ATEX Certification for IoT Sensors: 5 Things Chemical Procurement Teams Need to Know

Digital level monitoring, automated inventory notifications, and continuous visibility into mobile liquid containers promise greater transparency, lower safety stocks, and more efficient supply chains for the chemical industry.

However, as soon as IoT sensors are used on IBCs, tanks, or other containers in potentially explosive environments, technical performance alone is not enough.

Procurement teams therefore need to answer one crucial question:

Is the proposed IoT solution actually suitable and properly ATEX-certified for the intended application?

Choosing the wrong device can have serious consequences, ranging from delayed commissioning and additional inspection costs to compliance issues and safety risks.

At the same time, the topic is complex because procurement, health and safety, production, maintenance, IT, logistics, and management all have different expectations of an IoT solution.

This article explains the key terminology, typical use cases, and five essential points chemical procurement teams should consider when sourcing ATEX-compliant IoT sensors.

What Does ATEX Mean?

The term ATEX comes from the French phrase “ATmosphères EXplosibles.” It refers to European requirements for equipment and workplaces in which potentially explosive atmospheres may occur.

Two directives are particularly relevant:

• The ATEX Product Directive 2014/34/EU primarily applies to manufacturers and suppliers of equipment and protective systems intended for use in potentially explosive atmospheres.
• The ATEX Workplace Directive 1999/92/EC applies to employers and operators. It covers areas such as risk assessments, zone classification, and the safe use of appropriate work equipment.

For purchasing companies, this means that an ATEX-certified sensor does not remove the operator’s own responsibilities. The device certification and the operational risk assessment must match.

What Is an Explosive Atmosphere?

An explosive atmosphere can form when flammable gases, vapors, mists, or dusts mix with air in a certain concentration. If an effective ignition source is present, combustion can spread rapidly.

Even small electronic devices can potentially become ignition sources, for example through:

• electrical sparks,
• electrostatic discharge,
• hot surfaces,
• batteries or energy storage devices,
• defective electronic components.

For this reason, even a compact battery-powered IoT sensor must be appropriately designed, tested, and marked if it is used in a hazardous area.

Where Are ATEX-Certified IoT Sensors Used?

Typical applications in the chemical industry include:

Level monitoring in IBCs and tanks
Sensors measure the level of raw materials, auxiliary materials, or finished products continuously or at defined intervals.

Automated replenishment planning
Current inventory data can trigger purchasing processes or alert suppliers before a container runs empty.

Monitoring mobile containers
For mobile IBCs and reusable packaging, location, level, and movement data can be combined.

Preventing unplanned production downtime
Consumption data helps ensure that critical materials are available before shortages interrupt operations.

Inventory and container management
Companies gain visibility into where containers are located and how much product they contain.

The commercial value of these applications can only be realized when the sensor is technically and legally suitable for the actual operating environment.

1. The ATEX Zone Must Be Known Before Selecting the Sensor

One of the most common mistakes in procurement is selecting a sensor first and checking its suitability for the hazardous area afterward.

The correct order is the opposite:

First assess the operating area, then select the appropriate equipment category.

For gases, vapors, and mists, hazardous areas are generally divided into the following zones:

• Zone 0: An explosive atmosphere is present continuously, for long periods, or frequently.
• Zone 1: An explosive atmosphere is likely to occur occasionally during normal operation.
• Zone 2: An explosive atmosphere is not likely to occur during normal operation or, if it does occur, will only exist for a short period.

For combustible dusts, the corresponding classifications are Zones 20, 21, and 22.

The Procurement Pain Point

Procurement teams are often given a requirement such as “the sensor must be ATEX-compatible.” This statement is too vague.

A device approved for Zone 2 is not automatically suitable for Zone 1 or Zone 0.

Before issuing a request for quotation, procurement should have access to at least the following information:

• intended installation location,
• applicable ATEX zone,
• gas, vapor, mist, or dust atmosphere,
• relevant substance or gas group,
• required temperature class,
• environmental conditions,
• type and duration of use.

The zone classification should be based on the company’s risk assessment or explosion protection document. It should not be guessed or defined solely by the sensor supplier.

Relevant Stakeholders

Procurement: needs a clear and comparable specification for supplier selection.

HSE and occupational safety: must verify that the zone classification and equipment approval match.

Production and site management: understand the actual process conditions and possible deviations from normal operation.

Maintenance: needs to know where and under which conditions the device will be installed, inspected, or replaced.

2. “ATEX-Certified” Is Meaningless Without the Full Marking

ATEX is not a simple yes-or-no feature.

