Safety and functional safety
Safety is defined as the freedom from unacceptable risk of physical injury, and it is an integral aspect of all IEC work.
Electricity is inherently dangerous and electrotechnical equipment represents many risks that require mitigation. Those can be caused by electric shock, hot surfaces, moving parts or hazardous substances, to name but a few. They can impact people, critical infrastructure, economies or the environment. The IEC has a dedicated technical advisory committee on safety (ACOS) which guides and coordinates IEC work on safety in standardization and together with conformity assessment helps ensure that safety issues are properly addressed.
With the expansion of intelligent systems such as robotics, the internet of things or artificial intelligence, new and complex safety requirements are emerging. The increasing presence of machines in factories, logistics, mobility or healthcare, require safety procedures to protect the people interacting with them.
Safety in the future
Automatically reduce the level of risk in a device or system
At home, at work or in public spaces, we are surrounded by an increasing number of electrical and electronic devices and systems. Functional safety focuses on electronics and related software and activates built-in safety mechanisms to reduce potential risks that could harm somebody or destroy something to a tolerable level.
The sensors in automatic doors ensure that they open fast enough and close safely behind you. The detection of smoke by a sensor triggers the activation of a water sprinkler system inside an apartment building. An overflow valve is activated when a certain level of liquid or pressure has been reached.
The IEC 61508 series provides functional safety standards for the lifecycle of electrical, electronic or programmable electronic (E/E/PE) systems and products. It addresses those parts of a device or system that perform automated safety functions including, for example, sensors, control logic, actuators and micro-processors.
IEC 61508 allows for the development of a uniform technical approach that can be applied to all safety systems in electronics and related software. It is a horizontal standard applicable across a wide range of sectors.
The standard requires the analysis of the potential risks or hazards of a given system or device. It provides categories to determine the level of likelihood of a potential hazard and the consequences should it occur. IEC 61508 defines four safety integration levels (SIL) to indicate the degree to which a system will meet its specified safety functions.
Hazard based safety engineering
Hazard-based safety engineering (HSBE) is a methodology used in the development of safety standards.
Safety considerations are an integral part of the design process. Risks must be identified and managed at the early stages of product development. Due to the integration of electronic devices, audio, video, IT and communication technologies, hazard-based safety engineering (HSBE) has become increasingly necessary.
With HSBE, potentially hazardous situations are clearly identified and safeguards are put in place to increase product safety. Since safety requirements are outcome-based rather than prescriptive, HSBE which is part of IEC 62368-1, can be applied to a wide range of systems and devices.