What is functional safety?
Functional safety can be defined as the absence of any unreasonable risk caused by hazards that could result due to malfunctioning practices.
This requires the management of different operator errors, software errors, hardware failures, and environmental fluctuations. Functional safety at its core depends on the continuous operation of safety-related systems that detects and responds to a problem. Owing to this, it can be said that functional safety is actively responsible for preventing the failure of a system that could harm people and property.
To attain functional safety, developers and organizations certify a system as compliant with the requisite functional safety standard.
The State of functional safety in Industry 4.0
Industries of the modern age are embracing a change that was never seen before. A wave of digital transformation is replacing more and more mechanical and electrical parts changing the way all the elements and systems are used. Moreover, these systems are bringing in a new set of networking, interactive, and safety requirements. This also combines different data and physical elements with information technology and communications. A connected environment that uses integrated modules to deliver critical data, to process real-time information, all to ensure the industrial ecosystem moves on from working in silos to a connected system. This change not only enhances the manufacturing processes but creates a digital value chain that is extremely beneficial for organizations. Helping organizations attain functional safety in this fast-moving digital world is the IEC 61508 that looks at safety-related electronic, electrical, and programmable electronic systems.
To implement functional safety in Industry 4.0, it must include:
Interoperability: An ecosystem where devices, machines, people, and sensors can connect and communicate with each other.
Transparency: The systems must create a virtual copy of the environment using sensor data to contextualize and define information.
Assistance: An ecosystem where the systems and humans support each other in solving problems, making decisions, and to assist each other in having a safe environment.
Decentralization: A system where the cyber-physical systems can take and implement simple decisions by themselves, reducing human interference to remove biases in decision making.
Importance of Functional Safety
Every system and process must embrace failures. These could be hardware or software related failures that could happen unpredictably during the lifetime of a system. The most common causes of failures include the likes of:
- Random systematic failures
- Human errors
- Fluctuation in power supply
- Environmental factors that include weather, electromagnetic interference, or mechanical interferences
Functional safety mechanisms look at mitigating any risk that could be caused by any of these failures. It is done by defining the safety integrity level (SIL) of a system or process. In simple words, SIL can be defined as the measurement of performance that is required for a safety instrumented function (SIF). Systems that comply with functional safety are equipped to prevent any dangerous failures or to control them whenever they occur. Functional safety also helps in designing systems that can execute the required set of functions correctly, even in the case of being misused. Moreover, functional safety pushes manufacturers and organizations to identify all the unintended behaviors that could be hazardous, by providing the required risk assessments.
What you need to know about functional safety requirements
Simply put, functional safety is all about ensuring that the system and process work safely and continue to do so even in the case of a mishap. Different industries have different standards and expectations to comply with, based on the equipment and ancillary software(s) and components that are being used. In order for companies to meet the functional safety requirements, they must follow a 5 -step process. Here are the 5 steps:
Determine safety function and integrity requirements
At this stage, companies define the required safety function and the level of risk mitigation that is required to attain the required safety function. To define these, companies look at the testing and maintenance of the specified functions and their functionality in the event of a failure to define the design process.
Design the right system
Owing to the requirements, a system must be rightly designed to comply with the functional safety requirements, the specifications, and the relevant standards. This makes sure that the system will perform the required safety function reliably, ensuring a robust and safe system.
Verify the designs
In this step, the designs are critically reviewed against all the requirements. This is done to analyze the reliability to see if the required safety integrity levels are attained. Verification of the designs also helps in confirming that all the requirements are achieved, from reducing the redundancy, to attaining the appropriate diversity to having a robust system.
Certify the designs
Once the designs are verified, it is necessary to validate the verification process too, by looking if the required standards were adhered to. This process starts by overviewing the entire chain of events and subsequently moves into a more detailed process.
Functional safety requirements must be adhered to even after the designs are verified and validated. The process of validation is just the first step wherein henceforth, the system must be installed, tested, monitored, and maintained to perform at the intended levels.
Functional safety has become increasingly important for every manufacturer. More so, with the integration of hardware and software systems, there is bound to a growing dependence on these standards. While its relevance has seen exponential growth, it is time the world sees it as an integral part of every organization, irrespective of the sector. Click to know more about functional safety training and certification.