How Far Away Should You Be From Your Red Light Panel? A History Lesson.
How far away should I be from my red light therapy panel?
This blog we dive into one of the most common questions around the red light panel industry, how far away should you be from your light panel?!
Most companies talk about being 6 inches away from their panel. But more recently some companies say 4 inches, others use narrow beam angles and might say 12 inches.
When Dr. Hamblin was asked "How close do you want to stand or be near one of these devices?" His answer would surprise most people who have been brainwashed by the current red light panel brands and marketing.
Dr. Hamblin answered:
"It doesn't have to be on the skin, I put it on my skin because I think its more efficient. The LEDs touching your skin, more of the light goes in rather than being diffusely reflected."
"The led light is not focused, so if you stand in front of a LED panel, a surprising amount of the light is diffusely reflected off your skin, if you lie ON the LED panel, much more of it goes in."
Listen to the interview yourself! Start at the 28:26 time point for this question.
And why does Dr. Hamblin in a more recent interview laugh at the mere concept of standing in front of a light panel? Isn't he an advisor for Joovv, where Joovv is now advising people to be even FURTHER away from their version 3.0 panels, despite the clear perspective from thier own science advisor.
Something doesn't add up. So we are going to dig into the history a bit to help you clarify the truth and root cause of this conflicting information.
Of course you should always defer to your original brand or company that sold you the panel for their usage guidelines. There may be important design or safety reasons for their recommendations. So always check with them first.
In this blog we will go over some general tips and concepts to help you determine how far away you should be from your red light panel. But first, you need to understand WHY we even talk about being a certain distance away.
Lets get started!
Why is distance important with Red Light Panels?
There are 3 major reasons why distance is important with red light therapy panels, and some of them will surprise you because the truth has been well hidden by companies.
- To avoid non-natural EMFs being emitted by the panel.
- The magnetic field for most of your typical full-body panels at 0 inches ranges from 6 milliGauss to 60+ milliGauss! Many health-influencers would not recommend exposure to such high magnetic fields.
- As a form of marketing to the alternative health community, the clever marketing scheme was formulated to claim "no EMF at treatment distance." This way to lure in all the major health influencers because most of them have an anti-EMF stance as well.
- So, for EMF safety reasons, you usually want to be at least 4+ inches away from most panels to avoid the excessive EMF exposure.
- Read more about EMFs from panels in our other blog!
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Read about the potential dangers (and benefits) of EMFs in this blog!
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To claim the magical “100mW/cm^2” intensity.
- The “original” Joovv marketing campaign was that their Elite panels emitted 100mW/cm^2 at 6 inches away measured by a solar power meter, and implied that any intensity less than that would be ineffective (completely unsubstantiated claims).
- Of course we now know that solar power meters are improper to measure intensity, and that Joovv has never delivered 100mW/cm^2 at 6 inches away. They switched their marketing to say something misleading like "100mW/cm^2 at device surface" - while still recommending being 6 inches away.
- Regardless, most companies are still lying about intensity and using solar power meters to claim “>100mW/cm^2 at 6 inches away” despite us debunking that lie multiple times now.
- This would imply that being closer than 4 or 6 inches away means excessively high intensity exposure.
- Too much intensity (being too close) can lead to overheating of tissue.
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Light intensity decreases with distance.
- Per the inverse square law, we know that light will diffuse away and reduce intensity with distance.
- Older generation red light panels used wider beam angles like 90 degrees. Meaning it was even more important to be as close as possible to the panel so the intensity isn’t lost.
- Newer panels with 30 degree beam angles (or less) could be fine being further away.
- Learn more about this concept in our Beam Angle Blog Post!
So basically the goal is to be as close as possible to the red light panel to get a reasonable amount of intensity and minimize beam angle losses, but be far enough away to avoid unnecessary EMF exposure or overheating the tissue.
Note we haven’t mentioned anything about the clinically-studied effectiveness at 6 inches away yet.
Nearly all of these reasons for being 6 inches away are based on design flaws (EMF and wide beam angles), and marketing with incorrect intensity measurements. Nothing "clinically based" about it.
Why is being 6 inches away is NOT supported by the science?
You might think that 6 inches is some magical clinically-studied treatment number since that is what everyone talks about. But you would be surprised that there are practically NO studies referencing 6 inches.
