What is ATEX lighting and when do you need it at high temperatures?

ATEX lighting is lighting that has been specifically certified for use in environments where there is a risk of explosion due to the presence of flammable gases, vapours, mist or dust. You need it as soon as there is a risk of an explosion in a space or zone that can be triggered by a spark or a hot surface. This applies to a wide range of sectors, from petrochemicals and offshore to food processing and recycling.

In this article, we answer the most frequently asked questions about ATEX LED lighting, the relationship with high temperatures, and when you need both.

In which environments is ATEX lighting mandatory?

ATEX lighting is mandatory in any environment where explosive atmospheres can arise due to flammable substances in the air. This includes locations where gases, vapours, liquids or dust clouds are present that can ignite or explode upon contact with a source of ignition. This is not a choice but a legal requirement.

In practice, this involves a wide range of industrial locations:

Refineries and petrochemical plants
Offshore platforms and LNG terminals
Storage spaces for flammable liquids or gases
Paint and coating factories
Sugar mills, sugar factories and other food producers with a risk of fire
Recycling facilities with combustible dust
Water treatment plants with methane production
Mining sites and underground tunnels

The presence of a combustible substance alone is already sufficient reason to assess the environment and, if necessary, to apply explosion-proof lighting. The assessment of whether a zone is ATEX-compliant falls under the responsibility of the employer or operator of the installation.

What do the ATEX categories and zones mean in practice?

ATEX zones indicate how often and for how long an explosive atmosphere is present in a particular location. The classification determines which category of luminaires is required as a minimum. The higher the risk, the stricter the requirements for the lighting.

For gases and vapours there are three zones:

Zone 0: Explosive atmosphere is continuously or continuously present. This is the most dangerous zone, think of the interior of a storage tank containing flammable liquid.
Zone 1: Explosive atmospheres can occasionally occur during normal operation. For example, directly around a pump or valve in a chemical installation.
Zone 2: Explosive atmospheres are not likely to occur during normal operation, but can occur during disruptions or unusual conditions. Think of the wider environment around a process installation.

For dust, similar zones apply (20, 21 and 22), with the same logic: the higher the number, the lower the risk. The category of an ATEX luminaire must correspond to the zone: in Zone 1, category 2 is required as a minimum; in Zone 0, category 1 is required. This has direct consequences for the construction and certification of the luminaire. ATEX luminaires which you are allowed to use.

Why is standard LED lighting dangerous in explosive zones?

Ordinary LED lighting is dangerous in explosive zones because these fixtures are not designed to prevent sparks, arc discharges, or hot surfaces. Even a small electrical spark or a surface temperature that rises too high can be enough to ignite an explosive atmosphere.

Standard industrial LED luminaires are built for performance and durability, but not for explosion protection. The housing is not gas-tight, the electrical components are not explosion-proof, and the maximum surface temperature is not certified for specific gas groups. In an environment with flammable gases or dust, this is a serious safety risk.

ATEX LED lighting differs in several ways from standard lighting: the housing is robust and gas-tight or dust-proofly sealed, the electrical components are designed so that they do not produce sparks, and the maximum surface temperature has been tested and limited per temperature class. In short: ATEX luminaires do not provide better illumination, but are fundamentally safer in the environments for which they are intended.

How does ATEX lighting work in extreme temperatures?

In ATEX lighting in environments with high ambient temperatures, two factors play a role simultaneously: explosion protection and the thermal load of the luminaire itself. Standard ATEX luminaires are generally designed for normal ambient temperatures, but in industrial environments the temperature can fall well outside that range.

The critical point lies in the temperature class of the luminaire. An ATEX luminaire has a maximum surface temperature that must not be exceeded, because otherwise the surrounding atmosphere could ignite. That maximum temperature is expressed in a T class (T1 to T6). The higher the T class, the lower the maximum permitted surface temperature of the luminaire.

