What is it?
This is a Mylar thermal blanket that is used to reflect heat and keep you warm in the event of an emergency. These blankets are also sometimes referred to as space blankets, first aid blankets, emergency blankets, or simply a thermal blanket. An emergency blanket is made of a low bulk and lightweight material that is easily packable. It is typically a plastic film that has been coated with a metallic agent, usually vaporized aluminum. NASA first developed this material because they needed the smallest and lightest possible insulation to fit inside the spacecraft, which makes them perfect for fitting inside a bug out bag.
A thermal blanket is a must-have for any emergency kit or bag and is great to have with you while camping, hiking, or prepping for an emergency. You can use it to stay warm if you become lost or trapped. You may also come across an injured hiker and need to help keep him or her warm until help arrives. The blanket is small and light and will easily fit into most first aid kits or bail out bags. The best application for these blankets is in emergency situations to help protect against hypothermia. If you are lost and need to be identified by rescuers, the blanket doubles as a signal because it is so reflective. Emergency blankets are also known for their usefulness in do-it-yourself solar projects and can be used around the home.
How does it work?
The reflective Mylar material warms you by reflecting your heat and then trapping it in the air pockets that surround you. It reduces loss of body heat due to convection by providing a barrier between you and the elements. This will stop heat loss due to things such as perspiration, evaporation and moisture. The blankets cannot stop heat loss due to conduction either. This means that you can still lose heat if lying on the ground because there are no air pockets to trap the heat beneath you and the material will not stop your body from transferring heat into the ground.
Here is a summary of the main features of the emergency blanket:
- Waterproof and windproof
- Retains up to 90% of your body heat
- 54 X 84 inches
- Weighs less than 1 lb.
The material is made of a very thin plastic and is therefore extremely flimsy. Although you may be able to get multiple uses out of it, it is typically made for one use only. If you are reusing the blanket, it can be difficult to repackage into a small size. The material will only protect against convection and not conduction, so you will not be insulated from the cold ground if you are lying down.
Do I need this in my bug out bag?
The Emergency Mylar Thermal Blanket keeps in 90% of your body heat and helps to preserve your body temperature. It is small enough to fit in most first aid kits and is lightweight. A set of emergency blankets like this are an absolute must have in any well built bug out bag. The blankets are good to have in case of emergency, natural disaster, or nuclear meltdown, but should not be relied upon as your sole source of warmth if you are packing a 72+ hour bag. These would also be good to have in the home and in the car in case of emergencies during the colder months.