Recent Blog Posts

PSI Explained: Materials of Construction

May 2nd, 2017

The owner of a PSM chemical process must gather information which describes the materials used in the construction of the process equipment. Typically, this will not be developed from scratch, but rather will be the compilation of equipment manuals, data reports, bulletins, catalogs, cut sheets, and drawings. For a process which utilizes ASME pressure vessels […]

PSI Explained: Safe Upper and Lower Limits / Consequence of Deviation

April 18th, 2017

Title 8 CCR §5189(d)(2)(D)-(E) and Title 29 CFR §1910.119(d)(2)(i)(D)-(E) require that the information pertaining to the technology of the process include “Safe upper and lower limits for such items as temperatures, pressures, flows or compositions; and, an evaluation of the consequences of deviations, including those affecting the safety and health of employees.” It is worth […]

PSI Explained: Maximum Intended Inventory

April 4th, 2017

One often discussed requirements within PSI, is the documentation concerning Maximum Intended Inventory. The meaning of maximum intended inventory is exactly what the words imply – the maximum chemical inventory that a facility intends to utilize (have onsite) at any time. For a transient process in which a chemical is consumed, this often corresponds to […]

PSI Explained: Process Chemistry

March 20th, 2017

The information pertaining to the technology in the process must also include a description of any chemistry involved in the process. For processes which manufacture chemicals this is particularly important since the chemical reactions are the basis for the existence of the process. Process chemistry is trivial for processes in which a chemical is merely […]

PSI Explained: Block Flow and Process Flow Diagrams

March 7th, 2017

In order to adequately explain the technology of a chemical process a Block Flow Diagram (BFD) or simplified Process Flow Diagram (PFD) must be prepared. Ideally the BFD/PFD will fit on a single sheet of paper and clearly outline the “flow” of the chemical throughout the process. For a closed-loop process such as an ammonia […]