Petty officer , second class Petty officer , second class is the fifth enlisted rate in the U . S . Navy , U . S . Coast Guard , and the United States Naval Sea Cadet Corps , just above petty officer third class and below petty officer first class , and is a non - commissioned officer . It is equivalent to the rate of sergeant in the Army , Marine Corps and Staff Sergeant in the Air Force . Overview . Similar to petty officer third class , advancement to petty officer second class is dependent on time in service , performance evaluations by superiors , and rate ( technical specialty ) examinations . The advancement cycle is currently every 6 months . Only a certain number of billet s ( job openings for this rate ) open up biannually and all petty officers third class compete . The top scorers are chosen for advancement , but only in sufficient quantities to fill the billet s available . Job description . Petty officers serve a dual role as both technical experts and as leaders . Unlike the sailors below them , there is no such thing as an " undesignated petty officer . " Every petty officer has both a rate ( rank ) and rating ( job , similar to an MOS in other branches ) . A petty officer ' s full title is a combination of the two . Thus , a petty officer second class , who has the rating of interior communications electrician would properly be called an interior communications electrician second class . The term petty officer is , then , only used in abstract , the general sense , when referring to a group of petty officers of different ratings , or when the petty officer ' s rating is unknown . Often , the petty officer is just referred to by the shorthand designation , without using the surname . Thus EM2 Reyes would just be called EM2 . A petty officer second class may be generically referred to as PO2 when the sailor ' s rating is not known , although some prefer to be called simply " Petty Officer ( Martinez ) . " To address a petty officer , one would say , " Petty Officer Smith " , " Smith " , or " Sailor " ( the latter two forms being acceptable for use by those equal or greater in rate than the Petty Officer ) . It is uncommon to address a petty officer as simply , " Petty Officer " the way one might address an NCO in the Marine Corps as " Sergeant " . Also acceptable , but archaic , would be to address a petty officer or chief petty officer of any grade as " Mister Smith " or " Ms . Smith " . The use of " Ms . " or " Mister " is commonly only in reference to junior commissioned officers or warrant officers . Short form naming . Each rating has an official abbreviation , such as GM for gunner ' s mate , BU for builder , or BM for boatswain ' s mate . When combined with the petty officer level , this gives the shorthand for the petty officer ' s rate , such as IT2 for " information systems technician second class " . It is common practice to refer to the petty officer by this shorthand in all but the most formal correspondence ( such as printing and inscription on awards ) Promotion system . The Navy uses promotion points that they call " final multiple score " system , which considers the whole person by calculating a candidate ' s performance , experience , and knowledge into the individual ' s final multiple score . To advance a candidate must meet the time in rate eligibility , pass the advancement test , and have a final multiple higher than the minimum required to advance . Among enlisted sailors , 12 consecutive years of good conduct ( categorized as no court - martial convictions and no non - judicial punishment s ) entitles the sailor to wear a good conduct variation of their rate insignia : the chevrons which are normally red are replaced with gold . The perched eagle remains silver . However , the high year tenure initiative mandates that a petty officer second class may only have 14 years of service . If a PO2 fails to make petty officer first class within that time , the petty officer is involuntarily separated for not meeting advancement requirements . However , this may be waived in the event the sailor holds a critical rate , Navy Enlisted Classification or security clearance . Uniform . All U . S . Coast Guard petty officers wear red chevrons and red service stripes , until the rate of chief petty officer , where both chevrons and service stripes are gold .