We are publishing a series of posts to do with system availability and reliability. The first post in the series is Improving System Availability ― Part 1: Reliability, Maintainability, and Availability. It starts as follows.

Many organizations have mature safety programs, yet they continue to experience avoidable production losses, escalating maintenance costs, and declining asset performance. These outcomes are often addressed using the language and tools of safety risk management, even though the underlying problems are fundamentally different.

Formal risk management programs typically pursue two broad objectives. The first is to improve safety, protect the environment, and maintain a license to operate. The second objective is to enhance profitability by reducing downtime and improving asset utilization. Because both objectives are framed in terms of ‘risk reduction’, safety and reliability are frequently treated as variations of the same problem. It is therefore commonly assumed that improvements in safety will automatically improve reliability, and that reliability initiatives will inherently improve safety.

This assumption is misleading, and even counterproductive.

Safety and reliability belong to different classes of decision problems, governed by different constraints and measures of success. Understanding this distinction is essential if risk management is to be used effectively to improve system performance.