Police officers who shot dead a man following a siege in Brisbane acted professionally and in accordance with official procedures, a coroner has found.

READ MORE: Kiwi father shot dead by police in Brisbane

Three special emergency response team officers opened fire on 42-year-old New Zealand man Shaun Kumeroa at an Inala carport in September 2014 when Mr Kumeroa aimed a replica pistol at them following a near four-hour siege.

Delivering findings from the inquest into Mr Kumeroa's death, Queensland Coroner Terry Ryan accepted officers couldn't have known the gun was a fake and had no other option than to treat it as a fully functioning firearm.