Each HAZOP deviation is analysed identifying the potential Causes, including:

  • Malfunction of process control systems;
  • Blockages;
  • Operational Error (e.g. opening wrong valve, failure to respond to signals, etc.);
  • Faulty maintenance activities;
  • Failure of utilities (power supply, control system, or other utilities).

Further guidelines in relation to causes are:

  • Equipment is assumed to be designed to appropriate earthquake, wind, and storm and other environmental requirements, therefore these are not treated as Causes
  • Manual valves marked as LO/LC/CSO/CSC will not be considered to change their position by operator error as a cause
Category: HAZOP