A health and safety inspector for the Department of Labour says it is not possible to fully service all mines, tunnels and quarries in New Zealand because of a lack of staff.
Michael Firmin was giving evidence on Tuesday to the Royal Commission inquiring into the Pike River coal mine disaster, in which 29 men died last November.
He said he was currently the only mine inspector in New Zealand, with the recent resignation of the second inspector, who would be replaced.
He is responsible for about 1000 quarries around New Zealand, more than 20 mines in the South Island and more in the North Island.
Mr Firmin said his department had originally sought four inspectors and a chief inspector, but a sufficient budget was not available. He said the salary range for an inspector was about $50,000 to $76,000.
He said inspectors in the Department of Labour had to develop a risk assessment formula to justify visits to underground mines. The riskiest mines were to be visited four times a year.
He said he was challenged by the department's Mine Steering Group about three years ago on how many visits were needed. He said the group wasn't trying to stop him, but was asking him to justify the inspections.
Mr Firmin also said since his appointment as a coal mines inspector in 1999, he was unaware of any underground coal employee or health and safety representative calling the department about a safety issue.
'Snapshot view' - lawyer
Earlier on Tuesday, a lawyer for the Pike River mine families said it was a numbers game for the Department of Labour in having only two underground inspectors at the time of the mine explosions.
Nicholas Davidson, QC, said that because the Labour Department did not rate mining as among the top five industries for industrial accidents, it was not a priority.
Mr Davidson said a report to the department noted it was extraordinarily difficult for two inspectors to address issues of mining culture because they made only occasional visits to mines and had only a snapshot view of what was happening underground.
He questioned the department's workplace health and safety manager, James Murphy, who said there were finite resources available to the department and it was an ongoing issue, but a reality the department had to deal with.
The inquiry is sitting in Greymouth.