Job Task Analysis
There are many forms or types of Job Task Analyses. An ergonomic Job Task Analysis (JTA) should include a detailed ergonomics profile of the workflow, the work tasks, and the steps of each task. If the focus of an analysis is the amount of work exposure over the course of an entire shift, the JTA should include the information listed above as well as the non-work activities that make up a typical shift in a given work setting so that the entire shift in minutes is accounted for in terms of tasks and activities (and even include breaks or rest periods).
An ergonomics-based JTA should also provide both an outline of the work flow in a shift and numeric data for each task that regularly occurs over the course of a typical shift. The numeric data for each task should be described in terms of physical demands and include the duration of each task, the forces required for each task, distances of the physical movement or handling of items related to each task and the repetitions or number of movements for each task. Physical demands should be described for both the whole-body and the upper extremities for each task that is included in the JTA.
Whole-body Vibration Analysis
Vibration data collection should be done in a "real setting" to most-accurately represent the ergonomic vibration exposures to an Operator of a machine, vehicle or other setting as per the methods section of the ISO 2631-1 standard. The WBV data collection should be done in the field and as the machine or item is in normal operation so as to include all relevant vibration events such as traveling in a machine or vehicle, sitting in the machine or vehicle as it idles and/or as is in "wait " mode and when the machine or device is in the "production mode" or the performance / purposeful phase of activity.
All of the elements listed above should be part of WBV testing as well as determinations of the duration of each of those individual and separate vibratory events. An ergonomics vibration analysis that does not include these elements is overlooking or missing vibration exposure whether it is intended or not.
Task Component Analysis
Task Component Analyses focus only on a single task. A single job task may have only one step which may take only a few seconds (for example, turn a valve) whereas some tasks have multiple steps and can take upwards of 30 minutes. Much like a JTA, the TCA includes the sequence of the steps of the task and each step of the task should include related physical demands in terms of amount of force, repetition, duration, movement/handling distance and other necessary information to fully describe the task.
Part of the use of TCAs and the building of an ongoing TCA list is that the list will finally include all tasks that typically occur in a given work setting. A relevant and specific list of TCAs can be combined so that a JTA (the tasks that occur over an entire shift) can be put together.