UL 60079-0 2020-04 PDF

Full title and description

UL 60079-0:2020 — Explosive atmospheres — Part 0: Equipment — General requirements. This UL standard is an IEC-based adoption that specifies general construction, testing and marking requirements for electrical equipment and components intended for use in explosive atmospheres, and includes UL national differences and redline revisions issued April 15, 2020.

Abstract

This document provides the general requirements applicable to Ex equipment and Ex components for use in hazardous (classified) locations (Zones 0, 1, 2 and Zones 20, 21, 22). It covers design and construction principles, tests, marking, documentation and information required for safe operation and certification. The UL edition incorporates IEC 60079-0 technical content with US differences and specific UL supplementary requirements (including certain wiring and documentation clarifications).

General information

• Status: Active standard (UL publication/adoption of IEC requirements; maintained with revisions/redlines).
• Publication date: April 15, 2020 (UL redline/revision issued April 15, 2020; original UL edition based on IEC ed.7 is dated 2019).
• Publisher: Underwriters Laboratories Inc. (UL).
• ICS / categories: 29.260.20 — Electrical apparatus for explosive atmospheres.
• Edition / version: Edition 7 (IEC-based adoption); UL redline/revision published April 15, 2020 (UL has continued to issue subsequent revisions/redlines).
• Number of pages: Approximately 180 pages (publisher PDF/page count as catalogued for the 2020 UL release).

Scope

Specifies the general requirements for design, construction, testing, marking and documentation of electrical equipment and Ex components intended for use in explosive atmospheres, including criteria that relate equipment protection levels (EPLs) to Zone classifications and the application of protection concepts (e.g., intrinsic safety, flameproof/enclosure, increased safety, encapsulation, pressurization). The scope aligns with IEC 60079-0 while including UL national differences where applicable.

Key topics and requirements

• General construction and design requirements for Ex equipment and components (mechanical, electrical and material considerations).
• Type-tested and routine test procedures, including tests relevant to ignition prevention and containment of explosions.
• Marking, labeling and required documentation (including instructions for use, installation, maintenance and limitations).
• Relationship between Equipment Protection Levels (EPLs) and Zone classification; requirements for hazardous-area classification references.
• Protection concepts and construction types: intrinsic safety (ia/ib), flameproof (d), increased safety (e), encapsulation (m), pressurization (p), and others as defined in the IEC/UL framework.
• UL national differences and supplementary requirements (for example, clarifications on factory-wiring between enclosures and allowance for electronic-format instructions introduced in the 2020 redline).

Typical use and users

Used by equipment manufacturers, design engineers, testing and certification laboratories, compliance officers, and companies installing or maintaining electrical equipment in hazardous locations (oil & gas, chemical processing, mining, grain handling, pharmaceuticals, marine, and other industries with explosive-atmosphere risk). Regulators and inspection bodies reference the standard when assessing compliance with hazardous-location requirements.

Related standards

Directly related to IEC 60079-0 (and its corrigenda), and part of the wider IEC/UL 60079 series (for example UL/IEC 60079-1 for flameproof enclosures, UL/IEC 60079-11 for intrinsic safety). It is commonly used in conjunction with national electrical codes and regulations addressing hazardous (classified) locations, such as the National Electrical Code® (NEC, NFPA 70) in the United States.

Keywords

explosive atmospheres; hazardous locations; Ex equipment; Equipment Protection Level (EPL); zones 0/1/2/20/21/22; flameproof; intrinsic safety; increased safety; encapsulation; pressurization; certification; UL adoption; IEC 60079-0.

FAQ

Q: What is this standard?

A: UL 60079-0:2020 is Underwriters Laboratories’ IEC-based standard that sets the general requirements for electrical equipment and components intended for use in explosive atmospheres (hazardous locations). It brings IEC 60079-0 requirements together with UL national differences.

Q: What does it cover?

A: It covers general design, construction, testing, marking and documentation requirements for Ex equipment and components, and defines how protection concepts and EPLs relate to zone classification. It does not replace the component-specific parts of the 60079 series (those parts detail requirements for particular protection types).

Q: Who typically uses it?

A: Manufacturers, design and safety engineers, test houses and certification bodies, regulators, and facility engineers responsible for selecting and installing equipment in hazardous locations.

Q: Is it current or superseded?

A: The UL 60079-0 adoption with the April 15, 2020 redline is a current historical release of the standard; UL has continued to maintain and issue subsequent revisions/redlines (UL records show later updates/revisions). Users should verify they hold the latest UL/ANSI publication or redline when applying the standard.

Q: Is it part of a series?

A: Yes — it is Part 0 of the IEC/UL 60079 series. Part 0 defines the general requirements; other parts in the 60079 series provide requirements for specific protection methods and equipment types (for example Parts 1, 11, 15, etc.).

Q: What are the key keywords?

A: Explosive atmospheres; Ex equipment; hazardous locations; zones; EPL; intrinsic safety; flameproof; increased safety; encapsulation; pressurization; UL adoption of IEC standards.