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In this advertising video published by Columbia Sportswear, Omni-Heat Reflective is introduced as a technology which reduces body heat loss by reflecting body heat radiation (back to itself) using silvery dots printed on inner surface of jackets or other clothes (similar to a space blanket).

However, I suspect that:

  1. Body thermal radiation is conserved by most other fabrics as well, without those silver dots.
  2. The silver dots work to keep the body warmer mainly because they are not/less breathable, not because they reflect radiation.

Has there been any independent scientific experiment (for example using thermal imaging) to see how effective this technology is compared to non-reflective fabrics?

Ali Shakiba
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  • [Welcome to Skeptics!](http://meta.skeptics.stackexchange.com/questions/1505/welcome-to-new-users) What is the particular claim you are skeptical about. What do you mean by effective? I had a quick listen to the video, and I wasn't sure what the claim was. They avoided saying much. – Oddthinking Nov 15 '15 at 09:15
  • @Oddthinking I have update my question. – Ali Shakiba Nov 15 '15 at 22:01
  • Thanks, @Ali. Note that (with the exception of "electric"), the in the diagram claims would be met by a cotton t-shirt. There is nothing substantive here. (No, they aren't "20% warmer"! Even if they just meant "20% warmer than naked", that would be about 50-60 degrees C more, and likely fatal!) – Oddthinking Nov 16 '15 at 00:32
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    @Oddthinking I assume they mean it reduces body heat lose by 20%. I'm interested to know if the thermal reflective silver dots used in this jacket (which is inspired by "space blanket") is effective here or just a gimmick. – Ali Shakiba Nov 16 '15 at 00:41
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    "it reduces body heat lose by 20%" - Yeah, but any thin jacket probably reduces body heat loss by about 20%. The claims here have been worded by advertisers to carefully avoid making any actual claims beyond "Hey, it is a jacket." I am confident it works as a jacket, so what does it mean to say it isn't effective. – Oddthinking Nov 16 '15 at 01:28
  • @Oddthinking I removed the image, because my main question is about effectiveness of (only) the reflective silver dots in reducing the body heat loss by reflecting body heat radiation. – Ali Shakiba Nov 16 '15 at 02:18
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    @Oddthinking It never really makes sense to refer to a percentage of a temperature, since there's no generally agreed baseline. 0 C, 0 F and 0 K are very different to each other. – bdsl Nov 16 '15 at 10:04
  • @bdsl: We are thinking along the same lines. My comment about 50-60 degrees C was using 0 K as a baseline, which is the only sensible one. – Oddthinking Nov 16 '15 at 10:33
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    If they mention `20% reduced heat loss` then that is not a 'percentage of temperature', but essentially an energy flow and it can be easily measured (https://en.wikipedia.org/wiki/Heat_flux). Although I do admit this is still very vague and depends on a lot of factors. – fgysin Nov 17 '15 at 17:39
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    According to Wikipedia, space blankets work primarily because they are impermeable - thus greatly reducing heat loss by convection and evaporation. Additionally, "to a limited extent the reflective surface inhibits losses caused by thermal radiation". This suggests that the reflective dots are probably not tremendously effective in a jacket which is not impermeable. – Mark Nov 18 '15 at 12:21

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