Steam causes more severe burns as compared to boiling water because steam contains more heat (i.e40.6 kJ/molcondensation heat) then boiling water, both at the same temperature 100 oC.From that condensation is momentanouswhen in contact with skin, after being liquidifiedit behaves the same as boiling water: still 100 oC and cooling down is slower than condensation.
Steam burns are more dangerous than water burns because more heat is transferred due to the additional release of latent heat of condensation.
To vaporize a liquid, energy as heat must be transferred to the substance in order to break the intermolecular bonds so that the substance becomes gaseous. In the case of pure substances, the temperature remains constant until the liquid has completely vaporized. The heat added during vaporization therefore does not result in an increase in temperature, since it is used to break the intermolecular bonds (hydrogen bond). The heat to be added for the complete vaporization of a certain amount of liquid is also referred to as heat of vaporization or, more generally, as latent heat.
Water requires a very large amount of heat to vaporize. For example, to vaporize 1 kg of water, a heat energy of 2257 kJ is required. If we compare this amount of heat with the heating of water from 20 °C to 100 °C, only 336 kJ is required. Thus, more than 6 times as much heat is needed for vaporization as was necessary for heating! The transferred heat of vaporization cannot simply have disappeared due to the conservation of energy. Rather, this enormous amount of energy is stored as internal energy in the gas phase.
Water needs a multiple of the amount of heat for vaporization compared to heating up to boiling temperature!
During condensation, i.e. when gaseous water liquefies on a cold object, the previously absorbed latent heat is released again. The emitted heat from the substance is absorbed by the cooler object. The (internal) energy of the water decreases and the intermolecular bonds can form again, resulting in the liquid state. In the case of condensation, one also speaks of heat of condensation, which is also a form of latent heat. The amount of heat of condensation is the same as the heat of vaporization.
The energy absorbed by a substance during vaporization in the form of heat of vaporization (latent heat) is released during condensation in the form of heat of condensation (latent heat)!
This understanding now also explains why steam burns are generally much more painful and dangerous than water burns. If the relatively cool skin comes into contact with water vapor (steam), the water condenses there and heat of condensation is released and transferred to the skin. As already explained, due to the large amount of latent heat involved, there is a huge amount of thermal energy transferred. Thus, in contact with steam, significantly more heat is transferred to our skin than in contact with liquid water, although the temperature is the same in both cases (100 °C).
Steam burns are more dangerous compared to water burns because additional latent heat is transferred in the form of heat of condensation!
Note that the human perception of warm or cold is not based on temperatures, but on heat flows (transferred heat per unit time). Thus, although the temperatures are identical at 100 °C in both cases, condensation results in a much larger heat flow. This greater heat flow not only causes a psychologically warmer perception, but also leads physically to more dangerous burns. More information on the perception of warm and cold can be found in the article Why does metal feel colder than wood.
Medically reviewed by Owen Kramer, M.D. — By Zawn Villines — Updated on December 7, 2020
A boiling water burn usually causes immediate pain. If the boiling water stays on the skin or covers a large area of the body, it can cause lasting damage.
A boiling water burn is sometimes called a scald. It can also result from contact with steam.
More than 1 million people seek emergency treatment for burns each year in the United States, and about 10,000 die from burn-related infections.
The right care for a boiling water burn can ease the pain and reduce the risk of serious complications. Learn more about the causes, symptoms, and treatment options for boiling water burns in this article.
Share on PinterestRunning skin under cold water for at least 10 minutes can help treat burns.
Immediate first aid can reduce the risk of serious complications.
After sustaining a boiling water burn:
- Stop contact with the source of the burn as quickly as possible. If the hot water is on clothing, remove the clothing, unless it is stuck to the skin.
- Cool the skin by running it under cold water for at least 10 minutes.
- Do not put oils or any other products on the burn.
Seek emergency aid if the burn:
- is very painful
- covers a large area of the body
- causes no pain, but the skin looks very damaged
- is severe
In the emergency room, a doctor will assess the burn and determine whether it needs treatment. A person may need antibiotics or intravenous — IV — fluids. Skin grafts can repair the damaged area after a severe burn.
Seek medical attention for burns on the face. Also, see a doctor for a minor burn if a fever, red streaks, draining pus, or other signs of infection occur.
