Functional safety puts automated protection functions in place that ensures the safe operation of your facility. It covers all aspects of the equipment lifecycle. Specific focus should, therefore, not only be for the design of a safety function that will meet the risk reduction requirements but also to maintain it to these requirements throughout the operational phase.

Within ChemXpro, we ensure functional safety within the chemical industry using our practical experience in the application of the IEC 61511 standard during all phases of the equipment lifecycle. Our goal, and the goal of this standard, is to ensure that a properly engineered safety function is built and maintained within an asset management system that not only keeps the facility safe but also continues to improve it.

As you may expect from us, our approach is straightforward, understandable, reliable, and structured.

We can, therefore, typically provide the following engineering services:

  • Development and facilitation of SIL determination studies using standard methods such as LOPA or Fault Trees;
  • Generation of Safety Requirements Specifications;
  • SIL calculation and verification;
  • Generation of company-specific proof test procedures;
  • Conduct Functional Safety Assessments;
  • Provide customized training.

So how do we do it?


The design of a properly engineered safety function starts with the functional specification in terms of the needed risk reduction.

We have experience in the use and facilitation of various standard methods in the identification, classification, and ultimate assignment of the required risk reduction to the proposed or existing safety functions. Examples of the methods that we can use are: Layer of Protection Analysis, Fault Trees and Failure Mode and Effect Analysis. The selection of the correct methodology will usually depend on:

  • the severity of the hazard,
  • the complexity of the initiating events leading to the hazard and
  • the experience of the design/operations team with the technology.

There is not one generic approach to follow during this phase, and you will also have specific preferences on what methods to use and how the risks are ultimately assigned. We, therefore, take the time to properly consult with you in developing a custom execution plan that will meet your needs while also providing the necessary rigor in terms of quality before we start with the technical analysis.

At the end of the phase, we describe the functional requirements of the different safety functions that are identified throughout the process in a Safety Requirements Specification. We aim to provide a functional specification that covers all aspects of a robust design, which is the combination of reliability, availability, and maintainability. This document is extensively used and referenced during the subsequent phases of design and operation.


The functional requirements detailed in the previous phase are used for the detailed design, implementation, and final validation of the safety functions.

A safety function typically subdivided into separately engineered elements, broadly classified as sensors, a logic solver, and final elements. Together these elements must achieve the specified risk reduction or Safety Integrity Level (SIL). It requires a careful analysis of the hardware reliability, configuration, and the performance of the different elements during the operational lifetime.

It is essential to ensure that the safety functions are properly tested and validated against the original engineering requirements before being put into operation. It must also be established whether operations and maintenance have the necessary information, tools, and skills available.

Does this sound difficult? Yes, it can be – but we can help with this. We make use of our practical experience combined with specialized engineering software to confirm the risk reduction of the selected technologies. We also make useful recommendations in the case where the current design does not meet the minimum requirements. Lastly, we can assist in conducting functional safety assessments and 3rd party audits.


The safety function must be tested and maintained to the original engineering requirements during the operational phase. It requires continued focus to ensure that:

  • The design requirements are available and kept up to date;
  • Work procedures are correct, precise and followed;
  • Operations and maintenance are sufficiently trained and have the necessary tooling;
  • Essential performance metrics are captured, and any deviations are pro-actively rectified.
  • Modifications are correctly managed and integrate seamlessly with the existing facility.
  • The safety function is de-commissioned without incident when its use becomes redundant.

We acknowledge that you are in the best position to safely and efficiently operate your facility. Still, we have found that some specialist support is sometimes needed to help interpret the IEC 61511 specification or give insight to the latest best practices in functional safety. Maybe all you need is some assurance that your systems are indeed in place and working as effectively as it should. Please let us know how we can assist you with this. We thrive on being able to find customized solutions that best suit your business needs.

So in conclusion we would like to think that we can provide specialized and customized assistance to you throughout all aspects of the asset lifecycle.