WorkSafe says the PCBU (Person Conducting a Business or Undertaking) failed to comply with its duty, which exposed an individual to the risk of death or serious injury or serious illness.
M E Jukes & Son pleaded not guilty to a charge under sections 36(1)(a), 48(1) and (2) (C) of the Health and Safety at Work Act 2015.
Counsel Tim MacKenzie, appearing for WorkSafe, submitted that it was reasonably practicable for the company to have ensured its construction waste shredder was adequately guarded by a perimeter guard with interlocked access.
Interlocked access means the machine would automatically shut down when the access point was opened.
Edwin Boshier and Daniel Robinson, of Auckland law firm Duncan Cotterill, appearing for M E Jukes & Son, submitted that administrative controls, such as company rules and safety training, and existing safety measures were sufficient to protect workers from the risk of death or serious injury in foreseeable circumstances.
The offence of failing to comply with a duty that exposes an individual or individuals to risk of death or serious injury or serious illness carries a maximum fine of $1.5 million.
The court heard that workers would occasionally need to enter a part of the machine around the shredder to clear jammed material that could not be cleared from the observation area, and that employees were trained to make sure the machine was turned off before doing this.
Expert witnesses for the prosecution and defence spoke at length on the technical rules and best practice guidelines involved under New Zealand and Australian safety standards.
Expert evidence for the defence focused on the administrative controls being sufficient, while the court also heard from mechanical engineers for the prosecution about the need for physical guards, such as gates and fencing.
WorkSafe inspector Russell Young and his assistant inspector at the time of the incident, Scott Quate, were present in the courtroom and were witnesses.
Judge Cathcart formally adjourned the matter until a further hearing on August 8, when he will consider further submissions. His decision would then be reserved, he said.