Hazard Study 0 and Hazard Study 1

Hazard Study 0

In short, Hazard Study 0 asks the question : ”Can the process be made inherently safer by changing for less hazardous materials or processes?” The aim of inherently safer design (ISD) is to make sure that even if things do go wrong, the process is still safe. An example of ISD is to make a vessel strong enough to withstand the highest pressure it could ever encounter, rather than protecting it in other ways such as by installing pressure relief.

Hazard Study 0 considers these inherent safety issues to see if safety can be improved at this early stage in design by, for example, using less toxic reactants, less flammable solvents, or equipment that is “safe by design”.

Hazard Study 1

HS1 is best carried out when the basic process flow is known. (All that is needed is a block diagram showing the different processing steps. A full PFDProbability of Failure on Demand is not required.) HS1 aims to identify the major hazards present, the main control measures required and the main health, safety and environmental legislation applicable to the project.

The cost of a change

As can be seen from the diagram above, the early-stage hazard studies (HS0/1/2) make good economic sense as well as good safety sense, because it is still relatively cheap to make changes at this stage, compared with later in the design.

What =Method can do for you

• Provide experienced study facilitators for HS0 and HS1.
• Train and give mentoring support to aspiring hazard study leaders.
• Provide training for HazOp team members.