How to perform a risk analysis for lighting in high-temperature zones?

Performing a risk analysis for lighting in high-temperature zones involves systematically mapping the thermal load, documenting the environmental conditions, and then assessing whether a luminaire is technically suitable for those specific conditions. This applies to environments such as steel mills, foundries, drying rooms, and other industrial zones where temperatures consistently exceed 60°C. The sections below answer the most frequently asked questions about this process, from risk assessment to engaging a specialist.

What risks do high-temperature zones pose for lighting?

Standard LED fixtures are designed for ambient temperatures of approximately 40°C to 50°C. In high-temperature zones, the ambient temperature rises structurally above this, which has direct consequences on the lifespan, light output, and safety of a fixture. Without the right approach, this leads to rapid component degradation and unexpected failure.

The main risks are:

Thermal overload of the LED driver: The driver is often the most vulnerable part. With sustained heat, the aging of capacitors and other electronic components accelerates sharply.
Light degradation LED chips produce less lumens as the junction temperature rises. This leads to insufficient lighting levels on the work floor, which affects safety and productivity.
Deformation or burning of casing material: Plastic parts in fixtures that are not certified for high temperatures can deform or, in the worst case, ignite.
Infrared radiation: In environments such as steel mills, not only is the air temperature a problem, but also the intense radiant heat from glowing metal or furnaces. This type of heat load requires specifically designed fixtures.
Condensation with varying temperatures: Zones that are alternately hot and cold, such as near cooling systems or outdoor locations, create condensation risks that put the IP class of a luminaire under pressure.

In addition to technical damage, there is also an operational risk: malfunctioning lighting in an active production environment can lead to downtime, unsafe situations, or even incidents. A good risk analysis therefore always begins with understanding what is at stake when the lighting fails.

How do you map the temperature load in a zone?

Before choosing a luminaire, you need to know what temperature conditions you are dealing with. This sounds obvious, but in practice this step is often skipped. The result: a luminaire that meets the specifications on paper but falls short in the actual environment.

Follow these steps to properly document the thermal load:

Measure the ambient temperature at the installation location. Use a data logger that measures over several work days or shifts, including peak moments. A one-time measurement is insufficient.
Determine whether there is radiant heat present. Near ovens, melting pots or glowing material, the radiant heat on the fixture can be significantly higher than the measured air temperature.
Inventory the mounting position. A fixture that hangs directly above a heat source has a different load than a fixture on the side of a hallway. Heat rises, so height and position are crucial.
Map out ventilation and air circulation. Poor ventilation traps heat. Good air circulation can reduce the effective temperature load on a luminaire.
Note temporary temperature spikes. Some processes generate short but intense heat pulses. A fixture must also be able to handle these peaks, not just the average temperature.

With this data, you can form a reliable picture of the actual environmental conditions. This picture forms the basis for all the subsequent steps in the risk analysis.

Which standards and certifications apply to lighting in high-temperature zones?

For lighting in high-temperature zones, two technical specifications are particularly relevant: the IP class and, in specific cases, the ATEX certification. Both indicate whether a luminaire has been tested and found suitable for severe environmental conditions.

Of IP class of a luminaire Indicates the degree of protection of the device against dust and moisture. In high-temperature zones, a high IP rating is important, not only because of heat but also because of the combination with steam, condensation, or industrial dust. An IP65 or higher rating is a minimum in most industrial heat environments.

ATEX certification is mandatory when there is also an explosion hazard in the high-temperature zone, for example due to flammable gases, vapours or dust clouds. This applies in environments such as chemical plants, refineries or certain grinding installations. ATEX lighting has been specifically tested to ensure it does not cause ignition sources in explosive atmospheres.

In addition, the maximum ambient temperature (Ta) specified for a luminaire is a hard technical limit. Manufacturers list this value in the product specifications. If you exceed this limit structurally, in many cases the warranty and safety classification also expire.

How do you assess whether a luminaire is suitable for the measured conditions?

After mapping the environmental conditions, you compare them with the technical specifications of a luminaire. The maximum ambient temperature (Ta) is the starting point here, but it is not the only criterion. A thorough assessment goes beyond just that single number.

When evaluating the following points should be taken into account:

Ta value versus measured peak temperature: The specified Ta must be well above the measured peak temperature, not just slightly below it. A margin of at least 10°C to 20°C is advisable.
Housing material: Aluminum enclosures conduct heat better than plastic and are resistant to higher temperatures. Also check that seals and cable outlets are temperature-resistant.
Driver location and type: Some fixtures for extreme environments separate the driver from the light source, so that the electronics have less exposure to heat. This is an important design feature for high-temperature applications.
Protection against infrared radiation: Standard fixtures are not designed for this application. Specific heat shielding or reflective coatings are necessary in environments with intense radiant heat.
Maintenance intervals: The more difficult the installation location is to reach, the longer the luminaire must be able to function without maintenance. Choose a luminaire whose MTBF (mean time between failures) matches the maintenance plan of the installation.

