Call-sign announcing?

With a GMRS license how often is one required to announce their FCC call-sign? Someone once told me every 15 minutes or so if you are having a long conversation. Is this true? Or more often? s there a place to find “the rules”…?

Found here: FCC Rules for the General Mobile Radio Service

[i]95.119 Station identification.

(a) Except as provided in paragraph (e), every GMRS station must transmit a station identification:

(1) Following the transmission of communications or a series of communications; and

(2) Every 15 minutes during a long transmission.

(b) The station identification is the call sign assigned to the GMRS station or system.

© A unit number may be included after the call sign in the identification.

(d) The station identification must be transmitted in:

(1) Voice in the English language; or

(2) International Morse code telegraphy.

(e) A station need not identify its transmissions if it automatically retransmits communications from another station which are properly identified. [/i]