Introduction

• The techniques of Hazop and Hazan were developed to identify and assess hazards in the process industries. Their use leads to safer plants, the elimination of many operational problems at the design stage, and improvements in reliability. They will only be effective, however, if there is a commitment to safety at all levels in an organization.
• HAZAN, similar to the risk reduction analyses it consists of three steps:

1. Estimate how often the incident will occur.
2. Estimate the consequence to.
3. Employees.
4. The public and the environment.
5. Plant and profit.
6. Compare the results of the above frequency and consequence with a target or criterion normally based on the principles of ‘As Low As Reasonably Possible’ (ALARP).