At what temperature in degrees Celsius can discharging materials cause burns to humans?

The temperature range for the sense of warmth in human skin is between 20°C and 47°C; when the temperature is around 35°C, the human skin experiences a sense of warmth； When the temperature exceeds 45°C, a hot or even burning sensation is produced ； When the temperature reaches 47°C, there is a burning pain sensation ； Blisters form due to burns when the temperature is above 50°C ； If it comes into contact with human skin at 60°C for one minute, it will cause a third-degree burn. But not all burns are caused by hot objects such as boiling water or hot soup; heating devices like hot water bags can also cause burns if used improperly, even if their temperature is not high. 　　There are two factors that cause burns: one is the temperature of the heat source, and the other is the duration of exposure. Generally, most people are only vigilant about the former and fail to realize the importance of the latter. The reason why burns can occur even at low temperatures is that the heat source acts on the skin for an extended period of time, allowing heat to gradually penetrate into the soft tissues and cause burns.

Low-temperature scalding is caused by exposure to a temperature of around 50°C for an extended period in certain areas of the body, allowing heat to gradually penetrate the subcutaneous soft tissues.

When working on designs in many design institutes, to ensure safety, insulation is required when the surface temperature of the equipment exceeds 45 degrees; personally, I think there’s no problem at temperatures below 45 degrees

It’s not a problem with heat retention; it’s that the material I’m dealing with needs to be removed, and someone needs to pick it up. I’m worried that something might splash out during this process and cause burns to people. What temperature is high enough to cause burns?

The main thing is whether a written source can be found for this temperature; I need it as a basis for the design

Then this is no longer a matter of burns; it’s a matter of personal safety. Safety is not determined by whether there are burns or not. Since a temperature of 45 degrees already causes a burning sensation, the temperature should be below 45 degrees, or even lower

Yes, it refers to personal safety. Is there a source for this figure of 45? Are there any books or materials that describe it?

A few days ago, there was a post about the surface temperature of the insulation on the outer tube, and it actually concluded that the surface temperature of the insulation metal sheet on the outer tube could reach 50 degrees. Not to mention how large the heat loss is – it can cause burns!

This mainly depends on the temperature and duration of exposure of the body part. For example, in the first case, if the hands are exposed to a temperature of 45–55 degrees for an extended period of time, they can still get burned; at temperatures above 55 degrees, blisters will form within a short time, and the higher the temperature, the more severe the burn will be.

So if I’m writing an operation manual or establishing manufacturing procedures, what should this emission temperature be set at? 45 or 50?