the new employee into the work environment. The JSA presents a verbal picture of a specific job. 

Job analysis for training purposes involves a careful study of job tasks. This is a further effort to define the specific content of training—determining what should be the contents of training in terms of what an employee must do to perform a task, job, or assignment in an effective way [4]. It requires an orderly, systematic collection of data (task analysis) about the job. We are familiar with this through our job Hazard Analysis procedures. Refer to Chapter 15 for an overview of Job Hazard Analysis. The following methods are also available for job analysis ... 

The basic purpose of task analysis is to systematically describe and analyze activities and document the procedures, processes, and resources that are used by individuals or groups to achieve the target/goal. Task analysis deals with a variety of human factots, so for HAZID and PHA the aim is to assess the human error or chances of human error and try to reduce that effect. 

When the operator interface involves a visual display unit, attention should be paid in the design to adequate response times, navigation and help facilities [2, 3]. Every display field should be used for one purpose only in a given mode and context. For instance, the use of a single field to display the values of the same parameter in diflerent engineering units should be avoided. All interfaces should be consistent and should use the same names and identifiers. A task analysis should be performed to demonstrate the adequacy of the manual safely provisions and aity associated displayed information. 

For error analysis purposes, human error identification (HEI) approaches such as SHERPA (Embrey, 1986) can be used see Chapter 14 for a full description of SHERPA. SHERPA uses a behavioral taxonomy linked to an error mode taxonomy and is applied to an HTA of the task under analysis. The behavioral and external... 

Task Analysis for Error Identification was developed to allow errors to be predicted, but in this context it can serve as a useful way of modeling the interaction between user and the system together, rather than separately. TAEEI assumes that people use systems in a purposeful manner, such that the interaction may be described as a cooperative endeavor. The technique makes the further assumption that actions are constrained by the state of the system at any particular point in the interaction and that the system offers information to the user about its functionality. 

In this cross-sectional study, permit to works system procedure in a petrochemical plant were studied for potential human errors. For this purpose, in the first stage occupational tasks in P.T.W procedure were analyzed using Hierarchal Task Analysis (HTA) (Stanton 2004). 

Develop profiles of jobs considered suitable for early-return participants. A profile should define the job in terms of overall physical demands, motions required, environmental conditions, the number of times the job is performed per week, and its duration. Conduct a systematic analysis of specific jobs for the purpose of modifying them to accommodate the unique needs of the injured worker. Individuals who are skilled in ergonomic task analysis, engineering, safety, and biomechanics should help perform the job analysis. Managed-care providers can also assist in job modifications. Communicate the availability of early-return jobs with care providers, claims adjusters, and the injured worker. Work with your managed-care provider and worker to move them to full production status in their assigned jobs as quickly as possible. 

---