The ban on the use of Robinson helicopters has grown with Fire and Emergency joining the Department of Conservation in deciding not to use them.
Robinson models, R22, R44 and R66, are on the Transport Accident Investigation Commission watchlist, and in February this year, DOC pulled them from use.
The Robinson helicopters have featured in 143 crashes in New Zealand since 2000 - 21 of which were fatal.
The Civil Aviation Authority have also investigated 14 fatal crashes caused by mast bumping.
That's contact between an inner part of a main helicopter blade and the main rotor drive shaft, which usually results in the machine breaking up in flight.
Fire and Emergency said there's been no explanation to ease concerns over mast bumping.
Fire and Emergency's National Manager of Rural Operations John Rasmussen said the ban is due to the risk of using the helicopters in turbulent conditions - and it will remain in place while the machines are on the watchlist.
"Fire fighting, particularly aerial fire fighting, is quite often undertaken in turbulent conditions - that's both because of terrain, the fires themselves and quite often in high wind conditions which are conditions which I guess are similar to those Robinson Helicopters experience that mast-bumping type problem," Mr Rasmussen said.
While it hasn't used Robinsons recently - the ban ensures they won't in future, he said.
"We're usually going for bigger, more robust helicopters that can lift quantities of water and are able to transport personel, so I guess this is more of an operational instruction to ensure this doesn't happen," he said.