Functional Safety (EN 13849)

Jul 20, 2023

BS EN ISO 13849-1 specifies the requirements for the design and implementation of machine safety related parts of control systems (SRCS) and is applicable where control systems contribute to the risk reduction on the machine


Where there is a failure of that SRCS to provide risk reduction due (for example, a failure of hardware) would result in an immediate and unacceptable risk. The guidance provided gives a method for estimating the level (Performance Level) of risk reduction required by the SRCS but this the validation of the overall solution requires a knowledge of the protective devices and final switching devices related to each hazardous movement or uncontrolled release.

Our Services

We can provide the level of support required depending upon your needs and the stage of the project you are working on. As a part of a design risk assessment process in line with BS EN ISO 12100 2010 the hazards on the machine will be identified early on and, where practicable, risk reduction objectives will be met using inherent safe design measures. However, in some cases risk will remain and it is these risks that we can look to use Safety Related Control Systems in order to reduce the risk to an acceptable level.

Spiers can provide support from Design Risk Assessment (DRA) to verification and validation of the SRCS.

How Function Safety Relates to a Normal PUWER Inspection

A normal PUWER inspection will consider compliance with EN 13849 and other related standards but only so far as is reasonably practicable to support a suitable and sufficient risk assessment. This is not the same level of detail and due diligence that must be demonstrated during a machine CE conformity assessment.

It is not possible in the time allowed to address every point in EN 13849 part 1 and 2 for the entire Safety Related Control System (SRCS) during the normal time allowed for a PUWER inspection. Therefore, with a focus on major injury risks and those that are considered most likely the inspection will determine whether the current arrangement complies with the basic safety principles of EN 13849 and consider other B type standards to take a position on the suitability of the SRCS. This judgement is made by the competent person completing the PUWER inspection at the time.

Article Categories
Browse articles from our other categories