Functional Safety

Functional Safety


Since decades, the vital functions of the plant management are handled by automation systems of measurement, protection, control, monitoring and supervision, made with programmable electronic technologies. These systems are typically distributed within the plants, and are interconnected by communication networks by means of local and remote connections which, in many cases (e.g. electrical system) can extend on very long distances. In this framework plants depend more and more on the reliability and functionality of their communication infrastructure and of their automation systems and subsystems. If some of the functions involve safety issues, the reliability of the systems that perform these functions must be strongly validated and must grant adequate safety levels. In other words it is necessary to manage the so-called functional safety of the system or subsystem in accordance to the "life cycle approach".

Functional safety is defined as the part of the overall safety of the equipment or process and control systems associated with them which depends on the correct functioning of the electrical, electronic and programmable electronic safety-related applications or other technological systems for safety applications.


The technical standard of reference is the standard EN 61508 from which derive all the technical standards for the regulation of specific matters.

Functional safety includes control of random hardware failures, which can be quantified in terms of failure rates and then evaluated, and the systemic failures, which cannot be quantified, and require a strict control of the phases of design but also the operational phases of the product (life cycle approach).

EN 61511 is the specification standard for the process industry, including in particular the chemical, refining, oil drilling and the production of paper, as the production of electricity. This standard provides the guidelines for determining the level of integrated safety (SIL) of a Safety Instrumented System (SIS).

The review of the safety standard of the electrical equipment of machines EN 60204-1 led to the repeal of EN 954-1 and permanent introduction of UNI EN ISO 13849-1 and EN ISO 62061, through which it is possible to define the safety category and the level of reliability of control systems related to safety with the possibility of referring also to the programmable electronic systems for the management of the safety functions of a machine.


  • Design and engineering of Safety Instrumented Systems (SIS) according to FUNCTIONAL SAFETY Regulations (e.g. EN 61511)
  • Analytical determination of the Probability of Failure on Demand (PFD) of the Safety Instrumented Function (SIF) for SIS architectures for 1oo1, 1oo2, 2oo2, 2oo3
  • Reliability analysis of components and safety systems in relation to the parameters of reliability
  • Training
  • Project Management for "Life Cycle approach".


Tower 42, 25 Old Broad Street
London, EC2N 1HN, UK

Tel. +44 020 787 740 82

Tel. +4402078774082+4402078774082



DESC allows to simulate evolution of dust explosion in complex geometries ...


Functional safety is defined as the part of the overall safety of the equipment or process ...


Risk prevention is one of the primary objectives of the assessment of the risks ...


Civil Defence Exhibition & Conference 2015

Etea Sicurezza Group is glad to announce its participation to the Civil Defence Exhibition & Conference in Doha