# The Operations Gradient: Improving Safety in Complex Systems

DevFeed: [The Operations Gradient: Improving Safety in Complex Systems](<https://devfeed.tech/articles/the-operations-gradient-improving-safety-in-complex-systems-12458.md>)

Original publisher: [Read original article](<http://brooker.co.za/blog/2014/06/29/rasmussen.html>)

Author: Marc Brooker

Published: 2014-06-29T00:00:00Z

Content type: opinion

Language: en

Sources: [Marc Brooker's Blog](<https://devfeed.tech/sources/marc-brooker-s-blog.md>), [Marc Brooker's Blog](<https://devfeed.tech/sources/marc-brooker-s-blog-2.md>)

Topics: [Complex Systems](<https://devfeed.tech/topics/complex-systems.md>), [systems](<https://devfeed.tech/topics/systems.md>), [Availability](<https://devfeed.tech/topics/availability.md>), [monitor](<https://devfeed.tech/topics/monitor.md>)

Tags: [availability](<https://devfeed.tech/tags/availability.md>), [complex-systems](<https://devfeed.tech/tags/complex-systems.md>), [cost](<https://devfeed.tech/tags/cost.md>), [engineering](<https://devfeed.tech/tags/engineering.md>), [management](<https://devfeed.tech/tags/management.md>), [monitor](<https://devfeed.tech/tags/monitor.md>), [operations](<https://devfeed.tech/tags/operations.md>), [safety](<https://devfeed.tech/tags/safety.md>), [systems](<https://devfeed.tech/tags/systems.md>)

## AI overview

The article discusses Richard Cook's lecture on Rasmussen's model of system safety. It explains how economic and engineering pressures can move complex systems toward safety boundaries, while defence-in-depth protections may gradually degrade. It recommends conscious attention to safety, availability, durability, error margins, perceived performance boundaries, and monitoring.

## Source excerpt

The Operations Gradient: Improving Safety in Complex Systems Can we improve the safety of complex systems by listening to operators more? This week, I watched an excellent lecture by Richard Cook. He goes in some detail about why failures happen, through the lens of Rasmussen's model of system safety. If you build or maintain any kind of complex system, don't miss this lecture. What is surprising is not that there are so many accidents, it's that there are so few. The model that takes up most of the lecture is best expressed in Rasmussen's Risk Management in a Dynamic Society: A Modelling Problem, a classic paper that deserves more attention among engineers. The core of the insight of the model from Rasmussen's paper comes from Figure 3: Rasmussen describes the process of developing systems as an adaptive search within a boundary defined by a set of economic constraints (it's not economically viable to run the system beyond this boundary), engineering effort constraints (there are not enough actors to push the system beyond this boundary), and safety constraints (the system has failed beyond this boundary). The traditional balance between engineering effort and economic return plays out in pushing the operating point of the system away from two of these boundaries. From the paper: During the adaptive search the actors have ample opportunity to identify an effort gradient and management will normally supply an effective cost gradient. The combination of optimizing for these two gradients tends to push the operating point towards the safety boundary (or boundary of acceptable performance). A conscious push for safety (or availability, durability and other safety-related properties) forces the operating point away from this boundary. One danger of this is that the position of the safety boundary is not always obvious, and it's also not a single clean line. From the paper: in systems designed according to a defence-in-depth strategy, the defenses are likely to degenerat