A speaker at the recent Health in Construction Leadership Group Forum stood on stage and said: “I unclipped my harness and walked to the edge and thought the world would be better without me”. The room fell silent. Leaders were uncomfortable. Questions followed: what could the employer have done?

Some of us may have been involved in cases where no one can explain the actions of the trained and experienced worker who died. The employer knows of the requirement to ensure health and safety, but often the investigation begins with blame, remorse and the assumption the employer must have caused the death.

There is rarely evidence of suicide – with the exception of Telecom France, when 24 employees took their lives over seven years. The majority left letters blaming pressure from management.

Many of us will also remember the story of Jacintha Saldanha, the nurse who committed suicide after she allowed Kate Middleton to be contacted by radio DJs in a prank call. The pressure fell on one individual, and her death should have been predictable.

Recent research by Oxford and Stockholm universities found people who know a work colleague who died by suicide are three times more likely to follow suit. It’s evidence that suicide is now a workplace risk. But how can you manage depression when you don’t know colleagues are suffering? Even if we carry out pre-employment questionnaires or health surveillance, staff don’t admit to mental illness through fear of stigma, job security or because they cannot diagnose their own mood.

However, doing nothing is not the answer. Suicide is the most common cause of death for men aged between 20–49 in England and Wales, according to 2015 figures from the Office of National Statistics. Three quarters of the population with a diagnosable mental illness receive no treatment.

Tonja Schmidt, Head of Development and Evaluation at the Samaritans, says that stigma persists simply because we don’t have the words to express our feelings about it. There’s a degree of pressure to ‘be seen to be coping’ and not showing personal emotions, and if we do see the signs among colleagues we don’t know how to respond.

Through training and authentic caring the evidence suggests people can be helped. The speaker who contemplated taking his life by jumping from height underwent cognitive behavioural therapy, which has saved his life.

As well as the moral duty, there is a business case for taking the time to care: mental illness is responsible for 91 million working days lost and costs £30 billion each year. Remember: if one person talks, the other needs to listen.

When dealing with employees suffering with depression, it’s important to remember that making one suicide attempt doesn’t mean a colleague won’t make another – those who have attempted suicide are 100 times more likely than the general population to do it again. But talking to a colleague about suicide won’t prompt them to do it – raising the issue of suicide gives them permission to talk about their feelings and allows them to discover options other than ending their life.

Colleagues who threaten suicide are not attention seekers. Their feelings must always be taken seriously and your compassionate response could be vital to their recovery. Colleagues who are suicidal don’t necessarily want to die. They simply don’t want to live the life they have.

You don’t have to be mentally ill to consider suicide. Despair or hopelessness are also key factors in the decision to take a life. If an employee is serious about suicide you can still help them. Suicidal feelings can be temporary and timely support helps reduce the risk of them dying by suicide.

Along with the suite of measures Prime Minister Theresa May announced recently in a bid to tackle mental health in the workplace, IIRSM will work with its members to transform the way we deal with mental illness.