The purpose of this exploratory study was to gain a better understanding of student L1 use in EFL classes by analyzing an audio-recording of Japanese learners. The study found thatthere were many instances of low-volume(volume of spoken output)L1use. Volume and code choice mark student exchanges as private, and Hancock (1997) labels such exchanges off-record. Not all L1 exchanges examined in the present study could be considered off-record as Japanese students expect to be able to use their L1 in class. However, when low-volume L1use did occur, it distinctly marked an exchange as off-record for the purpose of avoiding embarrassment. Natural breaks in the flow of the lesson also enabled students to clarify meaning in Japanese without recourse to low volumeL1 use. Recognizing off-record exchanges is important,teachers need to respect and appropriately deal with classroom discourse whichstudents do not intend for them to overhear.