First developed by NASA in 1964 Mylar emergency blankets or also known as space blankets or thermal blankets are made from a thin sheet of plastic usually PET film that is coated with a metallic reflecting agent. Typically the blankets are gold or silver in color. The material is designed to reflect up to 97 percent of radiated heat. The blankets are designed to be waterproof as well.
The reflective nature makes Mylar blankets literally a lifesaver in cold weather survival situations. A Mylar blanket wrapped around your body will reflect heat back to the body helping to prevent hypothermia.
Besides keeping the body warm and protected from rain and snow there are many other uses for Mylar blankets. Uses you may not have thought of.
In addition to the typical Mylar blanket found in many off the shelf first aid kits there are space blankets that are considered all weather. The blankets are heavy duty and not a “one-time-use” blanket.
You can purchase the blankets that have grommets in all corners so the blanket can be used repeatedly like a tarp to make emergency shelters, cover/protect gear and they can be used as ground cover/insulation in cold or wet conditions.
Having more than one blanket means you can create a bigger shelter by securing the blankets together using the grommets and cordage. Some believe the blankets are warmer than wool without the weight. They are waterproof, as well, so there is any number of uses.
The heavier emergency blankets come in bright colors making them ideal for signaling rescue personnel. Red or orange would be ideal for signaling.
1.) Fire Starting
You may have seen the episode of Fat Guys In The Woods (Season 2, Episode 1″Operation Desert Patrol”) where Creek Stewart uses a plastic coffee can, a Bic pen and a small piece of a Mylar blanket to create a parabolic fire starting device.
A parabolic reflector is a concave reflective surface that is used to collect and project energy, in this case, energy from the sun’s rays. The reflective surface Creek used was a piece of a Mylar blanket.
The container was a plastic coffee can with its lid. The lid center was cut out leaving enough of the lid to secure a piece of the Mylar over the top of the can leaving an ample reflective surface showing. A hole was cut close to the bottom of the can and a Bic pen was inserted. The empty pen case acted as a straw.
To create a concave reflector one of the guys had to suck the air from the can drawing the Mylar piece into a concave shape. The shape is the same as the reflector behind your headlight bulbs.
The straw would have to be stout enough material so it would not collapse as you sucked on it. The plastic straws you would typically have at home would likely collapse before all of the air was drawn from the can.
The problem with the device the guys made is that it required two people, one to hold the vacuum by sucking in to keep the shape of the material, and another one to hold dry tinder so it catches the concentrated rays. This device does work however and other variations of this device can be made and used effectively if you are alone.
What you can do if you are alone is to fashion a piece of Mylar over a plastic or even a metal container or use a depression in the ground. Place a small amount of tinder on a piece of bark or metal so the ember can be moved to your tinder pile. The tinder will act as a weight to create the concave shape. Using metal or bark will also keep the ember from burning through the Mylar.
The reason Creek used the can is so the concave shaped could direct and better concentrate the sun’s rays onto the tinder instead of the tinder being heated while in the center of the concave shape. This method would work better, but as you can tell it requires two people.
The shape is what concentrates the sun’s rays onto the tinder, similar to how a magnifying glass would concentrate the rays enough to create heat that would ignite combustible material. Set in direct sun and wait, it requires patience, and you may have to move the device around some.
Use any type of bowl or depression to create the same effects, by lining the depression with the Mylar’s’ reflective side out.
2.) Cooking/Water Purification
Again use a bowl or even a depression in the ground lined with Mylar to create a solar oven. Place food in the center and let the heat do the rest. You can also purify water using this method as well. You would need a clear, safe for water container, such as a water bottle or plastic jug. Place the container full of the contaminated water in the center of the depression.
Three things will begin to happen. First, the debris in the water will start to settle, which in and of itself, helps to purify the water, and secondly the heat created is essentially pasteurizing the water and three UV rays are helping to kill bacteria in the water.
If using UV rays alone it will take about six hours to kill the bacteria and parasites. However, by concentrating the rays you are creating heat, which helps to speed up the process. Water can be pasteurized at temperatures well below boiling.
Giardia, Cryptosporidium, Salmonella typhi, and E. coli for example are killed at 140° F (60°) while Hepatitis A is killed at 149° F (65° C). Contaminates will be destroyed if the temperature is maintained for a specified period. You are not likely going to have a way of measuring the heat produced so leave the water in place as long as possible.
3.) Signaling Device
To create a mirror for signaling you could cut a square of the material or use the entire blanket by securing to the ground in a clear area. If you see an aircraft for example, you can fan the material about to reflect the sun’s rays. To make it easier to hold and carry and to maintain its shape wrap the material around and secure to a piece of cardboard, wood or plastic. Use as you would any signaling mirror.
The material can be cut into strips and braided or used without braiding if the job does not require stout cordage. To use as fishing line you would cut three strips and braid together to create a heavy line. The material rips and punctures easily, but it does have a decent tensile strength when used as cordage.
5.) Reflect Sunlight Off Your Body
Not only will Mylar blankets reflect body heat back to the body it can also reflect sunlight away from the body. Use the blankets to escape the blistering rays of the sun, so use like a tarp to create a shaded area. Do not wrap yourself in the blanket however, in hot weather.
6.) Fishing Lures
You can wrap pieces of the shiny material around an object that can be attached to your fishing line to act as a lure. You can also cut into strips and tie the strips to a weighted line to act as bait or lures.
7.) Use to Collect Dew or Rain Water
Drape over vegetation and then create depressions in the material to collect dew overnight. You can secure the blankets in many ways to create a depression to collect rainwater. Dig a small hole and line with the material, for example, but make sure the area around the hole is not obviously contaminated with animal feces, other contaminates or poisonous vegetation, because of ground runoff filling the depression.
8.) Use To Direct Your Campfire Heat Into Your Shelter Or On To Your Body
Hang or drape the blankets so the heat from your fire is directed to where you want it. Ideally you would have more than one blanket so you could line your shelter walls to keep the heat contained while other blankets can direct heat into the shelter.
9.) Dry Your Clothes Quickly
Even if the air is cold Mylar will quickly dry clothes placed on the material in direct or even indirect sunlight. Wet clothing is deadly in cold weather, so as soon as possible get out of the wet clothes, and then wrap yourself in a blanket then lay another blanket out in the sun and place the clothes on it. Wring the clothing out as much as possible before placing on the blanket. Do not overlap the clothing, and turn occasionally for faster results.
10.) Use As A Shelter
While it is obvious that they can be used as an emergency shelter it is worth mentioning it again. In a survival situation people may forget there is probably a blanket or even more than one in their first aid kit that can be used like a tarp or poncho to keep the rain and snow off you and your gear.
Other Uses Include
- Keep the hot sun from heating up the rooms in your home by covering glass panes with Mylar blankets.
- Hang in doorways to close off rooms in the winter. The blankets will keep heat from escaping the rooms you are occupying.
- Hang a blanket behind a wood stove, radiator, or other heating device to reflect the heat into the room.
- Cut into strips and use for securing splints or make a sling to immobilize a broken arm.
With a little imagination you can come up with even more uses for Mylar emergency blankets whether in a survival situation, around the home or at your campsite.