What is Process Safety Management?

A Guide to OSHA’s Process Safety Management (PSM) Standard

Learn what is process safety management, why it’s important, and how to implement a PSM program with all of the 14 elements

Published 28 Mar 2023

What is Process Safety Management?

Process safety management is a regulatory standard issued by the Occupational Safety and Health Administration (OSHA) for processes that use Highly Hazardous Chemicals (HHCs). The OSHA process safety management standard contains requirements for preventing catastrophic releases of toxic, reactive, flammable, or explosive chemicals.

While the full list of HHCs can be found in Appendix A of the OSHA PSM standard, it might also be helpful for chemical safety managers to know the basic definitions of toxic, reactive, flammable, and explosive. These are properties or characteristics of HHCs. 

According to the Center for Chemical Process Safety (CCPS):

• Toxic Material – an airborne agent that could result in acute adverse human health effects
• Reactive Material – a substance which enters into a chemical reaction with other stable or unstable material
• Flammable – a gas that can burn with a flame if mixed with a gaseous oxidizer such as air and then ignited
• Explosive – a chemical that causes a sudden release of pressure, gas, and heat when subjected to sudden shock, pressure, or high temperature

Why Is Process Safety Management Important?

One of the reasons why OSHA decided to create PSM is the Phillips disaster of 1989. In October of that year, an explosion and fire at the Phillips 66 Company’s Houston Chemical Complex (HCC) took the lives of 23 workers and injured 132 others. The event also resulted in $750,000,000 worth of property damage and a $4,000,000 fine issued by OSHA. 

However, even after OSHA had released the PSM standard in 1992, another disaster occurred at the BP Texas City refinery in 2005, leading to the deaths of 15 workers and 180 others injured. The company had to pay $2,000,000,000 to the victims of the disaster and their relatives as compensation. Repairs and lost profits also cost BP over $1,000,000,000. 

What Falls Under the PSM Standard and What Doesn’t

OSHA states that the process safety management standard applies to any process that involves a chemical with quantities at or above the specified threshold listed in Appendix A and any process that involves a Category 1 flammable gas or a flammable liquid with a flashpoint below 100 °F (37.8 °C) and in a quantity of 10,000 pounds (4535.9 kg) or more. 

Compliance with PSM is not required when hydrocarbon fuels are used solely for workplace consumption and when flammable liquids are kept below their normal boiling point. PSM also does not apply to retail facilities, oil or gas well drilling or servicing operations, and normally unoccupied remote facilities.

The 14 PSM Elements

For organizations with processes that involve the use of HHCs, complying with process safety management is crucial, not only because it’s a legal requirement, but also because the consequences of non-compliance are devastating. 

To prevent disasters such as the Phillips 1989 and the BP Texas City Refinery explosions, chemical safety managers need to ensure that each site has a process safety management program with all of the 14 elements.

 

1. Process Safety Information

Collect and document process safety information (PSI) on three aspects of the process: hazards, technology, and equipment. 

Information on the hazards of the HHCs must include toxicity information, permissible exposure limits, physical data, reactivity data, corrosivity data, thermal and chemical stability data, and hazardous effects of inadvertent mixing of different materials. If the site uses safety data sheets that meet the requirements of OSHA’s hazard communication standard, then the hazards part of the PSM element can be considered fulfilled.

For information related to the technology of the process, chemical safety managers need to include a block flow diagram or simplified process flow diagram, process chemistry, maximum intended inventory, safe upper and lower limits for temperatures, pressures, flows or compositions, and an evaluation of the consequences of deviation.

Some components to include in the information on equipment are materials of construction, piping and instrument diagrams, electrical classification, relief system design and design basis, ventilation system design, design codes and standards employed, material and energy balances, and safety systems such as interlocks, detection, or suppression systems.

2. Operating Procedures

Develop and implement operating procedures on how to safely proceed with the activities and tasks involved in the process. Operating procedures should be aligned with PSI and address the steps for each operating phase, operating limits, safety and health considerations, and safety systems and their functions.

Aside from PSI on hazards, other safety and health considerations are the precautions necessary to prevent exposure, control measures in case of exposure, quality control for raw materials, and control of hazardous chemical inventory levels.

3. Process Hazard Analysis

A process hazard analysis (PHA) is an evaluation of the hazards in the process. It should address any previous PSM incidents, engineering and administrative controls, and consequences of control failure. 

