Disciplinary stages start with an informal or verbal warning for a minor breach, followed by a written warning.
If a trader gets three written warnings over two years, the council will call a formal meeting.
Sanctions could be a suspension or termination of their market licence. But traders will have a right of appeal to the council’s chief executive.
Mr Dent said the changes were needed as “currently, if we issue a verbal warning, we have no process to follow”.
He added: “We know that and the traders know that. But if we get a proper system, it will support us all and the market supervisor.”
Conservative councillor Rosemary Elms said: “I welcome this code of conduct too.
“It’s long overdue, to be honest. I fully support this.”