WorkSafe is probing complaints that Wellington cafe Prefab is not checking Covid-19 vaccine passes.
A WorkSafe spokesman confirmed the regulator has received notifications of concerns and was "looking into them".
Prefab Eatery, the 180-seat flagship cafe for the ACME brand, was founded in 2013 by Jeff Kennedy and Bridget Dunn.
Under the Covid-19 traffic light system at orange, hospitality businesses can only open for takeaways if they do not follow vaccine pass requirements.
According to WorkSafe, there have been 226 reports of possible breaches of Covid-19 orders in the Wellington region since December last year.
These include issues around face mask use, physical distancing requirements, QR code compliance, and My Vaccine Pass requirements.
Prefab has been approached for comment.
The concerns come as the cafe has reopened to provide both a breakfast and lunch offering.
This is after it abruptly shut its doors in September. Staff were informed that all positions at Prefab cafe would be made redundant in a letter sent by Dunn and Kennedy, which the Herald has seen.
Dunn and Kennedy said in the letter they knew the decision would not be easy for staff.
"But this was an inevitable outcome of this global crisis and we believe this will be the best for the business. Therefore, regretfully all the positions at Prefab cafe will be redundant.
"This was a very hard decision to make. We would like to thank you for your hard work and commitment to Prefab Cafe."
They then went on to say publicly that the rules made it "impossible" for them to open responsibly.
"A cafe is a space where people eat, drink, talk, have meetings, cook, serve, clean, wash, prepare food. It is a perfect storm for spreading aerosols causing infection."
But as early as October, Dunn confirmed to the Herald the opening of a Prefab coffee bar from 7am to midday only, Monday to Friday.
It's understood some former Prefab employees found jobs elsewhere in Wellington's hospitality industry.
Dunn did not respond to questions about why Prefab had chosen to open a coffee bar or whether any staff who were made redundant had been employed again.
Now the cafe is also open for lunch, offering a much more extensive menu.