This paper presents descriptive accounts from an ethnographic study of time-critical work in the domain of emergency response and the operative work of fire crews. The verbal communication as part of such work creates difficulties in providing accountability of the fire crew’s actions. The concept of work rhythms and temporal structures is used as an analytical framework. Design implications are presented suggesting that verbal communication should be made persistent, visible and accessible in order to support accountability. These design implications are discussed in relation to the fire crew’s work practice.