The absence of a gas detector on the first fire truck at the scene of a fatal Tamahere coolstore explosion and fire in April has been highlighted in a report into the incident.
One firefighter died and seven were badly injured when the Icepak coolstore exploded as firefighters were responding to a callout.
Results of an inquiry by the Fire Service were issued on Tuesday.
The 155-page report suggests the explosion occured after propane gas was ignited by unprotected electrical switchgear in the plant, which may have been affected by power cuts in the area that day.
It says a multi-gas detector from the first appliance was away for servicing.
But if a stenching agent, normally used with propane, had been used in the plant, the firefighters would have smelt the gas.
The report also says the Fire Service was not notified of hazardous substances at the plant and hazardous substances regulations were not complied with fully.
The report says the fundamental cause of the incident may lie in part in systemic defects in the regulatory environment and communication between various agencies.
Firefighters first at the scene have been commended for the way they handled the situation, while all struggling with injury.
National Fire Commander Mike Hall says the regulations relating to chemicals are highly complex and difficult, and agencies with jurisdiction in the area need to work together to fix the problem.
He says there is relief among the surviving officers that they were not responsible for the explosion.