# Near Infrared vs Far Infrared Sauna: Full Spectrum Guide

Source: https://www.mars-sauna-room.com/guides/full-spectrum-infrared-explained/

Published 2026-09-10, updated 2026-10-20.

Near infrared vs far infrared comes down to wavelength and heat source. Near infrared (NIR, about 0.78-3 µm) comes from hot, glowing lamps or LEDs; far infrared, in sauna language, is the longer-wavelength heat from carbon and ceramic panels that warm you without visible glow. A full spectrum infrared sauna combines both in one cabin, but "full spectrum" is a marketing term, not a standard, so judge it by each emitter's type, wattage and stated wavelength.

## What are the types of infrared?

Infrared is the part of the electromagnetic spectrum just beyond visible red light. It carries a large share of the sun's energy: of roughly 1 kW per square meter of sunlight at sea level, [about 527 W is infrared](https://en.wikipedia.org/wiki/Infrared), compared with 445 W of visible light. The warmth you feel from infrared sunlight, a campfire or a sauna heater is the same kind of energy at different wavelengths.

Two reference schemes divide the infrared wavelengths:

| Scheme | Band | Wavelength range |
|---|---|---|
| ISO 20473 | Near infrared (NIR) | 0.78-3 µm |
| ISO 20473 | Mid infrared (MIR) | 3-50 µm |
| ISO 20473 | Far infrared (FIR) | 50-1000 µm |
| CIE | IR-A | 780-1400 nm |
| CIE | IR-B | 1400-3000 nm |
| CIE | IR-C | 3 µm-1 mm |

Both schemes are summarized in the [Wikipedia infrared article](https://en.wikipedia.org/wiki/Infrared). Research papers use other cut-offs again: a widely cited 2012 review by Vatansever and Hamblin in *Photonics and Lasers in Medicine* defines [far infrared as 3-100 µm](https://dspace.mit.edu/handle/1721.1/109033) and focuses on the 3-12 µm portion. That is why two articles can disagree on what "far infrared" means without either being wrong.

## Near infrared vs far infrared: what is the difference?

The practical difference is how hot the source is and how the heat feels.

- **Near infrared** sources run very hot, often well over 1,000°C at the filament, and glow red, orange or white. Heat feels concentrated and directional, like standing near a heat lamp.
- **Far infrared** (as the sauna industry uses the term) comes from large surfaces at low temperatures, roughly 60-120°C for carbon panels or a few hundred degrees for ceramic. Heat feels even and soft, with little or no glow.

Physics explains why. Any warm surface emits a broad spread of infrared, and its peak shifts with temperature according to [Wien's displacement law](https://en.wikipedia.org/wiki/Wien%27s_displacement_law): peak wavelength (µm) ≈ 2898 / temperature (K). Hotter sources peak at shorter wavelengths.

| Emitter type | Illustrative surface temperature | Approximate peak wavelength | ISO 20473 band | Sauna trade name |
|---|---|---|---|---|
| Halogen / quartz lamp | ~2500 K | ~1.2 µm | Near infrared | Near infrared (NIR) |
| Red glass heater | Varies by design | Mostly near-to-mid | Near / mid | Full spectrum element |
| Ceramic rod or plate | ~400°C (673 K) | ~4.3 µm | Mid infrared | Mid or far infrared |
| Carbon fiber panel | ~100°C (373 K) | ~7.8 µm | Mid infrared | Far infrared |
| Human skin | ~34°C (307 K) | ~9.4 µm | Mid infrared | — |

Surface temperatures vary by design, so treat these as illustrations, not product specs. The takeaway: most "far infrared" sauna heaters peak in what ISO calls mid infrared. People themselves [radiate chiefly around 10 µm](https://en.wikipedia.org/wiki/Infrared). The trade term is fine to use; just avoid claiming lab-grade band compliance you cannot document.

## What is a far infrared sauna?

A far infrared sauna is a cabin heated by carbon fiber or ceramic panels mounted on the walls, under the benches and sometimes at calf height. The emitters warm skin directly while the air typically stays at [110-135°F (43-57°C)](https://health.clevelandclinic.org/infrared-sauna-benefits). Mayo Clinic describes an infrared sauna as one that [heats your body directly without warming the air around you](https://www.mayoclinic.org/healthy-lifestyle/consumer-health/expert-answers/infrared-sauna/faq-20057954).

