Petty Officer Second Class

Petty Officer Second Class is a non-commissioned officer rate in Starfleet. Second Class Petty Officers have been promoted within their rating (occupational speciality) from Petty Officer Third Class. They may be addressed by their rating, such as "Hosptial Corpsman Second Class" or "Transporter Operator Second Class" as well as by the more generic Petty Officer Second Class. PO2s take a fleet-wide competitive exam to be promoted to Petty Officer First Class.