# ta / tb / tc — Certification marks and hazardous-area classifications: cross-market equivalences

For ta / tb / tc, meaning is Enclosure; governing standard / law is EN/IEC 60079-31, verified against its source on 2026-08-11.

- **Designation:** ta / tb / tc _(verified: appears in the quote below)_
- **Meaning:** Enclosure _(verified: appears in the quote below)_
- **Governing standard / law:** EN/IEC 60079-31 _(verified: appears in the quote below)_

## What the source says

> Enclosure - ta / tb / tc EN/IEC 60079-31

## 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/).