What is Functional Safety?


In public spaces, factories, offices or homes; we are surrounded by a growing number of electrical and electronic devices and systems. Many of them could cause harm to humans, other animals or the environment if they did not have built-in safety mechanisms that are activated exactly when necessary to reduce potential risks to a tolerable level.

Safe function of a device or system

Functional Safety is part of the general safety of a system or equipment and generally focuses on electronics and their associated software. Examines safety aspects related to the function of a device or system and ensures that it functions correctly in response to orders receiving. From a more generic point of view, Functional Safety identifies potentially dangerous conditions, situations or events that could result in an accident that could harm someone or destroy something. Activates and mechanizes corrective or preventive actions to avoid or reduce the impact of an accident.

For example, when we enter a train from the platform, we want the doors not to close unexpectedly without warning, but to stay open long enough to be able to enter the train and that, when they begin to close, there are acoustic luminous warnings . Putting more exotic cases, the same happens when we slip off a jet ski or overturn with a lawnmower: the safety mechanisms incorporated in these equipments will turn them off in time to prevent us from being run over and / or injured.

The complex concept of risk tolerance

The objective of Functional Safety is to reduce risk to a tolerable level and reduce its negative impact; however, and you always have to take it into account and accept it, there is no zero risk. Functional Safety measures risk based on two basic parameters: the probability of a specific event occurring and its severity; in other words: how much damage could it cause.

Electrical, electronic, or programmable electronic (E / E / PE) systems perform a multitude of safety functions. The challenge is to design safety systems in such a way that dangerous failures are avoided or controlled when they arise: AVOIDING or PREVENTING RISKS and CONTROLLING THEM WHEN THEY APPEAR: This is the main concept of Functional Safety.

These systems are often complex, making it impossible in practice to fully determine all potential failures, but a robust validation process as extensive and detailed as the application requires is essential to rule out as many as possible.

Functional Safety is everywhere

The concept applies to everyday life and every industry you can think of. Proof of them is that Leedeo Engineering Engineers have executed projects in more than a dozen industries. It is critical, for most security-related systems. The oil and gas industry, nuclear plants, the consumer goods manufacturing sector, the automobile, medical devices and, of course, transportation, rely heavily on Functional Safety to achieve safety in areas where operation equipment can lead to hazards.

Automotive: some examples

In the car, Functional Safety ensures, for example, that the airbags deploy instantly during the impact to protect us against an accident, but not when you are simply driving. Check the fuel injector to make sure that our car does not accelerate when we did not give the order; ensures that the ABS brakes engage when necessary and do not engage when not requested. When our children havenhands on the power rear window you are closing, Functional Safety protocols ensure that this resistance prevents the window from cutting your fingers. Functional Safety guarantees the correct operation of all the electronics that work in a car and its control software.

Transportation: some examples

When boarding a train, metro or cable car, Functional Safety ensures that the doors are closed before the vehicle exits and that they are not opened while in motion. It also ensures that the rail signaling system enables the safe movement of trains through the rail infrastructure.

Aviation is among the safest industries in the world and applies Functional Safety in many areas, including, for example, the automated flight control system. The two-axis autopilot system controls the pitch and roll of the aircraft and controls the heading and altitude, which are programmed to respect certain Functional Safety parameters, activating alarms and other measures when they are violated.

Health care : some examples

In the healthcare field, the presence or absence of Functional Safety protocols can mean the difference between life and death for a patient. In addition to the electrical or mechanical aspects that affect safety, Functional Safety ensures that a given appliance works correctly in response to inputs. For example, if an infusion pump is malfunctioning, Functional Safety protocols will ensure that alarms are activated to signal malfunction and, if relevant, that the pump is deactivated to protect the patient from harm from overdosing. A different set of safety protocols ensures that a patient undergoing radiation therapy for cancer only receives exactly the scheduled dose of gamma radiation, nothing more.

