Process Safety Management of Highly Hazardous Chemicals - Part 1

By Jerry Lacatena

Overview

A dreaded scenario for any company that works with highly hazardous substances is an incident that results in death, injury, and/or economic loss. Several catastrophes have occurred in recent years, such as the accidents in Bhopal, India (1984), Norco, LA (1988), Pasadena, TX (1989), and Texas City, TX (2005) to mention a few.

The US Chemical Safety Board’s (CSB) investigations of several recent US process industry incidents, many of which resulted in loss of life, addressed the following contributing factors:

So based on CSB’s findings, although companies have generally recognized the importance of addressing process safety considerations in their operations, there still appears to be considerable room for improvement.

Local governments, operating companies, and other technical experts have developed systematic approaches focused on reducing the probability of future events and protecting the workplace. In the US, the OSHA Standard 1910.119, Process Safety Management of Highly Hazardous Chemicals, is a regulation that gives employers a methodology intended to manage highly hazardous chemicals, and ultimately try to prevent catastrophic incidents and release of toxic, reactive, flammable, or explosive chemicals. While OSHA Standard 1910.119 only applies in the US, companies located elsewhere may also consider using its framework for guidance, and to complement local regulatory requirements, as appropriate.

This brief article highlights some of the basic elements of OSHA Standard 1910.119, who is covered by it, and some technical information that processing companies should be aware of that were largely obtained from the source documentation. The intent is to provide more information in later articles.

Process Safety Management

OSHA recognizes that each company and process may be unique, and there is a need to integrate technology, operating procedures, and standard management protocols. They want all applicable businesses to follow specific steps in order to identify factors in each process that have the potential for catastrophe, and to take action to eliminate or minimize the potential release of highly hazardous substances to achieve a safe working environment.

Process Safety Management (PSM) is a framework for identifying potential hazards and managing the serious risks associated with processes that involve highly hazardous chemicals. OSHA defines the standard's purpose as preventing or minimizing the consequences of catastrophic releases of toxic, reactive, flammable, or explosive chemicals that may result in toxic, fire, or explosion hazards. The regulation further defines a catastrophic release to mean a major uncontrolled emission, fire, or explosion, involving one or more highly hazardous chemicals, that presents serious danger to people in the workplace. OSHA expects companies to manage any activity in which they use, manufacture, handle, store, or transport a highly hazardous chemical.

OSHA's PSM regulation covers employers in a number of industries, with emphasis on manufacturing, particularly chemicals, transportation equipment, and fabricated metal products. The size of the company is irrelevant; what counts is the quantity of hazardous materials being used or stored. Thus, a “small” company with limited internal technical resources must still comply with the regulation.

Requirements contained in the PSM standard generally fall into the following main categories:

Companies can also meet certain PSM requirements as a result of their compliance with other regulations.

Elements of the PSM Standard

The standard covers the following elements (refer to OSHA Standard 1910.119 for details):

What Facilities are Covered?

So far, OSHA listed 137 highly hazardous chemicals, toxics, and reactive substances in its Appendix A. This list gives the chemical name, Chemical Abstract Service (CAS) Number, and Threshold Quantity in Pounds (TQ) for each substance. Companies that have or use at least the specified quantity of the substance are covered by the regulation. Please refer to the OSHA standard for this list.

The regulation also applies to any process that involves a flammable liquid or gas on-site in one location, in a quantity of 10,000 pounds or more. OSHA interprets “on-site in one location” to mean an area under the company’s control. The regulation also applies to any group of vessels that are interconnected, or in separate vessels that are close enough in proximity that the highly hazardous chemical could be involved in a potential catastrophic release. The regulation also provides some exclusions (e.g., if your flammable liquids or gases are used only for fuel).

Additional information on this subject will follow in future brief articles.