An asbestos remover has been suspended over a job done in the Auckland suburb of Parnell.
About 220 people die each year from preventable asbestos-related disease.
WorkSafe said it was notified on 29 February about the Parnell job and suspended the licence of Shamrock Reroofing.
It also issued an improvement notice to take action by 3 April.
"The notice requires the business to have an effective process in place to identify and manage the risks of asbestos in relation to refurbishment roof work on the site," it said.
RNZ has approached the company for comment.
WorkSafe is also assessing a second site in Auckland, in Avondale, for possible asbestos contamination by a different removalist.
The agency visited the site in mid-February but said it still does not have enough information to gauge if there was contamination.
"WorkSafe is not investigating this incident, but is continuing our assessment."