Mechanical defects were involved in 2.5 per cent of all accidents and such defects were the sole cause of less than 1 per cent of all accidents, Mr Stockdale said.
The changes include:
* new cars will have an initial inspection but no further WOF check will be required until the vehicle is three years old. After that, they will require annual inspections.
* vehicles which are more than three years old and first registered after 1 January 2000 will require annual inspections.
* older vehicles which were first registered before 1 January 2000 will still require 6-monthly checks.
Mr Bridges said the mix recognised concerns about older vehicles on the road, while also recognising that in new cars, the quality and safety features had improved over time and the six-monthly checks were unnecessary.
He said the Ministry of Transport had calculated that the changes would save motorists and businesses $159 million a year - or $1.8 billion over 30 years - including savings in inspection costs, law enforcement costs - such as fines for unwarranted vehicles - and the time spent getting a WOF.
Euan Philpot, chief executive of JEVIC NZ Limited which is set to take over VINZ, also supported the changes, saying they would reduce costs, increase competition and create opportunities for vehicle inspection companies to develop new services.
During the reform process there will be some disruption to the inspection industry for up to 24 months, he said.
There will also be changes for the Certificate of Fitness regime which applies to transport vehicles such as taxis and rental cars. Although the default position will be to retain six-monthly checks, the Transport Agency will have a discretion to require individual operators to undergo either more or less regular checks, between every three months to a year. That will depend on the operators' safety records. That change is expected to save between $14 million to $41 million a year.
To help address concerns raised about less frequent warrant checks, Mr Bridges said money would be put into public education campaigns and more funding for Police enforcement on warrants.
He said the changes brought New Zealand into line with other countries.
"New Zealand currently has one of the highest inspection frequencies in the world.''
He said NZTA was also reviewing the annual car licensing (registration) system, looking at ways to make paying the fee easier and reduce infringement notices by using more reminders and payment incentives such as late payment penalties.
The Motor Trade Association (MTA) said the changes would mean the loss of more than 2000 jobs because fewer inspections would need to be carried out, pushing more skilled people out of the automotive industry.
Furthermore, it would increase risks to motorists and ultimately be more expensive for them.
"Many vehicles will now be travelling twice the distance and going twice as long before undergoing the minimum safety check,'' MTA spokesman Ian Stronach said.
"Many drivers rely on this as their primary safety and operational assurance. In an automotive environment like ours, that is too long and too far.''
Mr Stronach said it was a "piecemeal deconstruction'' of the vehicle inspection regime that has served and protected motorists well for many years.
Road safety campaigner Clive Matthew-Wilson said the changes would result in more road deaths.
"Despite what people have been conned into believing, the current six-monthly WOF check is a major lifesaver.''
He dismissed Government claims that few accidents are caused by vehicle defects and that the six-monthly WOF are therefore an unnecessary expense.
"Take a typical situation where a child runs out in front of your car. Whether or not that child gets killed may well depend on the state of your vehicle's brakes and shock absorbers,'' he said.
The Government had done a brilliant job of presenting the changes as a measure to save ordinary motorists time and money, when actually the average motorist would save very little and may lose a lot, he said.
The NZ Transport Agency and the Ministry of Transport will tomorrow outline how they plan to implement the changes.
