Explosion-Proof AMR Selection: What Buyers Must Resolve Before Choosing in ATEX/IECEx Environments

Start with Hazardous Area Classification

The starting point for explosion-proof AMR selection is not looking at robot specs. It is your facility’s hazardous area classification.

Hazardous area classification is determined by a process safety engineer based on the frequency and duration of combustible substances (gases, vapors, dusts) present at the site. It defines which areas have explosion risk and the risk level — not what the robot can do.

Discussing “can this AMR be explosion-proof?” before completing area classification is meaningless. You need to know which zone the robot will operate in, what level that zone is, and what combustible substances are present — then match equipment requirements.

Area classification framework (refer to ATEX directive 2014/34/EU and IEC 60079-10-1/-10-2 for definitions; national regulations may also apply):

Zone definitions and classification methodology are specified in the relevant standards — this table is a summary. A process safety engineer must perform the actual area classification per the applicable standards.

Key judgment: Does your AMR route pass through different zones? If the route extends from Zone 2 into Zone 1, the equipment must meet Zone 1 requirements. If the route only operates in Zone 2, Zone 1-level equipment is not needed — but you must confirm the route will not be upgraded due to process changes.

ATEX and IECEx Are Not Product Feature Labels

Many buyers understand “ATEX certification” as a robot feature — like “does it have Wi-Fi?” This is a fundamental misunderstanding.

ATEX is an EU directive (2014/34/EU) defining legal requirements for equipment used in potentially explosive atmospheres. IECEx is the IEC’s certification system, technically similar to ATEX but with broader international scope. They are not “feature labels” — they are compliance systems covering the following complete chain:

• Equipment classification: Equipment group (I = mining, II = surface industry), category (1 = Zone 0/20, 2 = Zone 1/21, 3 = Zone 2/22) — refer to ATEX directive and IEC 60079-0 for definitions
• Gas group: IIA, IIB, IIC — equipment must cover the target gas; refer to IEC 60079-0 for gas group classification
• Temperature class: Equipment surface max temperature must not exceed the ignition temperature of combustible substances in the environment — refer to IEC 60079-0 and certification documents for temperature class values
• Protection type: Flameproof enclosure (d), intrinsic safety (i), increased safety (e), pressurization (p), encapsulation (m), type n — each has different engineering principles and limitations; refer to the relevant IEC 60079 series standards and certification documents for applicability
• Complete equipment vs. components: What does the certification cover — the whole machine, motors, sensors, or wiring?

Ask the supplier for the explosion-proof certificate and confirm: what equipment scope does the certificate cover? Is it whole-machine or component certification? Do the gas group and temperature class cover your environment? Is the certificate still valid?

Gas Zones vs. Dust Zones

Gas and dust explosion protection use different technical principles and cannot be interchanged.

Gas environments: Combustible gas mixes with air to form an explosive atmosphere. Protection core is preventing electrical equipment from creating ignition sources (arcs, sparks, hot surfaces). Common methods: flameproof enclosure (contains explosion within the housing), intrinsic safety (energy limited to non-igniting levels).

Dust environments: Combustible dust suspended or deposited in air creates explosion conditions. Dust protection not only prevents ignition sources but also prevents dust entering equipment (enclosure sealing grade, lower surface temperature control — dust layers reduce heat dissipation and raise surface temperature).

Mixed environments: Some processes have both combustible gas and dust (chemical, pharmaceutical) — equipment must meet both protection requirements.

Key reminder: An AMR certified for gas Zone 1 cannot be used directly in dust Zone 21. If your route passes through dust zones, confirm the equipment has dust zone certification.

Ignition Risks from Batteries, Motors, Sensors, and Connectors

In explosion-proof AMRs, every electrical and mechanical component can be an ignition source. Certification must cover the complete system, not just the main controller.

Important judgment: If any component is not within the explosion-proof certification scope, the entire AMR has an ignition risk at that component. Every component on the certified list must match the actually delivered equipment — replacing any component may invalidate the certification.

Protection Methods: Flameproof, Intrinsic Safety, and Others

Protection methods determine how the equipment prevents ignition sources from igniting surrounding combustible substances. Different methods have different engineering principles, limitations, and applicable scenarios.

Protection method definitions, applicability, and engineering requirements are specified in the relevant IEC 60079 series standards — this table is a summary. Refer to certification documents for the specific protection method of each component.

An explosion-proof AMR may use multiple protection methods simultaneously — flameproof motors, intrinsic safety sensors, encapsulated communication circuits. Request a complete explosion-proof equipment list (including each component’s protection method, certification number, and applicable zone).

What Part of the AMR System Does Certification Cover

Certification scope is the most commonly misjudged aspect in procurement.

Whole-machine certification: The entire AMR is certified as a system, with all components on the certified list. This is ideal — but in practice, many “explosion-proof AMRs” have only partial component certification.

Component certification: Motors, controllers, and other key components are individually certified, but the whole system lacks overall certification. In this case, the connection methods, wiring paths, and installation conditions between components must strictly follow certification conditions — otherwise the overall certification is invalid.

Boundary issues:

• Is the charging station within certification scope? Charging stations are typically installed in non-hazardous areas, but if the route passes through hazardous areas, the charging station location must be clear.
• Is the top module within certification scope? Adding a non-certified lift or roller module may void the explosion-proof rating.
• Is certification still valid after maintenance and component replacement? Replacing tires, sensors, batteries must use equivalent models from the certified list.

Request the complete Ex component list, confirming each component’s certification number, protection method, and applicable zone. Confirm the rules for any component replacement — whether equivalent alternatives are allowed or only specified models from the certified list.

Maintenance, Charging, and Service Area Boundaries

The permitted charging, maintenance, opening, connection, and component-replacement conditions must follow the delivered equipment’s certificate/marking, conditions of use, OEM instructions, site hazardous-area rules, and applicable workplace requirements. A non-hazardous service area is a common design choice, not a universal rule.

What to confirm during procurement:

• Which maintenance operations require a non-hazardous area? (Cover opening, battery replacement, electrical connection/disconnection, component replacement.)
• Where is the charging station permitted? Confirm the charging station location and any certification requirements for charging contacts.
• What are the approved failure recovery procedures within a hazardous area? (Towing, manual push, manual release — confirm spark risk and permitted actions.)
• What are the component replacement rules? Confirm whether equivalent alternatives are allowed or only specified models from the certified list.
• What are the conditions for returning to operation after maintenance? (Reset, inspection, recertification if applicable.)

Hazardous Area RFQ Checklist

Use this checklist during inquiry to systematically define explosion-proof AMR requirements.

Hazardous Area Requirements Table

Hazardous Area RFQ Inputs

1. Do area classification first, then select equipment — a process safety engineer determines the hazardous zone levels and combustible substances on the route.
2. Confirm gas group and temperature class cover your environment — not all explosion-proof AMRs suit all combustible substances.
3. Request the complete Ex equipment list — confirm every component is within certification scope, not just the main controller.
4. Confirm whether certification covers the whole machine or partial components — component-certified machines require strict installation per certification conditions.
5. Charging and maintenance conditions must follow the equipment certificate and site rules — confirm the permitted charging location, maintenance area, and component replacement rules upfront.
6. Component replacement rules must be confirmed upfront — replacing tires, sensors, batteries must follow the certified-list rules; any component change may invalidate certification.
7. Any component change may invalidate certification — do not add non-original modules without confirming explosion-proof compatibility.