Carbon panels are large and thin, which spreads heat evenly. Ceramic heaters are smaller and hotter, so they suit corners and foot areas. Low-EMF versions use wiring layouts that reduce magnetic fields at the seat; the [low EMF sauna guide](/guides/low-emf-sauna-heaters/) explains how to read those claims. Browse cabins in [far infrared saunas](/saunas/far-infrared-saunas/).

## What is a NIR sauna?

A NIR sauna uses near infrared sources as its main or added heat. There are two common approaches:

- **Incandescent or halogen heat lamps**, which produce visible light and near infrared together and feel intense at close range.
- **LED arrays** at specific red and near infrared wavelengths. These produce little heat and are closer to red light therapy panels than to heaters.

Near infrared lamps are usually placed at chest or face height, so guarding, distance and user instructions matter. If you are weighing LED panels against heaters, read [red light therapy vs infrared sauna](/guides/red-light-therapy-vs-infrared-sauna/).

## Near vs far infrared sauna: which feels better?

It is a matter of preference. Users who like the even, wraparound warmth of a gentle sauna tend to prefer carbon far infrared. Users who want stronger, faster-felt heat and the warm glow of lamps tend to prefer near infrared or full spectrum. Because near infrared heat is directional, seating position and lamp height matter more than with wall panels.

There is little high-quality research directly comparing near infrared and far infrared saunas for health outcomes, so neither type can claim to be medically superior.

## What do studies say about far infrared therapy?

"Far infrared therapy" and "infrared heat therapy" cover a range of products, from saunas to heating pads and textiles. The 2012 Vatansever and Hamblin review notes that cell and animal studies have linked [FIR in the 3-12 µm range](https://dspace.mit.edu/handle/1721.1/109033) to biological effects, and that FIR-emitting saunas, lamps and textiles are in use. Laboratory findings do not automatically translate to human benefits.

For people, Mayo Clinic says studies show some evidence of benefit from saunas for conditions such as high blood pressure and heart failure, but that [larger, more rigorous studies are needed](https://www.mayoclinic.org/healthy-lifestyle/consumer-health/expert-answers/infrared-sauna/faq-20057954) and some studies used traditional saunas. Cleveland Clinic likewise says more research is needed on infrared specifically. Describe far infrared benefits cautiously: warmth, relaxation and sweating at lower air temperatures are fair; "detox", "cure" or "deep cellular penetration" claims are not.

This article is general information, not medical advice. People who are pregnant, have heart disease, low or high blood pressure or other conditions should talk to a doctor before using a sauna.

## Far infrared vs full spectrum sauna: how do they compare?

| Factor | Carbon far infrared cabin | Full spectrum cabin |
|---|---|---|
| Heater mix | Carbon panels (sometimes ceramic) | Carbon or ceramic plus near infrared or red glass heaters |
| Visible glow | Minimal | Yes, from near infrared elements |
| Feel | Even, gentle, wraparound | Even base heat plus concentrated warmth at the front |
| Build cost | Lower | Higher (more emitters, wiring, controls) |
| Power draw | Lower to moderate | Moderate to higher |
| 120V suitability | Good for 1-2 person cabins | Check total wattage carefully |
| Typical buyer | Value-focused home users | Buyers wanting a premium, feature-rich cabin |

Full spectrum models add connected load, which matters in 120V markets where a dedicated 15 A household circuit supports about 1,440 W of continuous load. Check the [sauna electrical requirements guide](/guides/sauna-electrical-requirements/) before you specify. For a deeper heater comparison, see [carbon vs ceramic vs full spectrum heaters](/guides/infrared-sauna-heaters/).

## How do you verify full spectrum claims?

Ask for documents, not adjectives. A credible supplier can provide:

- A heater layout drawing showing each emitter, its type and wattage
- The stated peak wavelength or spectral curve for each emitter type, and who measured it
- Total connected load and the supply voltage options
- Safety certification covering the complete cabin; IEC 60335-2-53 now [explicitly covers infrared cabins](https://webstore.iec.ch/en/publication/68677)
- EMF measurements at seating positions, if low EMF is claimed
- Guarding and surface temperature data for near infrared lamps
- Replacement part numbers for every emitter

If a supplier quotes a single "full spectrum" wavelength range for the whole cabin with no per-emitter breakdown, ask how it was derived.

