September 2018 Newsletter:

Nothing More Essential in a JDA than Essential Duties

Job Demands Assessment

A Job Demands Assessment (JDA) is an objective document designed to describe the essential (and maybe non-essential) functions of a job or task, including the physical, cognitive, and environmental requirements.


Information is collected through interviews with employees and Supervisors/Managers, observation, gathering of objective measurements (e.g. weights/forces, heights, reaches), and completing time studies for postures to develop an objective picture of what the job requires.

As the title implies, one of the most important parts of a JDA is the Essential Duties section.

What is an Essential Duty?

An essential duty is any requirement of a job that is entirely necessary; without it, the job or job task would be incomplete. In determining this, it is best to consider these 3 questions:

  1. Why does the job function exist?
  2. Does the employee actually perform this job function?
  3. Would the overall purpose of the job be accomplished if this task was not performed?

If the answer is yes to all 3, the job function should be considered absolutely essential to the position.

Why do you need to list the Essential Duties in the JDA?

The Essential Duties section provides an overview of how much time is spent on each of the essential job functions required of the position/task. As a result, it drives much of the other data generated within the remainder of the document and will impact your ability to accommodate an employee back into the job, or not.

For example, assume you have a lifting restriction of 20 lb. If lifting greater than 20 lb. only occurs in an essential duty that occurs for 0.5 hours/day then the odds of this being something that can be accommodated out of this job is good. However, if it occurs in an essential duty that happens for 4 hours/day the odds are much less.

This is also particularly important in the CDA section as you cannot use a stopwatch to calculate how much time someone spends using their memory to perform tasks. Instead, the best approach is to connect the cognitive requirements of the job to their Essential Duty, which ultimately provides a duration of time that your employee may be performing that task.

Evaluate your JDA

To fully understand the benefits of a JDA, we need to understand the different roles it plays in the return to work process and the importance of objectivity. Without accurately documented job demands, various difficulties may result: (a) a doctor may be limited in their ability to determine an employee’s work restrictions for return to work, (b) a physiotherapist or other rehab professional may experience difficulty in accurately preparing the employee for returning to work and (c) you, as the employer, may experience difficulty with ensuring a safe and healthy return to full duties.

Ensure your JDA meets your needs and industry expectations. Firstly, it should document all MSD hazards including force, postures, repetition, vibration, contact stress, and more! It should also have a thorough and detailed essential duties section that accurately breaks down the job.

A sound JDA is worth its weight in gold to ensure a safe and happy workforce.

Click here to view our PDA and CDA service page to learn more about this essential return to work tool.

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