But, the regulator has begun criminal proceedings in the NSW District Court against Richard Wayne Simmons, whose truck company RW & LM Simmons employed Mr Norman.

The regulator will allege Mr Simmons failed a duty to ensure Mr Norman’s health and safety.

Mr Norman, 53, died in hospital after the tailgate of a truck he was cleaning swung down and crushed his head against the body of the trailer.

A report last month by the regulator said Mr Norman and two workmates were cleaning the truck with shovels because Mr Norman believed they had been stopped from using the wash bay because of problems with coal clogging the drains.

But, in saying on Wednesday why it was accepting Bloomfield’s offer of a work health and safety undertaking, the regulator said it could find no evidence Bloomfield had “issued a directive” that the wash bay could not be used by the contract company, and that other workers continued to use it.

It found no “direct evidence to establish that Bloomfield was aware the contractor had ceased using the wash bay”.

“Given the above evidence, it is arguable whether Bloomfield could have reasonably foreseen the specific risk posed by the change in practice by the contractor, which ultimately resulted in the death of Mr Norman,” the regulator said.

But, Bloomfield still had a general duty of care to Mr Norman under the Work Health and Safety Act that “could not be contracted or delegated out”.

The regulator said the undertaking offered by Bloomfield reflected the seriousness of its obligations.

The $500,000-plus cost, together with $85,000 in remedial actions since the accident, was in line with a $450,000 penalty recently imposed on Newcrest Mining after a court found its failings had directly contributed to the death of one of its workers.

It said the undertaking would provide “far greater benefits” to the workforce, the industry and the community than any other response, including criminal prosecution.

The undertaking’s major points include notices detailing the situation in the Newcastle Herald and Singleton Argus, $50,000 to Hunter Medical Research Institute for brain injury research, two safety videos costing an estimated $55,000 and a mental health resource kit costing an estimated $285,000.

Bloomfield issued a statement that noted there would be no prosecution against it, while RW & LM Simmons declined to comment when contacted.