Designing for IEC 62368-1: What Changed from 60950 and 60065

IEC 62368-1 is the audio/video, information technology, and communication technology equipment safety standard that replaced both IEC 60950-1 and IEC 60065. Since the transition deadline passed, all new product submissions must comply with 62368-1. Understanding its hazard-based approach is essential for hardware teams.

What Changed: Prescriptive vs. Hazard-Based

IEC 60950-1 and 60065 were prescriptive standards — they told you exactly what to do. IEC 62368-1 takes a hazard-based safety engineering (HBSE) approach. Instead of prescribing solutions, it identifies energy sources and safeguards required to prevent those energy sources from causing injury. This gives designers more flexibility — but requires a deeper understanding of the safety rationale behind each requirement.

Energy Source Classification

The standard classifies energy sources into three levels based on the potential for injury:

• ES1 — Not capable of causing injury under normal or single-fault conditions (e.g., SELV circuits below 42.4V peak AC or 60V DC)
• ES2 — Capable of causing a painful but not dangerous shock under normal conditions; safeguards prevent injury under fault
• ES3 — Capable of causing a dangerous or lethal shock; requires reinforced safeguards and physical barriers

Key Design Implications

For most consumer electronics operating from mains input, the critical design tasks under 62368-1 are:

• Classifying all accessible parts and internal circuits against ES1/ES2/ES3
• Ensuring primary-to-secondary creepage and clearance distances meet the requirements for the working voltage and pollution degree
• Verifying that PS2 and PS3 power sources (thermal energy) are controlled with appropriate safeguards
• Documenting the safeguard structure — 62368-1 audits focus heavily on the design rationale