For High-temperature lighting It is important to always assess specifications in context. An luminaire that scores excellently on Ta but has a vulnerable driver is, in practice, unsuitable for a harsh heat environment.

What are the consequences of choosing the wrong lighting in a high-temperature zone?

Choosing a fixture that is not designed for actual conditions has concrete and sometimes serious consequences. In practice, we see that the problems do not always manifest themselves immediately, but build up gradually until failure becomes inevitable.

Early failure is the most immediate consequence. A luminaire that operates at the edge of its thermal specifications has a significantly shorter lifespan. What would normally last ten years can fail after just two or three years in a hot environment. That means higher replacement costs, more maintenance moments, and unnecessary downtime.

In addition, the light output decreases faster than expected. In critical production environments, this leads to insufficient illumination in the workplace, which directly affects the safety of employees and the quality of work. Examples include inspection tasks, crane operation, or working with hazardous materials: with poor visibility, the risk of errors and incidents increases.

In the worst case, a wrong choice leads to a fire hazard or the release of toxic substances from overheated lamp components. This is not a theoretical risk: plastic housings or cables that are not designed for extreme heat can degrade in ways that endanger the safety of the entire installation.

When do you engage a lighting specialist during a risk analysis?

You should engage an lighting specialist as soon as the environmental conditions fall outside the standard parameters or when a wrong choice leads to immediate safety or operational risks. In high-temperature zones, this is almost always the case.

Specifically, external expertise is valuable in the following situations: when there is a combination of loads such as heat plus corrosion, heat plus explosion hazard, or heat plus extreme vibrations. Each of these combinations requires a specific technical assessment that goes beyond reading a product datasheet.

Even in installations that are difficult to access, such as lighting at high altitudes, above active production lines, or in confined spaces, it is advisable to involve a specialist. The costs of a wrong choice are disproportionately high in those situations, as replacement is complex, expensive, and dangerous.

A good specialist brings not only knowledge of luminaires, but also experience in lighting design, thermal calculations and knowledge of the relevant certification requirements. That makes the difference between a solution that works on paper and a solution that works reliably for years in practice.

Practical example: Rockwool Croatia

At the Rockwool factory in Zajci, Croatia, lighting was sought that is resistant to ambient temperatures above 110 °C and to the infrared radiation that is released during the production process. A second problem arose: in the summer, the outside temperature already reaches 40 °C, which led to the failure of LED drivers, while they should not be allowed to get warmer than 50 °C. The lighting design, engineering and installation of the system were handled by the company, and more than 100 HT luminaires were supplied, resulting in more than 100 lux on the work floor JEL Products.

A risk analysis that only looks at the production area would have missed that second problem. The heat was not only in the process, but also in the climate around the factory, and affected another component: the driver instead of the fixture. Therefore, a risk analysis for a high-temperature zone should include not only the air temperature and the radiant heat at the fixture, but also the locations where drivers and other electronics end up. Many aspects of this project fell outside existing standards and were custom-engineered, which excludes an analysis based solely on a datasheet.

How JEL Products risk analysis helps with lighting in high-temperature zones

JEL Products Supports technical decision-makers in conducting a thorough risk analysis and selecting the appropriate lighting solution for high temperature environments. This is not a standard advisory process, but a technically-based process that aligns with the specific conditions of your installation.

Specifically, JEL Products support is provided in the following areas:

Analysis of the environmental conditions based on your measurement data or an on-site inventory
Selection of luminaires from the DCbright- Orca and DarkLicht- product lines that have been designed and tested for extreme thermal conditions, including the Barracuda high-temperature floodlights with a temperature resistance of up to +120°C
Lighting design and photometric calculations that take into account the specific installation conditions
Advice on IP classification; for ATEX applications, lighting for the parts outside the zones, with referral to a certified Ex manufacturer for the zones themselves
Complete project management from engineering to installation, commissioning and maintenance
ISO9001 and VCA** certified process for quality assurance throughout the entire process

Working in extreme environments requires a partner who understands the risks and has the technical knowledge to manage those risks. Contact us via the JEL Products Contact Page to discuss how a risk analysis looks like for your specific situation.

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How do you perform a risk analysis for lighting in high-temperature zones?