The Transport Accident Investigation Commission (TAIC) yesterday released two railway reports, finding rostered hours for train controllers had been excessive.

In potentially the most serious incident, at Otane, southwest of Hastings on January 18 last year, a head-on clash was only averted because the driver of an oncoming train noticed another train had been told it could go on the same track as his, TAIC found.

In that incident, a controller with 24 years' experience had told a freight train it could cross across the railway line on to another section of rail.

At the time, the controller was about 10 hours into a 12 hour shift, because of a staff shortage.

Also, in the four weeks before the crash, he had been called in to work on four of his seven rostered days off to cover shifts.

In another incident the same day further south at Woodville , TAIC found a different train controller was probably suffering from fatigue when he told a train it could "berth" on the maijl line at Makotuku, when another train had already been told it could "berth" at the same place.

The report said the controller's fatigue was probably "a result of the excessive number of late and night shifts he had worked in the six weeks leading up to the incidents".

In a third incident at Kokiri on the South Island's West Coast on February 3, TAIC found a train controller's fatigue after being called in to do extra shifts had probably caused him to allow a train into an area where contractors were working on the tracks.

But Maritime and Rail Transport Union general secretary Wayne Butson yesterday told NZPA he was satisfied Government track owner Ontrack was working to rectify controller rosters and limit fatigue.

"The main problem at the moment is there is a quite acute shortage of staff."

As long as that shortage continued, controllers would continue to need to cover for others who were sick, and would need to be called in on some rostered days off, Mr Butson said.

"Train controllers don't grow on trees basically - there is quite a long (training) lead in time and we live in a global market.

"With the renaissance of rail worldwide, New Zealand has become a very very good picking ground for overseas rail operators and companies to pick up highly trained, highly skilled staff, and our wages of course are languishing behind."

Australian wages for controllers, for example, were 30 per cent higher than in New Zealand.

Mr Butson did not believe the public were in any danger, despite TAIC finding the operators were fatigued.

"We're talking here about a highly professional, highly intelligent group of people.

"If they had any concerns about their own fitness for doing the job then I have no doubts whatsoever they would say `I'm not safe and I can't do it'."

TAIC has told Ontrack to limit night shifts for controllers, recruit enough staff to allow them to cover for sick days without calling in staff on rostered days off, and to allow a minimum 15 minute break when controllers are required to work past eight hours.

Ontrack has agreed to the recommendations, with the exception that it has said it does not yet know if it can manage the 15 minute breaks.