# D — Certification marks and hazardous-area classifications: cross-market equivalences For D, stated equivalent is IIA; applies to is Methane, propane, gasoline, verified against its source on 2026-08-11. - **Designation:** D _(verified: appears in the quote below)_ - **Stated equivalent:** IIA _(verified: appears in the quote below)_ - **Applies to:** Methane, propane, gasoline _(verified: appears in the quote below)_ ## What the source says > D | IIA | Methane, propane, gasoline | >0.90 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/).