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

For C, market / system is NEC; stated equivalent is IIB; applies to is Ethylene, recorded from its source on 2026-08-11.

- **Designation:** C _(verified: appears in the quote below)_
- **Market / system:** NEC
- **Stated equivalent:** IIB _(verified: appears in the quote below)_
- **Applies to:** Ethylene _(verified: appears in the quote below)_

## What the source says

> C (Ethylene) | IIB

## Source

- https://www.inframena.com/hazardous-area-classification-equivalency-guide/

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/).