改进的变更管理

The advancing development of technology and digitalization in the gas analysis market offers significant benefits for end users, including reduced costs, less downtime, and greater efficiency.

However, the increased Industry 4.0 connectivity enabled by these improvements will create new challenges to security and consistency of operation that need to be expertly addressed.

When a component of a Safety Instrumented Function (SIF) has software-configurable elements related to the safety function, it’s important to ensure that the configuration is always correct.

For a gas analyzer, examples of these safety related software configurable elements include, the mA output Jam level to use under fault conditions, the measurement range assigned to the mA output, the measurement path length, and the routing configuration to apply a mA input providing pressure measurement into a gas measurement compensation function contributing to accurate measurement.

Field instrumentation has, traditionally, not focused on security. A small number of role-based access levels may afford some protection: for example, Viewer, Operator, and Supervisor access levels, each protected by a basic password/code.

While a Supervisor level login may somewhat limit changes to the configuration of a safety function, any individual who knows the Supervisor password has that access. Role-based access means there is no record of who, at an individual level, logged in – it was just someone acting as a Supervisor. Often there are no logs to track the time, date and detail of a configuration change.

Use of a Supervisor level of access can become commonplace because it unlocks everything and means passwords are seen not to ‘get in the way’. A side-effect of this can be the increased risk of an unintentional change to the safety configuration. This can, in turn, either allow dangerous conditions to go undiagnosed, or cause unintentional process shutdown, both of which result in unnecessary costs.

The use of minimal security is a historical hangover related to several factors: this type of equipment having little connectivity, industrial cybersecurity not traditionally being a significant concern, and the use of highly resource-constrained microcontrollers and memory components, which limited device capability.

However, times have changed. Connectivity has rapidly increased, bringing considerable benefits but also increased risk. Industrial cybersecurity has become a significant concern, with external threats, supply chain threats and, unfortunately, also industrial insider threats.  Resource constraints are largely a thing of the past with high-performance microcontrollers and high capacity memory readily available at low cost.

Instrumentation, including gas analysis equipment, must now carefully consider both security and safety. Without adequate security, safety cannot be adequately assured. Although, it is also worth noting that security controls can also hinder safety, so both must be considered jointly.

For now, in terms of change management, increased availability of Ethernet at the field device level, particularly with the advent of Advanced Physical Layer (APL) Ethernet, allows field instruments to more easily tap into existing Enterprise Identity-based access management systems.

Instrument access permissions could be assigned to individuals. Consistent identity-based access will better restrict access to instrumentation configuration and enable traceability at an individual level.

Human-machine interface (HMI) design aims to minimize operator error at high-stress moments. This could be improved to minimize inadvertent safety configuration changes by requiring a second re-authentication, in the same way that online banking requires re-authentication before transferring funds.

A further layer of protection could be added using dual-identity authentication, requiring any two sufficiently privileged individuals to log in, to confirm a change to safety-related configuration.

So, while digitalization does raise change management security concerns, it’s clear that these issues can be effectively addressed and could lead to more resilient, safer systems that offer greater performance benefits. A future blog will delve deeper into other aspects of security and trustworthiness of analytical instrumentation.