The key question is not whether the supplier uses the term “ATEX,” but for which equipment group, category, atmosphere, and protection concept the product is approved.

A complete Ex marking may include information such as:

• equipment group,
• equipment category,
• gas or dust atmosphere,
• type of protection,
• explosion group,
• temperature class,
• equipment protection level,
• special conditions of use.

A marking such as “II 2G,” for example, broadly describes equipment in Group II, intended for non-mining applications, for use in a specific category of gas-hazardous area.

However, the complete marking contains additional details that may be essential for operational approval.

The HSE and Engineering Pain Point

Incomplete product data often leads to lengthy approval processes.

Procurement may see an ATEX symbol in a brochure, while HSE or engineering later discovers that important information is missing or that the approval does not match the intended location.

Before placing an order, request at least the following documents:

• complete ATEX or Ex marking,
• EU Declaration of Conformity,
• ATEX certificate or EU-type examination certificate where required,
• operating and safety instructions,
• information on special conditions of use,
• details of approved batteries, accessories, and installation methods.

Pay particular attention to an “X” at the end of a certificate number. This usually indicates that special conditions for safe use apply.

These conditions may concern:

• installation,
• permissible temperature range,
• protection against electrostatic charging,
• battery replacement,
• mechanical protection.

Procurement Best Practice

Make the complete Ex marking a mandatory field in the supplier selection process.

Instead of asking only “ATEX available: yes or no,” require the supplier to document the exact marking and approved application area.

3. The Entire Application Scenario Matters, Not Just the Sensor

Certification always applies to a specific device configuration and a defined intended use.

Changes to the installation method, power supply, enclosure, or accessories may affect safe operation.

For IoT sensors installed on IBCs and tanks, the following questions should be answered:

• How is the sensor attached to the container?
• Is it permanently or only temporarily located in the hazardous area?
• Does the sensor come into contact with the product?
• May the device be opened during operation?
• How is the battery replaced?
• Which accessories are approved?
• Can the enclosure become electrostatically charged?
• Which ambient and surface temperatures occur?
• Is the sensor used on a mobile container?
• Can the container move between different ATEX zones?

The Maintenance Pain Point

IoT projects are often planned around the ideal operating state. In reality, however, devices also need to be installed, cleaned, maintained, inspected, and occasionally repaired.

A solution that requires the container to be removed from the hazardous area for every battery replacement may create substantial ongoing costs.

The same applies when installation or servicing can only be carried out by specially trained personnel.

Procurement should therefore evaluate the full lifecycle, including:

• installation effort,
• required training,
• maintenance intervals,
• battery life,
• replacement procedures,
• cleanability,
• spare-parts availability,
• documentation requirements.

The Logistics Pain Point

Mobile IBCs create an additional challenge.

A container may be located in one ATEX zone at the filling site, transported through non-hazardous areas, and later placed in a differently classified zone at the customer’s facility.

For scalable container management, companies must determine whether the sensor is suitable for every intended location and use case.

Otherwise, they may need different hardware variants, manual exception processes, or restrictions within the container fleet.

4. Connectivity and Cloud Features Do Not Replace Ex Suitability

IoT projects often focus on data transmission, dashboards, APIs, analytics, and artificial intelligence.

In potentially explosive environments, however, the physical safety of the field device remains the first priority.

Whether a sensor uses cellular connectivity, NB-IoT, LTE-M, LoRaWAN, Bluetooth, or another wireless technology does not determine whether it is suitable for an ATEX environment.

The following characteristics are also not substitutes for proper Ex certification:

• low battery voltage,
• low transmission power,
• sealed enclosure,
• high IP rating,
• CE marking,
• general industrial suitability.

An IP rating, for example, describes protection against the ingress of solid objects and water. It does not automatically confirm explosion protection.

The IT and Procurement Pain Point

IT teams correctly evaluate areas such as cybersecurity, data ownership, interfaces, and network coverage.

Procurement must combine these requirements with the expectations of HSE and engineering.

A suitable industrial IoT solution therefore requires several layers:

1. safe and approved hardware,
2. reliable data transmission,
3. effective device management,
4. secure data processing,
5. usable interfaces and applications.

An ATEX-compliant sensor without reliable connectivity provides little operational value.

A powerful IoT platform with unsuitable field hardware, on the other hand, may not be permitted in the intended location at all.

Both perspectives must be included in the specification from the beginning.

5. The Business Case Must Cover the Entire Lifecycle

ATEX-certified hardware is more demanding to develop, test, and manufacture than conventional electronics.

