Dr Karen McDonnell said that having a mentally-healthy workforce -- including positive working relationships -- is a key component of any successful organisation.
She was speaking at the start of Mental Health Awareness Week, which is organised by the Mental Health Foundation and runs until Sunday 22 May. The week is focusing on the value of positive relationships.
"Businesses not only benefit when their staff are physically healthy; but also when their staff are mentally healthy," said Dr McDonnell. "Positive feelings about work have been linked with higher productivity, profitability and customer and worker loyalty.
"On the flip side, poor stress management has a human, business and economic cost, leading to illness, absence and underperformance.
"Support and relationships are part of the HSE's six key areas for stress management standards. If an employee has good relations with those he or she works with, then they are more likely to be happy at work, feel supported in their role and able to be more productive."
The HSE recommends that organisations foster good working relationships by promoting positive cultures and not tolerating unacceptable behaviour. This includes tackling issues around workplace harassment and bullying and having proper grievance procedures and whistle-blowing arrangements in place.
The Mental Health Foundation said it chose to focus on relationships to help generate a wide understanding of their importance for people. IOSH has already spoken in support of this initiative and the foundation has planned a number of events during the week ahead.
The institution held a Parliamentary reception in February on the subject of mental health at work. It was hosted by Andrew Mitchell, MP for Sutton Coldfield, and was aimed at recently-elected MPs and new peers.