Since the PDF is a reference document, use this workflow when you hit a design roadblock:

Scenario 1: Determining Trace Width for Power

Scenario 2: Determining Safety Spacing (Creepage/Clearance)

The standard is copyrighted by IPC — Association Connecting Electronics Industries. Purchase directly from:

If you open the IPC-2221 PCB design PDF and skip directly to Section 6, you will find the "Electrical Clearance" tables. This is the section that prevents arcing and short circuits.

IPC-2221 ("Generic Standard on Printed Board Design") is a flagship publication from the Association Connecting Electronics Industries (IPC). It establishes the generic requirements for the design of organic printed boards and their forms of assembly.

The standard is "generic" because it applies to all types of rigid and flexible PCBs, regardless of their end-use. It acts as the "umbrella" document for a series of more specific standards (such as IPC-2222 for rigid boards and IPC-2223 for flex boards).

Universities with ABET-accredited EE programs often have access to the IPC Educational Portal. Professors can provide the PDF to students for free under academic license.