Paul Longley, the founder of Think Mental Health, a training provider that took park, said breaking the record on 10 October was a “proud moment”.
“When we come together to talk about mental health, we break down barriers and show that no one has to face their struggles alone,” he added.
Students from the college were also involved, alongside staff from Smith & Nephew, the medical technology company, and Think Cloud, an IT support firm.
Employees joined the call from offices around the world, including the US, Canada, Mexico, Costa Rica, India, Italy, Germany and China.
There were 916 verified participants, with more than 1,400 involved at one point, surpassing the previous record of 770. Organisers said it offered a “shared moment of reflection, learning, and conversation”.