# AEx d — Certification marks and hazardous-area classifications: cross-market equivalences

For AEx d, market / system is US; stated equivalent is Zone 1; meaning is Flame Proof; applies to is Class I; governing standard / law is ISA 60079-1, verified against its source on 2026-08-11.

- **Designation:** AEx d _(verified: appears in the quote below)_
- **Market / system:** US _(verified: appears in the quote below)_
- **Stated equivalent:** Zone 1 _(verified: appears in the quote below)_
- **Meaning:** Flame Proof _(verified: appears in the quote below)_
- **Applies to:** Class I _(verified: appears in the quote below)_
- **Governing standard / law:** ISA 60079-1 _(verified: appears in the quote below)_

## What the source says

> Flame Proof AEx d US Class I Zone 1 ISA 60079-1

## Source

- https://www.euroswitch.com/wp-content/uploads/euroswitch-hazardous-area-guide_V6.pdf

Last verified: 2026-08-11. Review by: 2027-08-11.
Part of [Certification marks and hazardous-area classifications: cross-market equivalences](https://referencesource.org/certification-standards-equivalence/).