For enhanced interoperability of safety and non-safety communications, a synchronous interval is divided into a safety channel interval and an open interval instead of a CCH (control channel) interval and SCH (service channel) interval. For a single-radio device, a control interval, in place of an open interval should be scheduled at least once every maximum service scheduling period. Such a control interval is dedicated for CCH (and SCH) operation. For a multi-radio device, a control interval is scheduled at least once every maximum control interval on one of the radios support non-safety services (e.g. tolling).