Understanding Functional Safety Standards: A Guide to EN ISO 13849-1

Functional safety is a critical consideration in today’s industrial landscape. It ensures that machinery and systems operate safely, protecting both workers and assets. One essential standard that plays a pivotal role in achieving functional safety is EN ISO 13849-1. In this blog post, we will delve into the key aspects of EN ISO 13849-1, exploring what it is, its importance, and how it impacts industries worldwide.

What Is EN ISO 13849-1?

EN ISO 13849-1 is a European standard that deals with the safety of machinery. It is part of the EN ISO 13849 series, which includes various parts that offer detailed guidance on different aspects of machinery safety. This standard, in particular, focuses on the design and validation of safety-related control systems within machinery.

The Importance of EN ISO 13849-1

Safety Assurance: Provides a framework for assessing and improving the safety of machinery control systems. It helps ensure that these systems function reliably to prevent accidents and injuries.

Legal Compliance: Adherence to EN ISO 13849-1 is often a legal requirement in many countries, particularly within the European Union. Failing to comply can result in serious legal consequences.

Global Applicability: While it’s an EN (European Norm) standard, EN ISO 13849-1 is recognised worldwide as a benchmark for functional safety. Many non-European countries have adopted similar standards, making it a global necessity.

Key Components of EN ISO 13849-1

Performance Level (PL): PL is a measure of how appropriate a control system is to perform its safety function. EN ISO 13849-1 defines five PLs, from PL a (lowest) to PL e (highest). Selecting the appropriate PL is a crucial step in the design process.

Categories: This standard categorises the safety function by its resistance to faults and its subsequent behaviour in the event of a fault, which is achieved by the structural architecture of the system, fault detection and/or its reliability. The specification of the required category depends on the potential consequences of system failure.

MTTFd and DC: Mean Time To Dangerous Failure (MTTFd) and Diagnostic Coverage (DC) are key metrics used to evaluate the reliability of safety-related control systems. These metrics help in designing systems that minimise the likelihood of undetected dangerous failures.

Validation: The standard also addresses validation, requiring manufacturers to prove that their safety-related control systems meet the specified performance levels.

The Process of Achieving Functional Safety

Risk Assessment: The process begins with a thorough risk assessment. This involves identifying potential hazards, assessing their severity, and determining the required safety measures.

Design and Implementation: Engineers and designers then create a control system that meets the necessary PL and categories.

Validation and Testing: The control system is validated through testing and analysis to ensure it meets the required safety performance levels.

Documentation: Keeping accurate records of the design, implementation, and validation process is essential to prove compliance with EN ISO 13849-1.


EN ISO 13849-1 is a crucial standard that underpins functional safety in machinery and industrial systems. Understanding and complying with this standard is essential for manufacturers, system integrators, and users of machinery to ensure a safe and efficient working environment.

It’s worth noting that compliance with this standard often requires specialised knowledge and expertise in safety engineering. Therefore, it’s common practice to seek the guidance of professionals and experts in the field to ensure that safety-related control systems meet the necessary performance levels and reliability criteria. In doing so, industries can not only meet legal requirements but also create safer workplaces for their employees and stakeholders.

We hope this blog post has provided valuable insights and information on machinery functional safety. If you have any questions, need further assistance, or would like to explore related topics in more depth, please feel free to reach out to us. Your feedback and inquiries are essential to us, and we are here to support you on your journey of knowledge and exploration in the field of machinery and safety compliance. Let’s continue the conversation and work together to achieve your compliance and safety goals.

Share this post

Let's work together

For a free initial consultation simply book an appointment via our meeting system by clicking below.

Eight (and a half) things that compliance and machinery safety consultants may not tell you... Knox Thomas

Eight (and a half) things that compliance and machinery safety consultants may not tell you…

Read more

Navigating Machinery Safety: Understanding the Difference Between Safe and Compliant Machines

Read more
Chainsaw Safety - Knox Thomas

Understanding Perceived Risk in Machinery Safety: Petrol vs Electric Chainsaws…

Read more
What is PUWER? A guide by Knox Thomas

What is PUWER?

Read more