A simple comparison of sensor purchase prices is therefore not sufficient.

Procurement should evaluate the measurable value of the overall solution.

Potential benefits include:

• fewer manual inventory checks,
• lower safety stock,
• fewer emergency deliveries,
• reduced risk of material shortages,
• improved container utilization,
• shorter turnaround times for reusable packaging,
• fewer lost containers,
• more reliable planning,
• automated ordering and replenishment,
• better data visibility for customers and suppliers.

The Management Pain Point

Pilot projects often generate useful data but fail to scale economically.

Common reasons include:

• labor-intensive individual installations,
• missing interfaces,
• insufficient battery life,
• unclear ownership,
• inconsistent certification,
• poor network coverage,
• high levels of manual data maintenance,
• lack of integration with ERP or planning processes.

A robust business case should therefore not look only at the price per sensor.

The more relevant metric is the total cost per monitored container or measurement point over the planned service life.

This includes:

• hardware and installation,
• connectivity,
• platform and licensing fees,
• integration with existing systems,
• maintenance and replacement,
• training,
• internal process costs,
• decommissioning and disposal.

These costs should be compared with measurable savings and avoided risks.

The Operational Procurement Pain Point

Procurement must align several competing interests:

• HSE prioritizes safety,
• IT requires secure systems and interfaces,
• production needs reliable data,
• logistics wants scalable processes,
• management expects a clear return on investment.

A structured proof of concept should therefore evaluate more than whether the sensor can measure a level.

It should test the entire process:

• Is measurement accuracy sufficient under real operating conditions?
• Does data transmission work at the actual site?
• Is the hardware approved for the relevant ATEX zone?
• How much effort is required for installation and maintenance?
• Are alerts and inventory data processed correctly?
• Can operational decisions be automated?
• Can the solution scale to additional containers and locations?

Checklist: Questions Chemical Procurement Teams Should Ask Suppliers

Before making a purchasing decision, procurement should clarify at least the following points.

Certification and Application Area

• What is the complete ATEX or Ex marking?
• For which zones is the device approved?
• Is the approval valid for gas, dust, or both?
• Which temperature class and explosion group are covered?
• Are there special conditions for safe use?
• Are the relevant declarations and certificates available?

Installation and Operation

• Which installation methods are approved?
• Can the sensor be used on mobile IBCs?
• Which environmental conditions are permitted?
• How are cleaning, maintenance, and battery replacement handled?
• Which components may be replaced by the operator?
• What training is required?

IoT and Integration

• Which communication technology is used?
• How is network coverage verified at the site?
• Which data is collected and at what frequency?
• Are APIs or standard interfaces available?
• How are devices, users, and access rights managed?
• How can alerts and replenishment processes be integrated into existing systems?

Commercial Viability and Scalability

• What are the total costs over the service life?
• What battery life can be expected at the selected measurement interval?
• How quickly can additional containers and locations be connected?
• Which service and replacement processes does the supplier provide?
• Which KPIs will be measured during the pilot project?

Conclusion: ATEX Must Be Part of the Procurement Process, Not the Final Check

ATEX-certified IoT sensors create the foundation for digitally monitoring inventory, consumption, and mobile containers in demanding areas of the chemical industry.

However, it is not enough to look for an ATEX logo in a product brochure.

The certification must match:

• the zone,
• the substance,
• the temperature class,
• the installation method,
• the environmental conditions,
• the complete operating scenario.

Successful projects therefore involve all relevant stakeholders at an early stage:

• Procurement defines commercial and contractual requirements.
• HSE assesses hazardous-area classification and explosion protection.
• Production describes the real use case.
• Maintenance evaluates installation and lifecycle requirements.
• IT reviews connectivity, security, and integration.
• Logistics considers container movements and scalability.
• Management evaluates value, risk, and return on investment.

This is how an isolated sensor project becomes a safe, scalable, and commercially valuable IoT solution.

Monitor Chemical Inventories Safely and Digitally

Would you like to improve visibility into the levels, consumption, and locations of your IBCs and tanks, including in demanding industrial environments?

Packwise supports companies in digitally connecting mobile liquid containers using intelligent sensor technology and a centralized IoT platform.

Together, we assess your application, operational conditions, and integration requirements to develop a scalable solution for your container and inventory processes.

Talk to our IoT experts and discover how you can make your container management safer, more transparent, and more automated.

Disclaimer: This article provides general information only. It does not replace an individual risk assessment, ATEX suitability assessment, or professional explosion-protection consultation.