Senior station officer is a rank in the New Zealand Fire Service. In career fire stations, an SSO will be the officer in charge of a single watch at a station with multiple appliances. They will ride as officer on one appliance, with the other appliances being commanded by station officers.
Senior station officer is also a rank in the MFB (Metropolitan Fire Brigade) in Melbourne, Australia. In the MFB a Senior Station Officer has a Silver helmet with Station Officers having Blue helmets. It also became a rank in the CFA (Country Fire Authority) in 2010.
In a volunteer brigade there will usually be only one SSO, and some volunteer brigades have no SSO positions at all. Here the SSO acts as the senior operational officer, to allow the chief fire officer and their deputy to focus on the running of the brigade.
In both career and volunteer situations, an SSO reports to a CFO.
In New Zealand, the senior station officer rank insignia is two impellers. SSOs wear red helmets with two blue stripes (prior to November 2013, they wore yellow helmets with two blue stripes).