Most studies prefer to use skin-contact with the Laser or LED device, since they know that will minimize skin reflection losses. Check out our earlier blog for more details.
You can see in most photographs of people with red light therapy that there is a significant amount of light reflecting off of the skin!
So standing any significant distance away from a red light panel will result massive losses due to skin reflection alone!
The NIST database of skin reflectance spectrum measurements shows a skin reflectance on average of about 60% in white skin around 660nm to 850nm! This is very high!
Proper analysis of the raw NIST data shows from 660nm to 850nm the average reflection of human skin is about 60%!
Other references which corroborate the high average reflection estimate of 60% include:
1. The evolution of human skin color measured reflectance at 685nm in Northern Latitudes at about 65%! [2]
2. Another reflectance measurements of human skin study showed a very similar spectrum as the NIST data. [3]
3. Researchers used a camera technique to measure reflection spectrum and found about 60% reflection (and increasing) in the Red range. [4]
4. Spectral Reflection study of facial skin of 241 participants showed an average reflectance of 60% in the red range and clearly increasing reflectance towards NIR. [5]
5. In one review the authors mention how 4-7% of most wavelengths pass through the first layer of skin, but through internal reflection and scattering, light will exit the body through what is called remittance. Their remittance spectrum shows similar to the NIST data, with Caucasion skin having over 60% remittance between 600nm to 900nm. [6]
6. One study notes the reflection is: "with maxima for lightly pigmented (fair) skin in the visible and in the IR-A range of up to about 60–70%" - confirming the high skin reflection in the same range. [8]
So ALL 6 of these references match very well, no matter what year they were studied, including the NIST data makes 6 well studied skin reflection metrics.
60% reflection is a tremendous amount of intensity losses! Lets say you have a panel that you THINK emits 100mW/cm^2 at 6 inches. Well actually they lied about intensity and it is about 45mW/cm^2 at 6 inches. Then 60% of that gets reflected away so you are left with an effective intensity of 18 mW/cm^2. Is that what you paid for?
Most panel companies don’t tell you about skin reflection because they don't want their customers to realize they are using an inefficient and mostly unscientific dosing method by being 6+ inches away. And some delusional brands and self-proclaimed experts may not even be aware of this issue.
Clinical Study Example:
In the first-ever study using a Joovv Elite system had athletes use the panels at 12 inches away for 5 minutes. Based on their calculations with skin contact dosage in earlier studies, the authors thought 5 minutes would be plenty sufficient for a clinical benefit. But they found no significant improvement in the treatment group. [7]
This is what happens when companies don’t educate the market about the skin reflection issue. It hurts the science and customers might not get the results that they expect then they stand 6+ inches away from a panel.
Skin contact with a torch shows the light penetrating and diffusing through the skin much more than with non-contact treatment.
This is why even some low-EMF LED panels, flexible LED pads, and flashlights/torches can be very effective with skin-contact, even though their overall power or intensity is much lower than a panel.
Deep treatment VS Skin Treatment
Let say you have a red light panel with high EMF at 0 inches, and are trying to figure out your optimal treatment distance.
Basically, you can use your “distance” as a way to control the intensity that you are being exposed to.
- If you move further away from the panel, the exposure intensity decreases.
- If you move closer, the exposure intensity increases.
Now hopefully you bought a panel with accurate 3rd party testing at multiple distances from the panel. If they just used a solar power meter, you will never be able to dose it properly.
For sensitive treatment areas like the skin, face, and genitals – a lower intensity treatment may be more suitable. Those areas will respond quickly to treatment and you don’t want to risk an overdose. So this means being further away from the panel in the range the intensity is 5 to 20 mW/cm^2. But again, don’t use a solar power meter for this measurement otherwise you will be way too far away.
For deeper treatment into the muscles, bones, or systemic benefits then going for a higher intensity treatment could be in the range of 25-35 mW/cm^2.
*note, these intensity ranges are from anecdotal experience since there isn't much data for non-contact panel dosing*
We probably don’t want to go much higher than exposure of 35 mW/cm^2 since that would lead to too much heating overall. Some people might experience redness of skin, “sunburn” type feeling, exacerbate melasma or pigmentation issues, or lack of skin benefits.