## What does Mars Sauna offer in full spectrum and far infrared?

Mars Sauna builds infrared cabins with carbon fiber (including low-EMF), red glass full spectrum and ceramic heaters, in Canadian hemlock and western red cedar. Infrared models list an operating range of 18-65°C (64-149°F), and most cabins are offered in 110-120V or 220-240V builds. OEM and ODM buyers can customize heater layout, size, wood, voltage, control panel, logo and packaging, for example moving near infrared elements to a different height or switching to 220-240V for a higher total wattage. Browse [full spectrum infrared saunas](/saunas/full-spectrum-infrared-saunas/) and [red light therapy saunas](/saunas/red-light-therapy-saunas/).

## Key takeaways

- Near infrared (0.78-3 µm under ISO 20473) comes from hot, glowing sources; sauna "far infrared" comes from low-temperature carbon and ceramic panels.
- Most far infrared sauna heaters peak around 4-10 µm, which ISO classes as mid infrared; the trade term is common but not a standard.
- Wien's law (peak µm ≈ 2898 / K) is a quick way to sense-check wavelength claims.
- Full spectrum combines both; it adds cost and electrical load, and evidence does not show it is healthier.
- Verify per-emitter type, wattage, wavelength data and cabin-level certification before you buy.

Want a heater layout for your market or project? [Contact us](/contact/) with your voltage and target cabin size.

## FAQ
### What is the difference between near infrared and far infrared?
The difference is wavelength. Under ISO 20473, near infrared spans 0.78-3 µm and far infrared 50-1000 µm, with mid infrared between. In saunas, near infrared comes from hot, glowing lamps or LEDs, while far infrared is the trade name for the longer-wavelength heat from carbon and ceramic panels that warm you without visible glow.

### Is near or far infrared better for a sauna?
Neither is better in general. Far infrared carbon panels give even, gentle heat over a large area and are the basis of most infrared saunas. Near infrared sources add concentrated warmth and a visible glow. Evidence comparing the two in saunas is limited, so choose on comfort, budget and power supply rather than health claims.

### What is a far infrared sauna?
A far infrared sauna is a cabin heated by carbon fiber or ceramic emitters that radiate long-wavelength infrared heat. The air typically stays around 110-135°F (43-57°C) while the emitters warm your skin directly. Most heaters sold as far infrared actually peak around 4-10 µm, which ISO 20473 classes as mid infrared.

### What is a NIR sauna?
A NIR sauna uses near infrared sources, such as halogen or incandescent heat lamps or LED arrays, as its main or added heat source. Near infrared lamps glow red or orange and feel more intense at close range. Many products sold as full spectrum combine NIR lamps with far infrared carbon panels in one cabin.

### Far infrared vs full spectrum sauna: which should I buy?
Choose far infrared if you want even, gentle heat at a lower price and power draw. Choose full spectrum if you want the added glow and concentrated warmth of near infrared lamps and accept a higher build cost and connected load. Check total wattage against your circuit, especially on 120V supplies.

### What wavelength is far infrared?
It depends on the scheme. ISO 20473 defines far infrared as 50-1000 µm, while the CIE's IR-C band starts at 3 µm. A widely cited 2012 review by Vatansever and Hamblin uses 3-100 µm. Sauna marketing usually means roughly 4-15 µm, the range where low-temperature heaters and human skin emit most strongly.


## Sources
- [Wikipedia: Infrared (ISO 20473 and CIE divisions)](https://en.wikipedia.org/wiki/Infrared)
- [Wikipedia: Wien's displacement law](https://en.wikipedia.org/wiki/Wien%27s_displacement_law)
- [Vatansever & Hamblin (2012): Far infrared radiation (FIR): its biological effects and medical applications](https://dspace.mit.edu/handle/1721.1/109033)
- [Mayo Clinic: Do infrared saunas have any health benefits?](https://www.mayoclinic.org/healthy-lifestyle/consumer-health/expert-answers/infrared-sauna/faq-20057954)
- [Cleveland Clinic: Infrared Sauna Benefits](https://health.clevelandclinic.org/infrared-sauna-benefits)
- [IEC 60335-2-53: Sauna heating appliances and infrared cabins](https://webstore.iec.ch/en/publication/68677)