platform-guideline checked

EPA Page Not Found web standard

Defines page not found pages for broken links and requires a clear page title, a way to find information, homepage or search links, domain homepage link, and additional helpful customer information.

Open source

Pattern Decisions This Source Supports

Pattern Supported decision Required contract Claim note
Page not found page Choose page not found page when the requested route, page, file, object URL, or deep link does not resolve to a valid destination. The page loads as a stable destination instead of redirecting users without explanation. EPA requires clear page-not-found title content, a way to find information, homepage or search links, and other helpful information.

Evidence Role

This source is treated as platform-guideline evidence. Use it to validate the decision rules above, not as a visual style reference.

Publisher: United States Environmental Protection Agency. Last checked: .