How to Recognize that a Worker May Be Suffering from a Mental Illness


Employers have a duty to accommodate disabled workers, which includes accommodating those with not only physical but also mental disabilities. (Use this form to gather information to help you properly accommodate a disabled worker.)

The burden is on workers to request an accommodation if they believe they need one. But because of the stigma attached to mental illness, a worker with a mental disability may be reluctant to ask for an accommodation or any help at all.

So it’s in the best interests of workers and employers for manager and supervisors to be aware of the signs that someone might be suffering from a mental illness in order to reach out to that individual and see if he or she needs assistance or an accommodation.

According to Mental Health Works, mental illness includes a broad range of symptoms and behaviours, and it’s not easy to determine whether someone is mentally ill. One key indicator is that someone may begin to act uncharacteristically—for example, an energetic person may seem lethargic for a considerable time.

Note that some behaviour changes may reflect that a worker is having short-term personal difficulties, such as the breakup of a relationship, or just a bad day. Focus on a pattern that continues for a longer period and changes that suggest the person’s experiencing a mental health problem that goes beyond being “stressed out.”

Some of the warning signs that can indicate that a person has a mental health problem include:

  • Consistent late arrivals or frequent absences
  • Lack of cooperation or a general inability to work with co-workers
  • Decreased productivity
  • Increased safety incidents or problems
  • Frequent complaints of fatigue or unexplained pains
  • Difficulty concentrating, making decisions or remembering things
  • Making excuses for missed deadlines or poor work
  • Decreased interest or involvement in one’s work
  • Working excessive overtime over a prolonged period of time
  • Expressions of strange or grandiose ideas
  • Displays of anger or blaming of others.

If you observe any of the above behaviour, talking to the employee privately in the context of his or her job performance may help you determine whether mental health is a factor. You may then be able to encourage the individual to get help and/or request appropriate accommodation.

For details on specific mental health problems, including symptoms, go to the Canadian Mental Health Association’s website. And for more information, resources and tools on mental health and psychological safety in the workplace, go to the OHS Insider’s Psychological Safety Compliance Centre.