Manufacturing : some examples

Functional Safety is the best mechanism to reduce the risks inherent in dangerous industrial processes both within a factory or chemical plant. An automatic valve closing mechanism will ensure that hazardous chemicals are mixed in exactly the required amounts. A safe crane load indicator will prevent the overload from collapsing the crane and killing innocent workers or bystanders. Sensors or laser barriers will automatically shut down a robot when a human or object enters its range of activity, preventing injury or potentially costly damage to machinery. A pressure valve will open or close precisely when electronically instructed to do so. When such safety devices do not function as they should, for example while drilling for oil in deep water or during filling of a chemical tank, major disasters can occur.

Power generation: some examples

Wherever there is electricity, Functional Safety will surely be very close. When hurricane force winds hit, a wind turbine must be able to detect it and enter special operating modes that guarantee the integrity of the elements of the mechanical system, which could lead to damage or destruction of different systems due to excessive twistsin terms of speed. When the vibration levels in a gas turbine exceed a certain limit, an automatic shutdown mechanism will prevent its disintegration and prevent injury to the surrounding workers.

Generically and transversal in any industry, therefore, many systems are designed to automatically prevent dangerous failures or to control them when they arise. Such failures can arise, for example, from:

  • Random or systematic hardware or software failures.
  • Human error.
  • Environmental circumstances such as temperature, climate, electromagnetic interference or mechanical phenomena.
  • Loss of power supply or other disturbances.
  • Incorrect system specifications both hardware and software.
  • Omissions in the specifications of the security requirements (for example, lack of implementation of all relevant security functions in line with the different modes of operation).

So-called electrical, electronic or programmable (E / E / PE) safety-related systems cover all parts of a device or system that carry out automated safety functions. This includes everything from sensors to control logic and communication systems to final actuators, including critical human operator actions and environmental conditions .

Many safety-related systems that would have used electromechanical technology now use programmable electronics. Devices such as microcontrollers, programmable logic controllers (PLCs), and digital communication systems (eg, bus systems) are part of this trend. Clearly, semiconductor technology, such as application-specific integrated circuits (ASICs), microprocessors, and smart sensors, transmitters, and actuators, are increasingly being integrated into products and systems. From a conceptual point of view, it is important to understand that the great difference between these teams and those that formed security systems until the middle of the 20th century, is that they incorporate software programming. This is one macro trend in product and system development, which will only increase and increase in its next years.

Functional Safety and the people who interact with the systems we design

As more and more machines are integrated into industrial automation and logistics, mobility and healthcare processes, the need to ensure safe procedures for people working and interacting with machines increases. The Internet of Things ( IoT ), big data, advanced robotics, and especially artificial intelligence (AI) are transforming the connection between electrotechnical systems and people. While AI can dramatically improve efficiency in, for example, workplaces and can increase human performance capabilities, the question arises: will machines become super-smart and lead humans to lose control eventually?

Although the likelihood of such a scenario with possible additional risks is up for debate, we know that unintended consequences for humans always arise when new technology is introduced. Consequently, more than at any time in the past, it is essential to ensure that human security is at the center of the new man-machine relationship.

In parallel, since humans continue to play an important role in causing accidents, whether in the design and planning stages or during the execution of work, any effort to improve safety in man-machine collaboration must focus specifically in human behavior: the famous human factor. And while the future can hardly be predicted with precision, technological, social and legislative mega trends will clearly impact the future of work and safety.

In a very summarized way we believe that ...

  • Social goals must be established that aim to achieve both safety and efficiency, moving from a security model based on the separation of man and machine to one in which security is achieved through man-machine cooperation.
  • Consideration should be given to the possibility that humans may not be the "smartest" component in a new human-machine collaboration system. A new concept of security should be developed through the development of technology and the reconfiguration of man's place in the system.
  • Measuring security outcomes has been a key part of security management systems for many years, with a focus on incident statistics. However, a more proactive and forward-thinking approach could be taken by introducing "leading" indicators into the calculation.
  • Standards bodies must broaden and deepen their holistic approach to security. This will require incorporating not only traditional technical expertise, but also knowledge gathered from the fields of security psychology, sociology, and human behavior. In other words, it is recommended that, In the development of future safety standards, clear attention is paid to non-technical factors.

At Leedeo Engineering , we are specialists in the implementation of models and processes to improve the security of organizations, including the Culture of Security . Do not hesitate to contact us for more information about our services. Contact >>   

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