Shell process safety initiatives target sweet spot for reducing risk
By Katie Mazerov, contributing editor
“No job is so important it can’t be done safely” was the message delivered by Dr Arthur Woltman at the IADC Advanced Rig Technology Conference & Exhibition, 20 September in Houston. Dr Woltman, principal engineer for Shell Global, presented an overview of his company’s Manufacturing/Production Operations’ Safety Critical Instrumentation, a key component of a multi-tiered approach to process safety throughout the company.
“Shell has a very rigorous and systematic approach to managing health, safety and environmental procedures, and strives to create a safe and secure workplace,” Dr Woltman said. “Our safety critical instrumentation sophistication has marched in lock-step with technology advances in automation, control and optimization.”
The company places a high priority on process safety, the practice of reducing the risk for catastrophic events that lead to fires, explosions and releases of product into the environment, he explained. “This is best achieved by inherently safe design and construction to reduce risk by passive measures over the long term,” he said. “We want solutions that are fault-avoidant, fault-tolerant and fail-safe.”
Such systems will become increasingly important as hydrocarbon recovery becomes more complex, with increasing demands on technology and automation, particularly in the deepwater arena, he said.
To that end, Shell has launched initiatives that set high standards for staff, design practices, and the use of technologies (mechanical, pneumatic/hydraulic, electoral and electronic), by deploying appropriate methodologies aimed at reducing risk to as low as reasonably practical (ALARP).
From a personnel perspective, Shell puts an emphasis on training and identifying and improving competencies in various areas. “You gain ever-increasing competency through learning, testing, apprenticeships and successful demonstration of competencies in real projects,” Dr Woltman said. Alongside that effort, the company has created centers of excellence where older, experienced employees provide knowledge and recommendations to junior engineers through a practice he called “leveraged knowledge.”
“We have a network of experts ranging from top scientists and engineers to subject matter experts who have demonstrated superior knowledge throughout the years in their respective areas,” Dr Woltman noted. “Those experts play a huge role in helping the company’s ongoing goal of implementing standards that comply with or exceed industry design and engineering practices.”
Shell uses a Hazards and Effects Management Process methodology to identify hazards and put safeguards in place to prevent events from occurring. Under that umbrella, several methodologies are applied for measuring and responding to various levels of risk and appropriate barriers to those risks. One tool, a system called LOPA (Layer of Protection Analysis), is used to determine frequencies of potential catastrophic events. The tool identifies the various layers of protection in place to reduce risk.
A “bowtie” risk model provides a method of measuring threats, safeguards and consequences. On one side of the model are the threats with barriers that reduce the likelihood of a catastrophe. The other side, response and recovery, includes ways of mitigating consequences.
A SIFpro tool incorporates the various methodologies and identifies how safety instrumentation function should be determined, how powerful it should be and how it should be designed. Built into the SIFpro tool are barriers and threats, frequencies and consequences. Although SIFpro has not been applied to Shell’s drilling operations, Dr Woltman said he saw no reason that it couldn’t be applied there.
Risks also are targeted as intolerable to tolerable. “We have targets we shoot for that we consider risk to be low,” Dr Woltman explained. “We can’t reduce the risk to zero, but we can try to reduce risk such that it is a fraction of what it would be otherwise. We attempt to drive the risk potential as low as we can, until it is no longer reasonable or economically feasible because the time, difficulty and cost of further reduction measures would be disproportionate to any additional risk reduction obtained.” The sweet spot is identified by using the LOPA and ALARP methodologies.
In developing better process safety performance, it is important to recognize that it is an ongoing process, Dr Woltman noted. “Unfortunately, as we achieve ever better process safety performance, our successes can erode evidence of the need for best-in-class process safety tools and methodology. We need to avoid complacency.”
SIFpro is a trademark of Shell.