Walk through any oil refinery, chemical plant, or grain processing facility, and you’ll see numerous light fixtures. Most people never give them a second thought.
However, in these environments, where flammable gases, vapors, or dust may be present, explosion-proof lighting is critical. These specialized fixtures are designed not to ignite the surrounding atmosphere, making them essential for safety.
That’s why you’ll often hear about explosion-proof lights, ATEX luminaires when it comes to hazardous areas. But understanding the complex certification markings and zone classifications, as shown in the following picture, can be challenging.
In this blog, we’ll explore what ATEX luminaires are and how to navigate their certifications for safe use in hazardous environments.
What does ATEX stand for?
ATEX stands for "ATmosphères EXplosibles," which translates from French as "explosive atmospheres."
This is the name given to a set of two European Union directives that govern the equipment and safety precautions required in environments where there is a risk of explosion. While rooted in European legislation, the ATEX directives have become a globally recognized benchmark for industrial safety, signifying that a product has been rigorously tested and certified to prevent ignition in hazardous locations.
What are ATEX luminaires?
ATEX luminaires are lighting fixtures designed, manufactured, and certified to prevent ignition in hazardous industrial environments where explosive atmospheres may be present, ranging from flammable gases and vapors to combustible dusts.
These fixtures are engineered to eliminate potential ignition sources by preventing sparks from electrical components, containing any internal explosions, and ensuring that their surface temperature remains below the ignition point of surrounding substances.
They comply with the stringent requirements of the EU ATEX Directive (2014/34/EU) and often also carry IECEx certification, enabling the use in hazardous locations worldwide.
ATEX zones classification
Classification of ATEX zones hinges on two dimensions: type of substance (gas/vapor vs. dust) and frequency of an explosive atmosphere during normal operations.
Zones for gases and vapors are numbered 0–2, while zones for dust are numbered 20–22.
Gas and vapor zones
- Zone 0: Areas represent the highest risk, where explosive atmospheres are present continuously or for long periods, such as inside storage tanks or process vessels.
- Zone 1: Areas that experience explosive atmospheres likely during normal operations, such as near pump seals or loading points.
- Zone 2: Areas where explosive atmospheres occur infrequently and for short durations.
Dust zones
- Zone 20: Akin to zone 0 but for combustible dust, indicating a constant hazard.
- Zone 21: Aligns with Zone 1, marking areas with intermittent dust clouds.
- Zone 22: Matches zone 2, denoting occasional or brief dust presence.
ATEX Zones and Luminaire Categories
In an industrial facility, various areas are classified into zones depending on the likelihood of an explosive atmosphere being present.
In the oil and gas industry, for example, the vapor spaces within tank farms and the interiors of wellheads are classified as Zone 0. Areas such as loading terminals and pump stations are considered Zone 1. Control rooms or other surrounding areas with minimal risk are designated as Zone 2.
Each of these zones requires luminaires and other electrical equipment to meet strict safety standards.
Under the ATEX directive, equipment is classified into categories based on the level of protection it provides. For a gas environment, Category 1 equipment is suitable for Zone 0, offering the highest level of protection and ensuring continued operation even in the presence of gas mixtures. Category 2 equipment is intended for Zone 1, and Category 3 equipment is used in Zone 2.
Please note that higher category equipment can be used in lower risk zones, but lower category equipment CANNOT be used in higher risk zones. Selecting the appropriate equipment category is critical not only for compliance but also for ensuring operational safety and minimizing the risk of explosion in hazardous environments.
Here is a table about ATEX zone classification and required equipment category:
|
Hazard type |
Zone |
Risk level |
Description |
Required equipment protection level |
|
Gases, vapors
|
Zone 0 |
Highest |
An area where an explosive gas atmosphere is present continuously, for long periods, or frequently. |
1G |
|
Zone 1 |
High |
An area where an explosive gas atmosphere is likely to occur occasionally during normal operation |
2G |
|
|
Zone 2 |
Normal |
An area where an explosive atmosphere is not likely to occur during normal operation, but if it does, it will only persist for a short period. |
3G |
|
|
Dusts |
Zone 20 |
Highest |
An area where an explosive atmosphere in the form of a dust cloud is present continuously, for long periods, or frequently. |
1D |
|
Zone 21 |
High |
An area where an explosive atmosphere in the form of a dust cloud is likely to occur occasionally during normal operation. |
2D |
|
|
Zone 22 |
Normal |
An area where an explosive atmosphere in the form of a dust cloud is not likely to occur during normal operation, but if it does, it will persist for a short period. |
3D |
ATEX vs. IECEx
When selecting luminaires for hazardous areas, you may come across both ATEX and IECEx certifications. So, what’s the difference between the two?
ATEX is required for equipment sold within the European Union and IECEx, on the other hand, is an international certification system that facilitates global market access.
ATEX is based on European Norms (EN) and mandates compliance with the ATEX Equipment Directive 2014/34/EU. Products with ATEX certification must also carry the CE marking, indicating conformity with EU safety requirements.
IECEx is based on the IEC 60079 series of international standards and provides a framework for mutual recognition of test results and certifications across participating countries. This system helps manufacturers reduce duplicated testing, lower certification costs, and speed up time-to-market globally.
At AGC, we offer explosion-proof luminaires certified to both ATEX and IECEx standards, helping you access a broader market with confidence. If you need assistance with your hazardous area lighting projects, feel free to contact us.
