The date has been set for the brand-new IEC 62368-1 safety standard to go into effect. As its December 20, 2020 deadline approaches, this article looks at the main principles behind the new standard, what it means for product certification, and how product manufacturers can best manage the transition.
More than a simple merger or name change, IEC 62368-1 2nd Edition is significant because it introduces a new, hazard-based perspective to product testing for ICT (Information and Communications Technology) and AV (Audio/Video) equipment in North America and the EU. Poised to supersede the outgoing IEC 60950-1 for ICT equipment and IEC 60065 for AV equipment, the new single standard is implementing fundamentally different engineering principles and terminologies.
A work in progress of IEC Technical Committee TC108 since 2002, the move to introduce IEC 62368-1 was prompted as the boundaries between ICT and AV equipment have become increasingly blurred over time, as new types of affordable products have appeared for use in small and home offices, and in-home entertainment. While the scope of the new standard is the same, the use of Hazard-Based Safety Engineering (HBSE) marks a shift away from the need to demonstrate that prescribed specifications have been met.
The single, harmonized standard aims to create a more future-proof document by requiring that manufacturers show known hazards have been considered and their products have been built to be safe for use in their intended environments. Furthermore, IEC 62368-1 expects to give product designers more flexibility in their designs and evaluations, keeping pace with technology without requiring frequent, expensive, and onerous revisions.
With the advance of new technologies, and with them, new markets, the single, harmonized standard intends to provide a clearer framework within which to evaluate the safety of new equipment. As such, all current equipment that falls within IEC 60950-1 and IEC 60065 will be encompassed by the new standard, with additional products set to be included within its scope. A list of product categories includes the following:
- Computing and networking products: servers, PCs, routers, notebook/laptop computers, tablets, plus their power supplies
- Consumer electronics: amplifiers, home theater systems, digital cameras, personal music players
- Displays and display units: monitors, TVs, digital projectors
- Telecommunication products: network infrastructure equipment, cordless and cell phones, battery-powered communication devices
- Office appliances: copiers, document shredders
- Various types of audio/video, information and communication technology equipment used in homes, schools, data processing centers, commercial and professional environments
In addition, the new standard is not just limited to products, but also relates, where applicable, to components and subsystems. Therefore, companies that source third-party subsystems like power supplies will need to establish whether the required product is certified to IEC 62368-1. Likewise, components that are fitted inside equipment, like chassis mount power supplies, are also subject to the standard, together with any external power supplies and adapters that are shipped alongside boxed equipment.
Hazards and safeguards
As mentioned above, the move to HBSE principles demonstrates a shift in focus for the new standard. HBSE is a field of safety science that has been gaining ground over the last 25 years, shifting product-safety legislation towards a performance-orientated way of thinking and making it more flexible and effective than prescriptive approaches. Its principles work to keep equipment users safe by identifying potentially hazardous energy sources that are capable of causing pain or injury to users and recommending the appropriate means of preventing those energy transfers from occurring. Its rationale can be summarized as follows:
- Identify energy sources used
- Measure energy levels they produce
- Determine whether source energy is hazardous
- Classify it accordingly
- Identify how energy is transferred to a body part
- Determine appropriate safeguarding measures
- Measure effectiveness of safeguards
HBSE represents hazards and safeguards as three-block models that explain the link between energy source, energy-transfer mechanism or safeguard, and the end user, as follows:
Figure 1: HBSE three-block model for safeguards and energy transfer (Image source: CUI Inc.)
As well as allowing for bodily injury, the new standard also applies the HBSE three-block measure to assess the potential for electrically caused fire, recognizing the need for a fuel to be present for ignition to happen. Furthermore, 62368-1 references all energy sources relevant to ICT/AV electrical equipment including electrical, thermal, chemical, kinetic, and radiated energy.
IEC 62368-1 standards classify the energy levels that a user might be exposed to as ES1, ES2, and ES3, with ES1 being the lowest category. A comparable rising scale is used when analyzing electrical-fire hazards and their means of prevention. This scale of energy levels helps designers establish the necessary safeguards needed for their product, including methods such as protective earthing, insulation, and fire-proof spaces. Likewise, the user him/herself is also categorized, this time by competence, as either an ‘ordinary person’, ‘skilled person’ or ‘instructed person’.
Figure 2: IEC 62368-1 energy level classifications (Image source: CUI Inc.)
Timeline to implementation
Change is coming and for companies that have not yet begun their own transition, now is the time to begin their preparations and make safeguards of their own.
The new hazard-based methodology around safety analysis aims to give designers greater flexibility to design safety measures in the context of their own products, while at the same time requiring thorough assessment to guarantee that those products are safe to use and cannot cause bodily injury or fire. This approach supports the introduction of new and innovative methods of construction and technology without first needing to be amended. This will help reduce the differences between published regional and national equivalents of the standard.
Fortunately for OEMs, IEC 62368-1 2nd Edition contains clauses designed to support companies in managing the transition from the legacy standards. These include helping them to decide how and when to certify their products to the new standard as well as how to manage their current inventory of subsystems and components that fall within 60950-1 and 60065.
Finally, regulators in the US and Europe have agreed to synchronize the date IEC 62368-1 comes into effect, providing an unambiguous, unified target for product vendors to work towards across these major worldwide markets. This has been a positive development for OEMs, giving them a little more time to put their new testing methods and documents in place.
By providing an explicit, harmonized date, product vendors know exactly where they stand, and on December 20, 2020, when the previous standards are withdrawn, they will be in a strong position going forward, delivering innovative products that are in full compliance. Thanks to CUI, the path toward compliance has been made easier with their range of IEC 62638-1 certified power adapters from 3 W to 250 W, ready to keep designers one step ahead of the transition.