Lämpöpussit

Lämpöpussit, often translated as hand warmers or heat packs, are devices designed to generate warmth for personal comfort or therapeutic purposes. They are commonly used in cold weather to keep hands, feet, or other body parts warm.

There are several types of lämpöpussit. Disposable versions typically contain iron powder, salt, activated carbon, and vermiculite. When exposed to air, the iron powder oxidizes, releasing heat through a chemical reaction. These are often single-use and are discarded after they cool down. Reusable lämpöpussit usually employ a supersaturated solution of sodium acetate. When a small metal disc inside the pack is bent, it initiates crystallization of the solution, which releases stored heat. These can be reheated by boiling them in water, which reverses the crystallization process and prepares them for reuse. Another type involves electrically powered packs, which use batteries to generate heat, offering adjustable temperature settings.

Lämpöpussit are popular for outdoor activities such as skiing, hiking, or attending sporting events in cold climates. They are also used for pain relief, with the generated heat helping to soothe muscle aches and pains. Their compact size and portability make them a convenient option for on-the-go warmth. Safety precautions are generally advised, especially with disposable types, to avoid burns by placing them inside clothing or gloves rather than directly against bare skin for extended periods.