- Challis International



Through research conducted to established standards of academic rigour, Dr David Challis has identified a number of factors that can be used to help organisations evaluate  whether/not an eHAZOP is required for a given project.

These factors are :

  1. Safety
  2. Financial
  3. Compliance and Environment
  4. People
  5. (Technological) Complexity
  6. General/Culture

Key attributes and questions that underpin each factor have been identified and an eHAZOP diagnostic instrument has been developed.


154 projects where eHAZOP have been implemented were reviewed.

Projects where eHAZOP was not implemented have not been reviewed.

The results are provided on the graph that follows. There are three key observations :

  1. Evidence of a strong negative correlation between perceptions of eHAZOP value added and eHAZOP instrument factor scores providing strong support for the instrument. Note Higher eHAZOP Instrument scores reflect environments with lower project risks.
  2. eHAZOP instrument factor scores are biased towards the negative (ie more scores on the LHS of the 50% midpoint) reflecting the magnitude of the eHAZOP improvement opportunity available and providing strong support for the value of the instrument.
  3. The line of best fit progresses through the 20% eHAZOP value quintile indicating that even for those projects where project success factors were in place (eg. strong safety culture, experienced project team, established technologies used) eHAZOP yielded value to the project.



Score interpretation :

Green Zone

eHAZOP generally not required, but may be completed as a value adding task.


eHAZOP strongly advisable/generally required but peer review may be acceptable.


eHAZOP strongly recommended.



Challis International has developed a survey diagnostic tool that may be used by organisations to assist in assessing the requirement for an eHAZOP study. The diagnostic may be accessed by contacting Dr David Challis