Burn from steam: why does it hurt so much?

A steam burn is not accompanied by visible damage to the skin, but the pain is very strong. Why? The fact is that the surface layer of the skin does not prevent the penetration of droplets of steam into the lower layers, which overheat, not having time to give up the accumulated heat.

Steam burns are a special category of thermal injuries that are not accompanied by visible tissue damage, but pain - strong enough - is present.

As is known, the skin is conventionally divided into several layers: the superficial epidermis, which is constantly renewed, further - the dermis containing the mass of immunocytes, and the hypoderma (it is also the subcutaneous fatty tissue).

Researchers representing the Swiss institute Empa explain: the epidermal layer is really obliged to protect the skin from any irritating effect, but it does not prevent the penetration of steam through itself into the dermis. There, the vapor particles condense, release energy, burning a tender dermis. It turns out that there is a burn, and there is no damage to the epidermis.

The scientists put a number of experiments with the use of pig skin: the material was exposed to hot steam, after which, by means of spectroscopic diagnostics, it was examined how steam enters the skin. It was found that, for the first fifteen seconds, the vapor particles appeared in all layers of the skin - because the epidermal layer had passed them through itself.

Only after filling the epidermis with moisture, the pores contracted, and the vapor particles could no longer penetrate the skin. However, at this stage, the burn was already present.

It is interesting, but when the skin was heated with dry hot air, warming occurred more slowly, and the burn did not occur.

The scientists went further and put other experiments. It turned out that the dermis layer could give out heat without problems, but because of the low thermal conductivity of the epidermis, the dermis cooled slowly. This explains the presence of pain.

Specialists advise a special place to take the prevention of this type of injury. People often burn in the kitchen, with more hands, fingers, sometimes face. If the burn has already occurred, for example, from boiling water in a pot or kettle, then you need to help the dermis to remove heat from the inner layers as soon as possible. To do this, dip the affected area in cold water and keep it there longer. Of course, we are talking about household burns 1 or 2 degrees . More serious burns require urgent hospitalization of the victim, usually in a special burn unit or center. Steam burns of 3 and 4 degrees occur primarily in production or in major industrial accidents.

The study is described on the Scientific Reports pages (https://www.nature.com/articles/s41598-018-24647-x).