Which Keeps You Warmer? (Real Thermo Test)

Comments · 1K

• LE

  @leecarlson9713 · 11 months ago (edited)

  I’m not an engineer.  I’m an 81 yo lady.  But I think the reason your back didn’t warm up as much as your front did was because there was no air pocket between your back and the Mylar as the front had.  No space for air to warm up .  It is important there is an air pocket, to get the maximum amount of warmth.

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• CA

  @cambodianexpress8557 · 11 months ago (edited)

  Just finishing up my 16th year in Search & Rescue here in Oregon. We don't generally use either one of these. Instead, we're REQUIRED to have at least two large garbage bags as emergency shelter for ourselves or our subjects. Just insulate the ground with boughs or dry leaves, maybe against a tree, then slip one garbage bag up over your lower body. Next you slip the other bag down over your upper body SO THEY OVERLAP and sit down. Tear a hole just big enough to breath through and you've now trapped dead air around you and are saving tons of convection and some radiant heat = super fast & effective. We tried the Space Blankets and they are really hard to deploy when cold, wet, and in a hurry, (everything you're fighting when you need the things). Here's a personal tip... PARTLY open the open end of each bag and make and apply a tab of white medical tape. This keeps the ends from re-sticking together so cold, numb fingers can deploy them AND helps you find the open end in low light conditions. (Been there, done that). PS... Don't open the bags completely as you'll never get them back small enough to fit in your pocket. A long burning candle in a small tin can is an amazing added bonus. Be safe.

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• DA

  @DazO9874 · 11 months ago

  I was walking in Scotland some years ago there was a sudden unforcasted rain storm there were 3 distinct groups in the same area. One person pulled out a plastic sheet and envied everyone to keep dry. We stood in a circle pulled the sheet over us an all sat down on the edge of the sheet at the same time, it was incredibly warm and comfortable. That person who carried that sheet stopped us all from getting soaked. If I was to go walking I would now carry a plastic sheet. A big thank you to that person.

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• BU

  @Bushidō_Ryūhiro · 11 months ago

  I trained specifically for this when I was still in the U.S. Army --- Mylar isn&apos;t just to keep you warm and dry as many think--<br>I&apos;ve been to both the Cold Weather and Mountain School (Fort Greeley, AK) and Army Desert Warfare / Environmental Survival Courses (Yuma Proving Ground, Arizona)<br><br>Mylar is a hybrid (multi-use) item --<br>To keep you warm / dry (as mentioned) but also for:<br>cool / shielded out of the sun (opposite from above)<br>water collection <br>cooking<br>floatation device <br>waterproofing<br>signal device <br>thermal defeat<br>radio communications / command &amp; signal<br><br><br>Mylar is on the list of any good survivalist / minimalist item--<br>~ Good luck

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• GU

  @gunlover1955 · 10 months ago

  I am 71 and have been camping for over 60 years with that said,🙄 I think everyone should carry these because they are meant to keep you alive not like a 5 star hotel the key is stay alive and not die! I have heard story about someone using these and then complaining they were cold all night the key here is they are alive to tell their story and not dead!

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• KA

  @KandaJE · 11 months ago (edited)

  Probably the warmest night I ever spent in a freezing tent. &nbsp;I duct taped 4 of these (mylar survival) to the inside walls of a small 2 person tent. &nbsp;In the morning, the entire inside of the tent was ice from our breath but we were both toasty warm all night! &nbsp;I always have at least 8 of them in survival bags.<br>I think the biggest danger that most people don&apos;t realize is that these can make you sweat. &nbsp;When you get wet, THEN you freeze! &nbsp;Keep that in mind!

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• RU

  @RueTheDay001 · 3 years ago

  You hit the nail on the head with your analysis. &nbsp;However, in the future, try testing for a longer period of time. &nbsp;What I and others have found is that the bivy keeps you surprisingly warm for about an hour. &nbsp;Then you will be chilly, but ok, for about another hour. &nbsp;Then at that point heat loss from conduction overwhelms heat retention by blocking convection and radiance and you will be freezing cold. &nbsp;It really isn&apos;t an overnight solution (not surprising since the original use case was to keep marathon runners warm after a race and then the military started using a thicker version as a trauma blanket for keeping soldiers warm during medivac). &nbsp;The other issue is that since they don&apos;t breathe you will get wet from perspiration and then have an immediate issue with evaporative cooling once you exit the bivy. &nbsp;A better emergency solution IMO is the sitting bivy using a rain poncho (bringing your arms, legs, and head inside) and then lighting a small candle to create what&apos;s known as a Palmer Furnace.

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• BL

  @bluskytoo · 10 months ago

  Off topic a bit , but a survival mirror is a must. I was in Air Force rescue and on a training exercise we spotted a survivors mirror flash at 20 miles. I was scuba diving once and kept a mirror in my BCD pocket, got separated in a bad current in open water, they couldnt me see from the boat but saw my mirror flash.

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• IT

  @ithacacomments4811 · 10 months ago (edited)

  If you have a power outage...no heat...place a mylar blanket under your matress pad in your bed.<br>Place another sandwiched between two blankets on top of you.<br>All of your body heat will be reflected back at you...all night!<br><br>I have done this many times while winter camping too.<br>Snug as a bug in a rug!!!

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• 1P

  @1pcmedic · 10 months ago

  That&apos;s how you warm up, fighting to get the blanket open!

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• US

  @user-ym5io2ul1o · 10 months ago

  I used to work outdoors in Yellowstone National Park. &nbsp;When it started to rain we took a garbage bag, poked a hole in the bottom for our heads, two holes for arms and it was a mini raincoat that worked very well.

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• TH

  @theroller5673 · 1 year ago

  I wrap my hat in Mylar blankets when the government is explaining things.

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