In a letter to the editor of The Press, published on Monday, Christchurch firefighter Darren Aitken accuses the service of restricting its workers.
Mr Aitken says that 24 hours after the quake, fire staff in the CBD were barely able to help because managers had limited their actions, and as well, several managers went home immediately after the quake.
He says Fire Service management needs to be gutted from top to bottom and replaced by people who understand firefighters are skilled at what they do.
The service's national commander, Paul Baxter, denies the claims saying managers swung into action straight away and those who were further afield arrived as soon as they could.
Mr Baxter says a number of crews were redirected to the eastern suburbs a few days after the quake, but that was only when there was a stronger need for assistance in those communities.
Mr Baxter is not confirming whether Mr Aitken is under investigation for serious misconduct.
Internal Affairs Minister Amy Adams says she has no intention of getting involved in the dispute, unless she has to.
She says it is an employment matter for the Fire Service to handle and she will stay away from the issue unless she is asked to step in.