Wayne Boss suffered the injury at the New Year's Eve celebrations in Dunedin's Octagon last year.
WorkSafe New Zealand confirmed in a statement to the Otago Daily Times that the investigation was at an end.
"WorkSafe’s investigation has concluded and no charges will be laid over this incident.
"The victim has been informed," a WorkSafe spokesperson said.
Boss told the Otago Daily Times today he was disappointed by the decision, but hoped there would at least be tougher regulations placed on public firework displays as a result of the incident.
"I don't think there would be any member of the public that wouldn't think the same as me - that you should be able to attend an organised public event or professional display in the correct area and not come out safely.
"But that didn't happen.''
Boss was informed of WorkSafe's decision two weeks ago.
He remains on leave from his job as a senior environmental health officer at the council and was still adjusting to life with restricted vision.
The council's independent investigation into the incident was completed earlier this year.
It found there was not enough evidence to clearly show whether the firework responsible was from the council's display or whether it was let off by a member of the public.
VIDEO: Wayne Boss talks to the ODT earlier this year about his injuries
Exclusion zone extended
Dunedin City Council events manager Joy Gunn said today that a public exclusion zone would be extended for this year's New Year's Eve fireworks display in The Octagon.
No personal fireworks would be permitted for safety reasons, and there would be more security guards at the event, Gunn said.
The public exclusion zone would be extended into areas such as Harrop St and they would be closed for 15 minutes before and 15 minutes after the display.
