A couple of weeks ago, I wrote about how the Process Safety Information (PSI) “Safe Upper and Lower Limits” will differ from those “Safe Upper and Lower Operating Limits” found in our Operating Procedures. The article needed to be written as it received over 10,000 hits, and the e-mails continued with positive comments and more questions. Several have asked for a real-life example of how this works and what it would look like when developing our PSI. One member gave me a perfect example to show how this can all go awry quickly and in a big way.
In this article, I will use his/her process example to attempt to demonstrate why OSHA and EPA placed this requirement as part of our PSI and WHY we are required to evaluate the consequences of deviations of our PROCESS DESIGN as part of our PSI development.
Here is OSHA/EPA’s requirement for Information pertaining to the technology of the process as it relates to safe upper and lower limits: