IR Heating: Questions Answered

Calorific rays were discovered in 1800 by William Herschel when he used a prism to refract sunlight. Using a thermometer, he noticed an increase in temperature beyond the red segment of the visible spectrum. The wavelength of visible light lies in the range between 0.38 (violet) and 0.78 (red) microns, with infrared being ‘just beyond red’ and found between 0.78 – 1000 microns (μm). Over time, these calorific rays became known as ‘infrared’.

Infrared is best thought of as waves moving through space that has different frequencies. From low frequencies, which make up radio waves, to high frequencies such as gamma or X-rays, with the visible spectrum of light our eyes can detect (from violet through to red), somewhere in the middle.

In scientific terms, infrared heat is a form of electromagnetic radiation that transfers thermal energy directly to objects, surfaces, and materials rather than heating the surrounding air. This method of heat transfer, known as radiant heating, delivers fast, efficient, and targeted heat.

Infrared radiation lies on the electromagnetic spectrum between visible light and microwaves. For industrial heating applications, infrared wavelengths typically range from 0.78 to 1,000 μm. Different wavelength ranges are selected based on the material being heated, the required heating speed, and the specific process or application.

An infrared heating element, or emitter, is a component that converts electrical energy into infrared radiation, delivering heat directly to materials rather than warming the surrounding air. When electricity passes through the element, an internal resistance coil heats up. This heat is then transferred to the outer material—typically ceramic or quartz—which emits infrared radiation. The radiant energy travels directly to the target surface, providing fast, consistent heating with minimal energy lost to the surrounding air.

Infrared radiation is typically divided into three wavelength ranges. The exact boundaries and naming can vary depending on the source, but at Ceramicx the following standard is used:

• Short-wave infrared (SWIR): 0.78–1.40 μm, also known as near infrared (NIR) or IR-A

• Medium-wave infrared (MWIR): 1.4–3.0 μm, also known as mid infrared (MIR) or IR-B

• Long-wave infrared (LWIR): 3–1000 μm, also known as far infrared (FIR) or IR-C

This classification helps distinguish different parts of the infrared spectrum based on wavelength.

No, infrared heat is not inherently dangerous. In fact, all objects—including the human body—naturally emit infrared radiation as long as they are above absolute zero (-273.15°C). While infrared can create enough energy to start molecules moving, unlike higher frequency radiation – such as x-rays – it doesn’t have enough energy to break molecules apart or cause damage. Infrared heat will naturally warm up whatever part of you it touches. But lengthy exposure to a high level of IR could be potentially harmful and result in a burn, in the same way as from any other heat source, such as a fire.

Infrared is a form of radiation found just below visible light on the electromagnetic spectrum. When we absorb infrared, the only effect is that we feel warmer. However, IR can be hazardous with prolonged exposure.

The standard supply voltage for ceramic and quartz infrared emitters is 230V. Other voltage ratings are available on request. We can design the heating element to operate at different power outputs and with different voltage ratings at additional cost and are subject to minimum order quantities.

Quartz heating elements should always be mounted horizontally to maintain the structural integrity of the heating coil and quartz glass tube. Horizontal installation helps prevent stress on the internal coil and reduces risk of deformation at high operating temperatures, ensuring reliable performance and a longer service life.

Infrared emitters are frequently used under partial vacuum. The direct transfer of radiant energy is generally more efficient due to the absence of water vapour molecules which would normally absorb some of the infrared radiation.

The optimum distance between an infrared emitter and the target material depends on the application, the emitter type, element spacing, and the required temperature uniformity across the surface. For static applications where both the heater and target are fixed in position, a typical recommended distance is 100–200mm.

In general, the greater the distance, the greater the radiant dispersion, which in turn facilitates uniform heating. However, positioning the emitter too far away may reduce heating efficiency due to greater energy dispersion.

A shorter distance can increase the concentration of infrared energy on a smaller area, potentially creating localised high-temperature areas. The ideal mounting distance should therefore be selected based on the required heating profile, material characteristics, and application requirements.

Choosing the best infrared emitter depends on several factors, including the absorption characteristics of the target material, the required heating temperature, and the response time needed for the process.

If the absorption properties of the target material are known, the peak emission wavelength can be used to select the most suitable infrared emitter.

If those characteristics aren’t known, small scale testing with 1 or 2 emitters may be enough to provide a better understanding of what works with the material in question. 

Another key factor is the thermal response time required by the process. Ceramic emitters typically require about 10-12 minutes to reach steady-state temperature. Quartz cassette emitters require about half this time, with tungsten/halogen emitters close to full output within a few seconds.

Ceramic trough and hollow infrared elements are both manufactured using a high-temperature resistance alloy embedded within a specially formulated ceramic body. The main difference between the two designs is their heat distribution characteristics and suitability for different installation distances.

Ceramic trough elements feature a curved, solid ceramic design that produces a concentrated infrared output. The radiant energy spreads over a greater distance, making trough-style elements well suited for applications where the emitter is positioned further away from the target material.

Hollow elements are lightweight with a hollow-cast ceramic body – filled with high-density insulating material. This gives a significant reduction in rear heat loss and increased radiant output from the front of the element, which is better suited to emitters positioned closer to the target material.

Ceramic Infrared Elements: Average operating life of up to 20,000 hours, depending on operating conditions. 

Quartz Infrared Elements: Average operating life of up to 10,000 hours, depending on operating conditions.

To monitor or control heat temperature for infrared heating elements, including ceramic and quartz emitters and heaters, we recommend using a Type K thermocouple. These can be connected to a suitable temperature controller or monitoring system, allowing the heater output to be adjusted to maintain the required temperature. This helps improve process control, energy efficiency, and heating consistency.

The optimum spacing between infrared emitters in a heater array depends on the application, emitter type, and the distance between the heater and target material. We generally recommend a minimum of 5mm between ceramic emitters when arrayed inside a heater field. The same minimum spacing recommendation applies to quartz infrared emitters.

For secure and stable mounting of an infrared heating element, we recommend using a reflector with a slot hole size of 42mm x 15mm and a reflector thickness between 0.75mm and 0.9mm.

These specifications provide the optimum balance between mechanical strength and reliable element support. Increasing the size or thickness beyond these specifications may cause the pillar to weaken or break.

With our global distribution network, Ceramicx is able to ship infrared heating products all over the world. Email [email protected] to find out more.

Yes. Ceramicx designs and builds custom infrared heating systems and bespoke infrared ovens tailored to your exact process, material, and production requirements. Whether you need a heating solution integrated into an existing manufacturing line or a fully standalone system, our engineering team develops a solution that delivers reliable, efficient performance.

We use shortwave, mediumwave, and longwave infrared heating technologies, carefully selecting the optimum wavelength and power output for your specific application. By matching the infrared heating system to your materials and process, we maximize energy efficiency, improve product quality, and deliver consistent heating performance.

From initial design and engineering through to manufacture and system integration, Ceramicx provides custom industrial heating solutions that help manufacturers optimize production, reduce energy consumption, and achieve repeatable process results.

Yes. Ceramicx designs and manufactures custom infrared heating elements and industrial heating components to meet the unique requirements of your application. If your project requires a bespoke infrared element, or specialized heating component, our engineering team will work with you to develop a solution tailored to your specifications.

We have the capabilities and experience to design, prototype, and manufacture custom infrared heating solutions.