Many consumers unfairly blame the Near-Infrared (NIR) wavelength for causing the heat from the panel. Which is hardly the case because NIR in the 800nm range barely has any water absorption. So the “heat” being experienced is mostly from the total intensity or power being emitted.
So for customers that experience problems with too much heat or exacerbating a skin condition, it would be good to experiment with increasing the distance, or shutting off the NIR. But then why do people buy these big overpowered panels if they have to shut off half the LEDs just to use it?
Conclusion
The common question of “how far away should I be from my red light panel” is very new to the LLLT/Photobiomodulation industry. There are hardly any studies that support being 6 inches away from any light therapy source, since most studies use skin contact.
As far as the clinical studies go. This isn’t even a question. They almost always use skin contact. It is done by default and often isn't even mentioned in the study. Check again our blog about proper dosing with skin contact!
Companies used this gimmick of “6 inches away” recommendation for marketing purposes to claim they are “no EMF at treatment distance”. It was never about clinical studies or real science.
And they claimed that 100mW/cm^2 at 6 inches was some special intensity for effectiveness, which would be unsafe for the eyes and skin if actually exposed to such a high intensity.
Of course, we know that 100mW/cm^2 at 6 inches is also a farce, and most companies are emitting less than half of what they claim when measured by a solar power meter.
So what is the final answer for the proper distance to be from a red light panel? We don’t know for sure, and neither does anyone else until there are more studies with non-contact red light panels..
But here are the general guidelines that we know so far:
- Far enough away to be outside the Magnetic Field (usually 6+ inches away).
- As close as possible to minimize beam angle losses and skin reflection losses.
- Move further away if you feel significant heat or warmth on your skin until it is just a subtle warmth.
- Move further away for skin treatment and sensitive areas, and closer for deeper treatment.
That’s all we can say for now until we get more data!
Finally, you need accurate intensity measurements from your panel to use it safely and effectively.
Thank you for reading!
1. NIST Skin Reflection Data
https://www.nist.gov/programs-projects/reflectance-measurements-human-skin
Raw Data:
https://opendata.nist.gov/
2. Evolution of Human Skin Coloration.
Nina G. Jablonski and George Chaplin
Department of Anthropology, California Academy of Sciences, Golden Gate Park,
San Francisco, CA
https://anth.la.psu.edu/research/research-labs/jablonski-lab/research/JablonskiLabskin.pdf
3.
Cooksey, Catherine & Allen, David. (2013). Reflectance measurements of human skin from the ultraviolet to the shortwave infrared (250 nm to 2500 nm). Proceedings of SPIE - The International Society for Optical Engineering. 8734. 87340N. 10.1117/12.2015821.
https://www.researchgate.net/publication/269325503_Reflectance_measurements_of_human_skin_from_the_ultraviolet_to_the_shortwave_infrared_250_nm_to_2500_nm
4.
Validation of a Method to Estimate Skin Spectral Reflectance Using a Digital Camera.
Christopher Thorstenson
Rochester Institute of Technology
RIT Scholar Works
5-9-2017
https://scholarworks.rit.edu/cgi/viewcontent.cgi?article=10602&context=theses
5.
Koran A, Powers JM, Raptis CN, Yu R. Reflection spectrophotometry of facial skin. J Dent Res. 1981 Jun;60(6):979-82. doi: 10.1177/00220345810600061301. PMID: 6939721.
https://pubmed.ncbi.nlm.nih.gov/6939721/
https://deepblue.lib.umich.edu/bitstream/handle/2027.42/67548/10.1177_00220345810600061301.pdf
[6]
Anderson RR, Parrish JA. The optics of human skin. J Invest Dermatol. 1981 Jul;77(1):13-9. doi: 10.1111/1523-1747.ep12479191. PMID: 7252245.
[7]
Zagatto, Alessandro & Dutra, Yago & Lira, Fabio & Antunes, Barbara & Bombini Faustini, Júlia & Malta, Elvis & Fialho Lopes, Vithor & de Poli, Rodrigo & Brisola, Gabriel & dos Santos, Giovanny Viegas & Rodrigues, Fabio & Ferraresi, Cleber. (2020). Full Body Photobiomodulation Therapy to Induce Faster Muscle Recovery in Water Polo Athletes: Preliminary Results. Photobiomodulation Photomedicine and Laser Surgery. 38. -. 10.1089/photob.2020.4803.
[8]