Each start (end) event in a model of the EPC type is transformed into a start (end) event in a BPMN diagram. A process interface can precede or succeed the start (end) event in the EPC.
A start event has no incoming connection, and an end event has no outgoing connection in the control flow.
Other patterns
The process interface or the event must stand at the beginning of the control flow and may not have incoming connections.
The process interface or the event must stand at the end of the control flow and may not have outgoing connections.