Independent Testing. Results You Can Explore.

The test shows how the tested FireLight® bulb’s light output is distributed across wavelengths. The horizontal axis identifies the wavelengths, while the height of the curve shows the measured output at each wavelength. Its broad, continuous shape reveals the character of incandescent light: output spread across a range of wavelengths, including visible red and near-infrared light. This gives you an independent view of the spectrum behind FireLight®.

Explore the wavelengths that make up the FireLight Spectrum.

The laboratory used a spectroradiometer—an instrument that measures light output across individual wavelengths—positioned 8 inches from the bulb’s luminous center. The bulb operated on a controlled power supply and was allowed to stabilize for 30 minutes before measurement. These conditions give the spectrum a clear reference point, so the result can be understood alongside the instrument, distance, and operating conditions documented in the report.

FireLight® produces a broad, continuous spectrum from a glowing tungsten filament. LEDs used in red-light therapy typically concentrate their output around selected wavelengths, which appear as distinct peaks on a spectrum chart. The FireLight® Spectrum shows light distributed across a continuous range of wavelengths, bringing visible red light, near-infrared light, and radiant warmth together in one source.

Read why we chose incandescent light for FireLight.

In our experience with FireLight®, its broad incandescent spectrum remains consistent throughout the bulb’s working life. That spectrum comes from a heated tungsten filament, which produces a continuous range of wavelengths rather than isolated peaks. Small variations between individual bulbs are normal, while the broad character of the FireLight® Spectrum remains consistent.

Independent testing by SGS measured an average power consumption of 244.23 watts across 100 production bulbs, compared with their nominal 250-watt rating. Individual readings ranged from 237.16 to 252.89 watts under the test conditions. The rating describes the bulb’s nominal electrical consumption; the report shows the actual measurements across the tested group.

SGS connected each of 100 production bulbs to a controlled AC power source set to 120 volts at 60 Hz. After one minute of operation, the laboratory recorded voltage, current, and power consumption using a power meter. Testing a group of bulbs shows both the average consumption and the variation between samples, giving you more context than a reading from a single bulb.

Small differences between individual bulbs are expected in incandescent manufacturing, and the supply voltage also affects how much power a bulb draws. Alongside the 100-bulb test, SGS checked one reference bulb at different voltages: it consumed 215.73 watts at 110 volts and 265.4 watts at 126 volts. That is why the voltage conditions matter when interpreting a wattage measurement or comparing readings taken in different settings.

Electrical wattage tells you how much power a device consumes. It does not, by itself, tell you how much light reaches your body. That depends on the light source, the wavelengths being measured, distance, and how the light is distributed. Our separate irradiance reports measure light arriving at specific locations in front of Glow and Hearth, helping you understand light delivery alongside electrical consumption.

Light energy delivered to a measured area depends on irradiance and exposure time. To calculate joules per square centimeter, multiply irradiance in mW/cm² by the number of seconds, then divide by 1,000.

For example, the independent Glow report records approximately 22.82 mW/cm² at its center-axis measurement point at 12 inches. Maintaining that irradiance for 10 minutes would deliver approximately 13.69 J/cm² within the measured 600–1000 nm wavelength band.

Your exposure varies with distance, position, and time facing the light. These calculations help put the laboratory measurements into context; they describe energy arriving at a particular location rather than a uniform dose across your whole body. Follow your product’s use guide for session length and positioning.

Irradiance measures how much light power reaches a given area. We express it in milliwatts per square centimeter, or mW/cm². While electrical wattage tells you how much power a device consumes, irradiance tells you about the light arriving at a measured location. It is one part of understanding light exposure, alongside the wavelengths delivered, the area covered, and the length of a session.

TÜV SÜD used a spectroradiometer to measure light within the 600–1000 nm wavelength band, covering visible red and part of the near-infrared range. Measurements were taken at points spaced 2 inches apart across a grid in front of each product: 99 points for Glow at 12 inches, 221 points for Hearth Trio at 18 inches, and 289 points for Hearth Quartet at 18 inches. This approach shows how light is distributed across an area, giving you more information than a single reading at the center.

The maps show where measured light delivery is stronger or weaker across the testing grid. Within the 600–1000 nm band, peak irradiance was 27.74 mW/cm² for Glow at 12 inches, 19.13 mW/cm² for Hearth Trio at 18 inches, and 23.66 mW/cm² for Hearth Quartet at 18 inches. Each peak is the highest reading in that product’s map, rather than the reading at every location. Looking at the map alongside the peak helps you understand both intensity and coverage.

Irradiance generally decreases as you move farther from a light source, while the pattern of light across the receiving area also changes. Alongside the grid maps, TÜV SÜD took separate measurements on each product’s central axis at 12, 18, 24, and 30 inches. Those readings show how light delivery changes with distance at that position. A measurement distance describes the test setup; follow your product’s usage instructions when choosing your position during a session.

Start with the conditions behind the number: the measured wavelength band, distance, instrument, and whether the figure represents a peak, center-point reading, or average. A measurement covering a wider wavelength range can include light that another measurement excludes, and a peak does not describe an entire treatment area. Our reports identify the instrument and test conditions, with map values reported for 600–1000 nm, so you can make a more informed comparison.

