# A — Certification marks and hazardous-area classifications: cross-market equivalences For A, stated equivalent is IIC; applies to is Acetylene, verified against its source on 2026-08-11. - **Designation:** A _(verified: appears in the quote below)_ - **Stated equivalent:** IIC _(verified: appears in the quote below)_ - **Applies to:** Acetylene _(verified: appears in the quote below)_ ## What the source says > A | IIC | Acetylene | <0.50 mm ## Source - https://exknowledge.com/pages/nec-500-vs-atex-iec.html 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/).