Equipments Used to Measure Body Temperature

Glass-bulb thermometers, historically the standard for temperature measurement, are now banned in many countries due to the hazardous effects of mercury. If the glass bulb breaks, it poses a risk of mercury exposure and unintended injury to patients. These safety concerns have led to their replacement with safer alternatives.

Digital and electronic thermometers are battery-powered devices that display numerical temperature readings. They feature a rechargeable display unit, a temperature-processing probe covered by a disposable probe cover, and can assess oral, rectal, or axillary body temperature in 1 to 60 seconds. Some models automatically convert readings between Fahrenheit and Celsius.

Tympanic membrane thermometers use infrared sensors to measure heat emitted by the tympanic membrane, providing readings in 1 to 3 seconds. The otoscope-like speculum is placed securely in the ear canal with a probe cover. This rapid, non-invasive method makes assessing body temperature tympanic membrane measurement practical in clinical settings.

Temporal artery thermometers use the heat radiated by the skin above the temporal artery to determine body temperature. These battery-powered devices display temperature readings and offer a non-invasive measurement method. They are commonly used for assessing body temperature temporal artery sites in both clinical and home settings.

Disposable single-use thermometers are unbreakable and eliminate the risk of cross-infection since each thermometer is used only once. They are ideal for patients on isolation precautions and detect temperature in seconds. Chemical dot thermometers, a type of disposable thermometer, change color to reflect temperature and are safe for use with children.

Chemical dot thermometers are temperature-sensitive patches or tapes placed on the stomach or forehead that change color to reflect body temperature. The Celsius version has 50 dots, each representing a 0.1°C increase from 35.5°C to 40.4°C, while the Fahrenheit version features 45 dots with 0.2°F variations. If abnormal temperature is indicated, a traditional thermometer should verify the reading.

Infrared thermometers measure temperature by detecting infrared energy reflected from the skin's surface, offering a non-contact measurement method. Unlike contact thermometers such as digital or glass-bulb devices, infrared thermometers do not require direct contact with the patient. This makes them useful for rapid screening and reducing cross-contamination risk.