It is safe to treat some minor burns at home. The following home treatment tips can support healing:
- Keep the burn moisturized. Water-based lotions or aloe vera work well. Avoid other home remedies, such as toothpaste, cooking oil, or butter.
- Keep the wound clean. Gently wash the burn daily with mild soap and cool water.
- Do not pick at the burn or pop blisters. This can damage the skin and lead to infection.
- Take over-the-counter pain relievers. Some examples include ibuprofen and acetaminophen.
- Cover the burn with a sterile bandage that does not stick to the injured skin.
Accidents involving boiling water occur frequently. Some common causes of boiling water burns include:
- spilling boiling water while pouring coffee or tea
- forgetting that a kettle or pot contains boiling water
- playing near stoves or hot water
Sometimes boiling water burns are deliberate, such as during an assault involving pouring or throwing the water. Deliberate burns are especially dangerous because they may cover more of the body than burns from accidental spills.
Boiling water typically causes more severe burns than water that is just hot.
Beyond the water’s temperature, several factors can help indicate the severity of a burn, including:
- how long the boiling water has touched the skin
- how much of the skin has been exposed to the water
- how quickly the person can cool their skin after the burn
For many people, the first symptom of a boiling water burn is sudden, sharp pain. However, third-degree burns, or full-thickness burns, damage the nerves under the skin and might not hurt at all.
First-degree burn
A first-degree burn, or a superficial burn, is relatively minor. It only damages part of the first layer of skin, called the epidermis.
A superficial burn happens when boiled water lightly splashes on a person, such as while they are cooking, or when boiling water touches the skin very briefly.
Symptoms of a first-degree burn include:
- immediate pain that may last for several hours
- pink or red skin
- peeling as the burn heals
- dry-looking skin
Second-degree burn
A second-degree burn damages the epidermis and the top of the second layer of skin, called the dermis. Another name for this injury is a partial-thickness burn. These burns are more serious.
They may happen when boiling water remains on the skin for a longer period.
Some symptoms of a second-degree burn include:
- pain that lasts for days or weeks
- wet, watery-looking skin
- blisters
- red, pink, or white skin under blisters
These burns typically take 2–3 weeks to heal. Sometimes a person needs a skin graft to treat them. Second-degree burns often leave a scar, which may fade over several years.
Third-degree burn
A third-degree burn, or full-thickness burn, is the most serious type. It penetrates all layers of the skin.
It can cause serious infections and may even be fatal if a person does not receive treatment. Immersion in boiling water for a prolonged period can cause a third-degree burn.
Some symptoms include:
- no pain, or pain that quickly goes away
- signs of illness, such as fever and weakness
- very damaged-looking skin
- white, pink, or red skin
- grey or black areas of skin
Third-degree burns may require hospitalization. A person may need skin grafting, surgery, antibiotics, or a combination.
First-degree burns typically heal with the right home treatment.
Second-degree burns that cover large areas of the body and third-degree burns usually require professional evaluation and treatment. It can take weeks or months to recover.
Some potential complications of severe burns include:
- swelling
- severe scarring
- fluid loss, when a large area of the body is involved, and this can be fatal
- infections that can eventually travel to the bloodstream and become severe and possibly fatal
If a person appears very ill after a burn or the burn covers a large area of the body, seek immediate medical care — even if the wound does not look serious or the person is not in pain.
Always see a doctor for burns in babies and children.
Share on PinterestTo help prevent scalding during showers and baths, a person can try turning down the temperature of water heaters.
To reduce the risk of boiling water burns:
- Boil water and other liquids toward the back of the stove, where they are less likely to splash or spill, and where pots and pans are less likely to be knocked over.
- Set down hot drinks at the far end of a counter or table to reduce the risk of spilling.
- Turn down water heaters to reduce the risk of scalding during showers and baths.
- Teach children never to toss hot water, even as a joke.
- Assume that pots, kettles, and other kitchenware are hot after being on the stove, even if the stove is now off. Boiling water can take a long time to cool, as can the stove, even when its light is off.
- Cover boiling water to prevent splashes.
Boiling water burns are common accidents. Even minor scalds can be painful for several hours or even days.
Running burned skin under cold water as soon as possible and for at least 10 minutes is the best way to cool the skin and ease pain.
Prompt treatment reduces the risk of serious complications and, in the case of severe burns, may even save a person’s life.
Last medically reviewed on September 19, 2019
- Dermatology
- Emergency Medicine