Contentious health and safety changes have passed - and school principals remain worried they could face "draconian" punishment if things go wrong.
Workplace Relations and Safety Minister Michael Woodhouse has said such fears are unfounded.
The Health and Safety Reform Bill passed its third and final reading in Parliament last night.
It was drafted to implement recommendations of the royal commission on the Pike River coal mine disaster, in which 29 men died, and of the Independent Taskforce on Workplace Health and Safety.
It was watered down after objections in the National caucus, and businesses with fewer than 20 workers will not now need health and safety representatives.
But businesses deemed high risk will have to have safety representatives, regardless of size. The Government has been mocked for giving high-risk status to worm farming, lavender growing and mini-golf, but not dairy and cattle farming.
All categories are to be confirmed.
The principal of Rotorua's John Paul College, Patrick Walsh, who is also spokesman for the Secondary Principals' Association, said school leaders were questioning why they faced heavy penalties, when the legislation could have targeted industries such as mining, forestry and farming.
"The ironic twist in it for us is that farming has ended up with substantial concessions and exemptions."
Principals were concerned they were identified as officers under the law and could face fines of up to $600,000 or up to five years in jail.
Mr Woodhouse has said schools that are complying now under the existing health and safety law have nothing to fear.
Principals were already liable for sizeable penalties under the former regulations, but Mr Walsh questioned why those should be increased by any amount.
He accepted that the risk of prosecution was small if a school had good policies and practices.
"But we think the fines and terms of imprisonment are draconian and inappropriate in the education sector - you are talking up to $600,000, and you can't insure against a fine."
While boards of trustees could be held liable for accidents, individual members could not be.
That made sense as they were volunteers, Mr Walsh said, but it set up a tension with principals, who were individually liable.
Such a chilling effect could curtail activities such as school camps, he said, and would also make recruiting principals more difficult.
"You can see that a board might be more gung ho in approving camps ... .whereas a principal, because they are personally liable, would be more risk-averse."
Mr Woodhouse said the reforms were a major step in addressing workplace deaths and injuries.