In environments with high ambient temperatures, it becomes more difficult for the fixture to dissipate heat, which can lead to a faster increase in surface temperature. An ATEX fixture that meets its T-class under normal conditions may no longer guarantee that at 80 or 100 degrees ambient temperature. Therefore, it is essential that fixtures for ATEX high temperatures They have been specifically tested and certified for those combined conditions.

What is the difference between ATEX zones and high-temperature environments?

ATEX zones and high-temperature environments are two separate classifications that each impose their own requirements on lighting. An ATEX zone describes the risk of an explosive atmosphere. A high-temperature environment describes the thermal load an luminaire is exposed to. The two can overlap, but that need not be the case.

A steel plant generally does not have explosive gas in the air, but the ambient temperature around a blast furnace or rolling mill can rise to above 100 degrees Celsius. You do not need ATEX lighting for that, but rather fixtures that are resistant to extreme heat and infrared radiation. Conversely, a storage tank for flammable liquids can operate at room temperature: there is ATEX requirement, but high-temperature specifications are less relevant.

The situations where both requirements come together are more complex and require specifically engineered solutions. Examples include chemical processes where flammable vapors are released at elevated process temperatures, or offshore installations in warm climates where flammable gases are also present.

When do you need both ATEX and high-temperature lighting?

You need both when a location presents both an explosive risk and a high ambient temperature. This is less rare than it sounds. In practice, there are several industrial environments where this combination occurs and standard solutions fall short.

Typical situations where both requirements come together include refineries in warm climates, chemical plants with exothermic processes, gas-fired combustion plants, and certain offshore applications. In all of these cases, the luminaire must be both explosion-proof and thermally resistant to the environmental conditions.

The challenge lies in the combination of requirements: an ATEX luminaire that is also resistant to high ambient temperatures must be certified in both respects. This requires a specific design where the luminaire’s heat dissipation is adapted to the combined load, without compromising the explosive safety. Therefore, for the zones themselves, you work with a certified Ex manufacturer, and for the parts outside that, it is advisable to work with a specialist in Industrial lighting for extreme conditions who oversees the entire process.

Practical example: Tata Steel IJmuiden

Tata Steel IJmuiden wanted to make the lighting near the production process more sustainable. Near the hot steel, the temperature rises to +120 °C, the steel radiates infrared and the composition of the air is aggressive. The challenge was therefore primarily a material and thermal one. The lighting design and engineering were JEL handled by Barracuda HT and HT, designed the installation and supplied Snapper HT, based on the situation, HT and Orca HT for each location. These HT versions reflect the infrared radiation instead of absorbing it. Near the work environment, 100 lux is achieved, with an uniformity of up to 0.55.

Heat and explosion hazards are separate issues. In a process like this, temperature, radiation and air composition determine the choice of lighting fixture. In addition, where an explosive atmosphere can arise, an ATEX classification is added, which requires a separate, certified solution. By assessing both questions separately, it is prevented from choosing a fixture that meets one point but not the other.

How ATEX lighting and high-temperature applications JEL Products help

JEL Products Has extensive experience with lighting projects in environments where standard solutions do not work. In high-temperature applications, JEL the lighting itself provides illumination; where there is also an explosion hazard, it illuminates JEL the areas outside the ATEX zones and refers them to a certified Ex manufacturer for the zones. The approach is always focused on the specific situation and not on a ready-made product from the catalog.

Specifically, JEL Products provides support in the following areas:

Lighting for the areas outside the ATEX zones, with referral to a certified Ex manufacturer for the zones themselves
Delivery of high-temperature luminaires from the HT line, including the Orca HT and Barracuda HT for ambient temperatures up to +120°C
Lighting design tailored to the operational and safety requirements of the location
Engineering of the total lighting installation, including foundations, masts and cabling
Installation and commissioning by our own certified personnel (ISO9001 and VCA**)
Maintenance and management for continuity in 24/7 operations

Do you have questions about the lighting of a location with ATEX zones, or would you like to know which luminaires are suitable for your specific conditions? Please contact us via the JEL Products Contact Page for a no-obligation consultation with a specialist.

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