The union for supermarket workers is calling on Countdown to put significant support in place to help staff affected by yesterday's terrorist attack

First Union's Tali Williams says support for workers was good after a man attacked shoppers in Dunedin earlier this year.

She said people had access to discretionary leave to seek help, because it's a very traumatising thing.

She says once the New Lynn store is up and running again, workers will want to see around-the-clock security staff and police presence in place to make them feel safe.