Handling changes to process applications is never particularly easy, but when safety gets involved, it's a whole other ball game. Properly managing all the needs, variables and requirements inherent in altering any process safety system takes a calm, logical and almost obsessively methodical and well-documented approach. This is needed to overcome the uncertainties and potential dangers that can arise when high-stakes applications are maintained, repaired, updated or replaced.
"Hazards involve equipment failures, human errors, unforeseen chemical reactions or any situation that increases operating risk, such as potential deficiencies in safety management systems. Hazards can be introduced when change occurs, when modifications to a facility's operation are made, or when replacement equipment doesn't meet the design criteria of equipment being replaced," said Ulric Roy, Invensys Operations Management's lead engineer for Triconex safety systems, at a presentation this week at the Invensys North America Client Conference in Houston. "Other changes occur when operating procedures are modified, site staffing changes, or a company reorganizes. Changes that aren't carefully controlled increase operating risk and can directly cause or lead to catastrophic events."
To help eliminate or mitigate these risks, make sure new hazards aren't introduced and ensure that human and environmental safety aren't compromised, Roy said. "Consistent and effective management of change (MOC) is the most important element of the process safety management (PSM) program. It's the most difficult activity to implement, and it requires solid dedication from highly experienced resources and rigorous management commitment."
Roy added that maturation of MOC programs in industry has been very slow, but today there is more support that inspires confidence. "For the past 20 years, most of the initial chemical industry MOC implementation activity has been driven by regulatory influence," said Roy. "Since 1989, a lot of industry experience and guidelines have been developed, and computer technology has helped garner acceptance of new tools, like the risk-based process safety (RBPS) system approach. However, the crucial element is reliable performance. Your MOC process should be flexible and aim for ways to continuously improve."
Roy explained that a MOC process is an organized, systematic effort that includes administrative procedures for the review and approval of changes before they are implemented. "Your PSM program shall define the MOC elements in detail. You define where the MOC process applies—the physical areas of the facilities, such as fence-to-fence, the phases of the process life cycle and the source of changes, such as hardware, software, procedures, personnel or organization," he said. "A MOC process should be designed to fit your organizational structure, culture and workforce, and it should be revised periodically to ensure adaptability."
However, Roy cautioned that a MOC process that is circumvented or used in a parallel environment with no widespread acceptance and commitment is worse than having no MOC process. "An effective MOC process demands a significant commitment from line management, departmental support organizations and employees," said Roy. "Success begins at the top, when management demonstrates leadership and commitment by making sometimes-hard decisions in favor of safety."
To manage risk by eliminating it, Roy described MOC's main goals as:
- Eliminate MOC deficiencies in safety management systems.
- Reduce quantity and magnitude of risks.
- Expand MOC into each phase of the process life cycle.
- Expand MOC into non-traditional changes.
- Make the MOC process more fault-tolerant and resilient to circumvention or human error.
- Reduce the number of PSM audit findings.
- Monitor MOC performance on-site and from a central location, where resources are specialized and cost-effective.
- Achieve better MOC results with fewer resources, if possible.
To accomplish these goals, Roy added that users must manage a variety of types of changes in their process applications. These types include changes to process equipment, process controls, safety systems, site infrastructure, operations and technology, preventive inspection maintenance, procedures and staffing. Likewise, they also must use MOC in each life-cycle phase of their equipment, application or facility. These phases include R&D, conceptual, design, detailed engineering design, procurement and construction, start-up (atypical operation), normal operation (typical operation), maintenance and turnaround, extended shutdown (atypical operation) and decommissioning.
"MOC is not a form. It's a process," said Roy. The seven steps in the MOC process include:
- An employee originates a request for change (RFC).
- PSM personnel independent of the RFC originator review the request to identify potential risks (adverse impacts) and list the process safety information (PSI) elements that may need modification.
- Based on this review, a facility manager approves or rejects the change.
- If the change is approved, it's implemented.
- The PSI is modified to reflect the change.
- Before start-up of the change, affected personnel are informed and trained if necessary.
- These activities must be completed prior to pre-start-up safety review (PSSR).
"The MOC process is the gatekeeper—a trackable sign-on/sign-off sheet—of most other documents," added Roy. "But you define where the MOC process applies in your PSM program, as well as the phases of the process life cycle, and the source of changes, such as from hardware, software, procedures, personnel or organization.”