Only a special team can perform a PHA. The special team should consist of those with expertise in engineering and process operations, one who has experience in and knowledge of the specific process, and another who is familiar with the specific PHA methodology to be used.

Examples of PHA methodologies are what-if scenarios, checklist, combination of what-if scenarios and checklist, hazard and operability study (HAZOP), failure mode and effects analysis (FMEA), and fault tree analysis. 

Given that the key provision of process safety management is the process hazard analysis element, PHAs should be updated and revalidated at least every 5 years after the initial PHA.

4. Employee Participation

Before proceeding with the other elements, chemical safety managers will need to develop a plan of action on implementing employee participation in the PSM program. Additionally, chemical safety managers must consult with employees on how to proceed with each element as well as provide access to information relevant to the program.

5. Training

Aside from participating in the PSM program, employees should receive adequate training on the process, operating procedures, emergency operations, specific safety and health hazards, and safe work practices. Chemical safety managers should also conduct refresher training at least every 3 years, or more often if necessary. 

All training must be documented and include the identity of the employee, the date of training, and verification that the employee understands the subject matter of the training.

6. Contractors

This PSM element applies to contractors performing maintenance or repair, turnaround, major renovation, and specialty work. Chemical safety managers should review the contractor’s safety performance and programs before selecting them. 

After selection, chemical safety managers must periodically evaluate the performance of the chosen contractor. They should also consider giving the contractor’s employees a site induction to brief them on the potential hazards related to the work, process, or site.

7. Mechanical Integrity

Maintain the mechanical integrity of process equipment such as pressure vessels, storage tanks, piping systems, pumps, relief and vent systems, monitoring devices, sensors, alarms, and interlocks. Record inspections and tests performed on process equipment. If there are deficiencies outside acceptable limits, chemical safety managers should correct them before further use.

Make sure to use tracking tools, software, or devices that would ease the monitoring of these mechanical equipment. This helps keep an eye on the status of your process equipment and modify any deficiencies before they lead to an accident.

8. Incident Investigation

A PSM incident is any incident which resulted in or could have reasonably resulted in a catastrophic release of a HHC. 

Whenever a PSM incident occurs, chemical safety managers must initiate an investigation not later than 48 hours after the incident. At the end of the investigation, the primary cause and the factors that contributed to the incident should be identified in the report. The investigation report should also contain recommendations resulting from the investigation. 

Once the report has been filed, chemical safety managers must address and resolve the report findings as soon as possible. Any measures or corrective actions from the report’s recommendations should also be promptly implemented.

When the investigation report has been resolved, all those affected by the PSM incident (or could have been, in the scenario that the incident was controlled before the catastrophic release) should thoroughly review the report and decide if further investigation is needed.

9. Management of Change

Before making any changes to chemicals, technology, equipment, or facilities, prepare a management of change (MOC) procedure. It should address the technical basis for the proposed change, its impact on safety and health, modifications to operating procedures, and the authorization requirements and time period needed for the proposed change.

10. Pre-Startup Safety Review

For new and modified facilities, chemical safety managers must perform a pre-startup safety review. The PSSR should confirm that construction and equipment are in accordance with design specifications, operating procedures have been established, and all employee training is complete. Additionally, there must be a MOC procedure for modified facilities and a PHA has to be performed for new facilities.

11. Emergency Planning and Response

Develop an emergency action plan (EAP) for the entire site. It should meet the requirements of the EAP OSHA standard and include procedures for handling small releases of HHCs. If the site is under the Hazardous Waste Operations and Emergency Response (HAZWOPER) OSHA standard, ensure that the EAP meets the requirements of that standard as well.

12. Hot Work Permit

A hot work permit is issued whenever hot work operations are conducted on or near a process. Before requesting or issuing a hot work permit, chemical safety managers must ensure that
the fire prevention and protection requirements of the Welding, Cutting, and Brazing OSHA standard have been implemented. The hot work permit will verify this and also specify the date/s authorized for hot work and the object/s on which hot work is to be performed. 

13. Compliance Audits

Chemical safety managers must conduct compliance audits at least every 3 years to check if the site’s PSM program adheres to all of the elements. They will also need to determine and document an appropriate response to each of the findings in the compliance audit reports. Organizations are required by the PSM standard to keep the two most recent compliance audit reports.

14. Trade Secrets

Without regard to possible trade secret status, all information necessary to comply with the PSM standard should be made available to those involved in the PSM program. However, organizations are allowed to require such persons to enter into confidentiality agreements not to disclose any trade secret information.