It is common for safety professionals to be involved in decisions related to an employee's ability to work safely and effectively, either because of concerns that he/she could be at work but is not, or because the employee is at work but may be impaired and creating unacceptable risks. Such decisions can be difficult and stressful for all involved, as they are inherently conflictual. In addition to the specialized concerns peculiar to a given workplace, there are general considerations about being aware of Fitness-for-Duty issues, and how to deal with these issues that are applicable to all employment, with particular aspects imparted by details of the specific workplace itself.
How do we usually know if an employee is fit for duty or not? In two ways: by the employee's own statements and actions (such as showing up for work), and by observation of actual workplace performance and behavior. In a "routine" work situation, an employee's stated belief is consistent with reality, as to whether the worker is able to work effectively and safely. That is, either the employee says he/ she can work, and is correct; or correctly states that an injury or illness prevents work without making accommodations. We can think of those two situations as the "sweet spots" where no further analysis is due.
On either side of that match of statement and reality are two unhappy extremes, when the employee's self-determination does not match other observations. Then conflict arises because of the need to avoid undue risk of harm while maximizing productivity. These two driving forces, as indicated in Exhibit 1., may appear to be in opposition when an employee wishes to work but is either unproductive or risks actual harm; or on the contrary, when an employee wishes not to work but is actually able to do so.
Exhibit 1. This matrix demonstrates the match or mismatch between an employee's statement of ability and reality (available in full paper).
In the white, "routine" squares, the employee correctly presents a work status as being able to do the job safely and effectively. In the other two squares, there is a mismatch between perception and reality. In the square labeled, "Needless Work Disability," the mismatch would, absent further investigation, keep an employee from work when in fact this could be avoided. In the square labeled, "Unacceptable Risk of Harm," allowing the employee to perform certain tasks could put people or property at risk, or at least allow unacceptable levels of inefficiency or counterproductive activity.