Defined: The degree or intensity of heat or cold, with reference to some standard value. The temperature of two systems is the same when the systems are in thermal equilibrium.
Temperature controls our quality of life and the measurement of different types of temperatures are inter-related, especially when utilizing infrared thermal imaging for human temperature screening.
The average normal body temperature is generally accepted as 98.6°F (37°C). Recent studies have shown that the “normal” body temperature can have a wide range, from 97°F (36.1°C) to 99°F (37.2°C). A healthy person’s body temperature fluctuates throughout the day, being cooler in the morning and warmer in the afternoon. A core temperature over 100.4°F (38°C) is defined by medical experts as a fever caused by an infection or illness.
The normal temperature of skin is about 33 °C or 91 °F. The flow of energy to and from the skin determines our sense of hot and cold. Heat flows from higher to lower temperature, so the human skin will not drop below that of surrounding air, regardless of wind.
The area of the eye closest to the nose is the measurably hottest spot on the face. The temperature in this area can range from about 34 °C or 93 °F to 36 °C or 97 °F.
A thermal camera measures skin or external temperature, as it reads temperatures emitting from the skin and does not have the mechanism to enter the body like a medical thermometer.
The international standard for assessing the most accurate skin measurement is in the inner canthus or the warmest area on the face.
The ambient temperature is affected by summer heat, winter cold, rain and humidity. This affects the surface of the skin and thermal temperature calculations.
When as this question, what we mean is “Do you have a fever?” A core temperature over 100.4°F (38°C) is defined by medical experts as a fever caused by an infection or illness.
Infrared thermal imaging cameras can detect Elevated Body Temperature but displayed temperatures (even if they are claimed to be “accurate”) do not represent a person’s core temperature. There is a method to more accurately determine if a person has an elevated body temperature as compared to others in their environment. This a “Human temperature calibration” method with the infrared thermal camera.