SGS independently tested the magnetic fields around the operating Glow, Hearth Trio, and Hearth Quartet. The evaluations covered 10 Hz–400 kHz using IEC/EN 62233:2008, a standard for measuring electromagnetic fields from household appliances in relation to human exposure. These tests give you documented measurements of magnetic-field emissions around each tested product.

SGS used a magnetic-field sensor to take readings on all four sides of each product. The measurement tables record the front and left sides at 30 cm, and the rear and right sides at 10 cm. The laboratory also recorded background magnetic-field levels for comparison. Because emissions were low, the reports explain that closer measurements were used to obtain readings above the surrounding background.

All three tested products—Glow, Hearth Trio, and Hearth Quartet—were found compliant with IEC/EN 62233:2008. Their recorded magnetic-field readings were close to the laboratory’s measured background level. This provides independent evidence of low magnetic-field emissions at the tested positions and distances, with the individual readings available in each report.

The measured percentages express magnetic-field readings relative to the reference value used in the evaluation. They are not percentages of the surrounding environmental magnetic field. Across the three products, measured values ranged from 1.20% to 1.42%, while the laboratory’s background reading was 1.19% on the same scale. Seeing those values together helps explain how close the readings were to background under the test conditions. Each report separately records the compliance result.

Magnetic-field testing measures fields around an operating product. Shielding testing measures how much a barrier reduces an external signal passing through it. Our Glow and Hearth reports evaluate magnetic-field emissions under IEC/EN 62233:2008. The separate SilverLining® report evaluates shielding effectiveness using IEEE 299. These tests address different aspects of the design: emissions around the light panels and the reduction of external signals by the shielding.

The test measures how much SilverLining® reduces a radiofrequency signal passing through the enclosure. SGS first measured transmission between antennas without the enclosure in the signal path, then compared it with transmission through SilverLining®. That comparison isolates the shielding effect.

Testing followed the IEEE 299 method across 400 MHz to 18 GHz, with measurements at the front, back, and both sides. Each side was tested with horizontal and vertical antenna orientations to evaluate how signal orientation affects performance.

Attenuation simply means a reduction in signal strength. Shielding effectiveness is expressed in decibels, or dB. Higher numbers mean greater reduction.

For received signal power, 10 dB means a 90% reduction, 20 dB means 99%, and 30 dB means 99.9%. At 30 dB, one-thousandth of the reference signal power remains.

These percentages describe signal power at the measurement point. They do not describe the percentage of frequencies blocked or the amount of energy absorbed by your body.

Yes. The tested range includes the 2.4 GHz band used by Bluetooth and Wi-Fi, the 5 GHz and 6 GHz Wi-Fi bands, and many frequencies used by cellular networks, including low- and mid-band 5G. It also includes UHF broadcast television frequencies.

Coverage depends on frequency. Some services fall outside this test, including AM/FM radio, VHF television, and millimeter-wave cellular bands above 18 GHz. Our band-by-band results show how the measured shielding varies within familiar wireless services.

Wireless signals have different wavelengths and orientations, and they can reach an enclosure from different directions. Shielding performance depends on how those signals interact with the enclosure’s materials and construction.

SGS tested four sides and two antenna orientations to capture some of that variation. The results show lower attenuation at the front at certain frequencies and higher attenuation elsewhere. Presenting that variation gives you a more useful picture than a single percentage.

ilverLining® provides a barrier that can reduce wireless signals traveling from outside the sauna into the space around you. The reduction during your session depends on the frequencies present, where signals originate, and how the enclosure is arranged and closed.

The laboratory results demonstrate shielding performance under the tested conditions; they do not measure a person’s total exposure during a session. A transmitting phone or other wireless device inside the sauna is also inside that barrier. To minimize wireless sources during your session, leave those devices outside.

Independent testing gives you a way to evaluate product performance beyond a manufacturer’s own description. An outside laboratory measures specific characteristics using documented methods and instruments, creating results you can review for yourself.

For SaunaSpace, that means putting measurements behind our descriptions of FireLight® light output, power consumption, magnetic emissions, and SilverLining® shielding performance—and making the original reports available to you.

Our technology brings together incandescent light, radiant heat, and shielding in ways that can be unfamiliar at first. We wanted to make those characteristics easier to understand through independently measured data.

We commissioned testing to document how our products perform under defined conditions, using recognized industry standards where applicable. Sharing the results gives you a clearer basis for understanding our technology and greater confidence in the information behind it.

Different product characteristics require different tests. Measuring a bulb’s spectrum calls for different instruments and procedures than mapping irradiance or evaluating an enclosure’s shielding effectiveness.

The reports identify the methods and, where applicable, the industry standards used for each test. They also document conditions such as measurement distance, frequency range, and equipment setup. Those details help explain what each result means and how it can be compared with other measurements.

The results help explain the physical performance behind the experience: which wavelengths FireLight® emits, how much light reaches different measurement positions, how much electrical power a bulb uses, and how SilverLining reduces incoming wireless signal power.

Each result applies to the product and conditions tested. Your setup, distance, and surroundings can affect what you experience. These are product-performance measurements; health benefits are a separate question explored through scientific research and our customer reports.

Explore the research behind light and sauna use.

New to SaunaSpace? Start with our introduction to the technology.

For a closer look at the light itself, explore the FireLight Spectrum. To understand how the components come together, visit our FireLight Infrared Sauna Overview.

If you have a question about a report or how a measurement relates to your setup, contact our team. We’re happy to help you understand the details.