Emergency call taking is a high-stake situation where errorless decisions must be made swiftly—often under ambiguous, emotionally volatile and time-critical conditions. The use of the telephone restricts operators to a single modality—their hearing—hindering multiple sensory perception.  Through an in-situ study, using observations, interviews and archival records, we develop understanding of operators every day decision practices. Emergency operators emphasize the role of sociomaterial cues, such as background sounds and the emotional state of the caller, when making sense of emergency calls. More specifically, they engage in matching and mismatching of non-verbal cues, facets that constitute building blocks for contraction and broadening of the sensemaking frame. Theoretical and practical implications of such single modal sensemaking are further discussed.