Mylar emergency blanket

Mylar emergency blanket, also known as a space blanket, made of metallized polyester that reflects up to 90% of body heat.

About this subject

The Mylar emergency blanket is a staple in survival and first aid kits. Made from a thin layer of polyester coated with vaporized aluminum, it reflects thermal radiation emitted by the human body, reducing heat loss through radiation. Originally developed by NASA for space missions, it gained popularity among hikers, military personnel, and rescue teams due to its minimal weight (around 50 grams) and compact size when folded.

Its operating principle is straightforward: the metallized material acts like a mirror for infrared heat. When wrapped around the body, the blanket traps warm air, helping prevent hypothermia in emergencies. Beyond human use, it is also used to shield sensitive equipment from direct sunlight and to insulate tents or improvised shelters.

Despite its usefulness, the blanket has limitations. It is fragile and tears easily, especially in strong winds or contact with sharp objects. It is also non-breathable, leading to sweat buildup and discomfort during prolonged use. Therefore, it is best used as a temporary barrier until help arrives or to supplement other insulating items like sleeping pads.

Notably, in adventure races and long-distance runs, Mylar blankets are often given to athletes after finishing to prevent rapid heat loss. They are mandatory gear in many ultramarathons and trekking events.

Frequently Asked Questions

How do you properly use a Mylar emergency blanket?

Wrap the blanket around your body with the shiny side facing inward (toward your skin) to reflect heat back. Cover your head and neck, as they lose heat quickly. Avoid pulling too tight to prevent tearing.

Can a Mylar blanket be reused?

Yes, with care. It can be folded and stored for future use if it has no tears or punctures. However, its durability is limited, and it is best to keep a fresh one in your emergency kit.

What is the difference between a Mylar blanket and a regular blanket?

A Mylar blanket is extremely lightweight (about 50g) and compact, and it reflects radiant heat. Regular blankets retain heat through conduction and convection but are bulkier. Mylar is windproof and waterproof, but provides little insulation on its own if not in direct contact with the body.