About 200 adventure tourism companies are still waiting to get final safety approval before new rules take effect in just over a week.
The companies have until the end of the month to complete a safety audit process.
So far, eleven written warnings had been issued to companies.
Worksafe NZ chief executive Gordon MacDonald said it was a tight timeframe but most of those still waiting for approval had started the process.
He said operators who were not audited by 1 December would have to stop trading until they complied.
"We are confident that a lot of those are right at the end of the process and they've gone through their documentary audits, they've gone through their field audits.
"The majority of those operators will get across the line by the 1st of December."