How International Standards are making our lives safer.
A computer that heats up excessively and burns the skin. A mobile phone charger that catches fire when plugged into the wall. A remote control with easy access to a coin battery that a small child can swallow. These are just a few examples of potential dangers that could have been lurking in our household devices. Luckily for us, Standards exist to make sure that products are safe to use.
A safety science discipline introduced over 25 years ago, hazard-based safety engineering (HBSE) is a methodology used in the development of safety Standards.
With the HBSE approach, potentially hazardous energy sources are identified clearly and safeguards put into place in order to mitigate the hazard and make a safe product. As a result, it is possible to apply HBSE principles to a broad range of products since the requirements are performance-based rather than prescriptive. This approach to safety Standards has become increasingly necessary with the development of electronic devices that merged audio video technologies with IT and communications technologies.
The convergence of technology is also reflected within the IEC standardization structure. The IEC set up a new Technical Committee (TC) 108 with the responsibility of developing safety Standards for electronic devices in the areas of audio/video, information technology and communication technology. It merged the work areas covered by TC 92 (audio/video and electronic equipment for household use) and TC 74 (data processing equipment).
TC 108 developed IEC 62368-1 based on the HBSE methodology of a three-block model for safety. New terminologies are introduced, such as ‘energy sources’ and ‘safeguards’ to align with HBSE concepts. The first edition was published in 2010 and replaced by a second edition in 2014. A third edition is expected to be published in mid- to late 2018.
IEC 62368-1 is performance oriented, with the flexibility to be applicable to a wide range of products, but with specific requirement and compliance criteria. Safety considerations are an integral part of the design process with risks identified and managed in the early stages of product development.
With IEC 62368-1, energy sources are identified and classified into three categories based on their effect on the body or on combustible material.
|Effect on body||Effect on combustible material|
|Class 1||Not painful but may be detectable||Ignition not likely|
|Class 2||Painful but not an injury||Ignition possible|
|Class 3||Injury||Ignition likely|
The necessary safeguards to protect against the energy source are then identified and put into place. The effectiveness of the safeguards are then qualified using compliance criteria. However, it is not a Standard based on the risk analysis of individual products.
When first introduced, IEC 62368-1 was a new type of Standard, based on a different methodology. While IEC 62368-1 was not a merger of the existing product safety standards, IEC 60065 and 60950-1, also developed by TC 108, it will eventually replace them. Mandatory implementation is expected by June 2019 in North America and the end of 2020 Europe.
For further details, UL developed a presentation with an overview of the Standard.