What is bowtie analysis and how is it used in process safety?

Bowtie analysis is a risk visualization method combining fault tree (causes) and event tree (consequences) around a central hazardous event (top event). Left side shows threats and preventive barriers that could lead to the event; right side shows consequences and mitigating barriers if the event occurs. Barriers (controls) are shown as vertical lines blocking the pathway. Benefits: visual communication of risk, clear identification of barrier effectiveness, basis for barrier management, and connects to safety critical equipment list. Used in conjunction with HAZOP and LOPA to identify safety functions and assign responsibilities for barrier maintenance. Software tools enable dynamic bowtie with real-time barrier status.