A medical thermometer is an indispensable item in every home medicine cabinet, so what are the different types of thermometer? What is the best measuring device among them? Discover the advantages and disadvantages of each of them.

thermometer thermometer

Mercury thermometers were once the only available option for measuring temperature and, due to some safety concerns (mercury poisoning), are no longer widely available.

It depends on the presence of mercury inside a glass tube that contains a different temperature reading. When the device is placed under the tongue, the mercury begins to expand due to the high temperature until it reaches the body temperature, and once the mercury stops, the corresponding reading is the body temperature.

Features of the thermometer to measure the temperature

Thermometer features include:

• It provides an accurate temperature reading and can be used orally or under the arm.
• Does not require batteries.

Disadvantages of a mercury thermometer

The disadvantages of the mercury measuring device are as follows:

• Since it is made of glass, it can easily break, allowing toxic mercury to escape.
• It may also cause cuts or shards of glass if it breaks.
• Because it contains mercury, it should be disposed of safely, not thrown in the trash.
• It can be hard to read, and it has to stay in place for 3 minutes.

digital thermometer

Digital thermometers are the most common type, which give quick and accurate results, and are easy to use, inexpensive, and readily available.

These devices are usually made of flexible plastic with a sensor on one end and a viewing window on the other, and are designed to measure oral (sublingual) or underarm temperature.

The digital thermometer works by touch, where the element responsible for measuring the temperature is the electronic circuit called the thermistor.

Advantages of a digital thermometer

Features of the digital thermometer include:

• The device provides accurate readings in about 1 minute or less (about 10 to 15 seconds for a measurement).
• Safer than mercury thermometers and does not consist of breakable glass.

Disadvantages of a digital thermometer

The disadvantages of the digital thermometer are as follows:

• The main disadvantage of this type is the presence of a tip made of nickel, which can be dangerous for those with nickel allergies, in which case a thermometer with a gold-plated tip or another type can be used to measure the temperature.
• The readings will not be accurate if they are taken too close to eating or drinking; Because the results may change due to the temperature of the food or drink, it is best to wait at least 15 minutes after eating or drinking.
• It has susceptibility to electromagnetic fields from medical devices and communication devices (cell phones), which may affect the accuracy of the results.
• Batteries must be replaced periodically, and the metal tip needs to be disinfected after each use.

ear thermometer

Digital ear thermometers measure the temperature inside the ear canal through infrared technology. These devices measure the temperature of the tympanic membrane inside the ear.

Eardrum readings range from 0.3°C to 0.6°C higher than oral temperature readings, which range from 36.4°C to 37.4°C.

Advantages

The advantages of the ear thermometer include:

• This type is the best thermometer for children.
• Quick to capture body temperature and easy to use.

Defects

The disadvantages of the ear meter are as follows:

• Expensive.
• Due to the size of the ear canal, this device is not recommended for infants under 6 months of age.
• It does not measure body temperature accurately if it is not properly placed in the ear.
• It may give a low reading if there is a lot of wax inside the ear.
• It may not fit in a small or curved ear canal.

Forehead thermometer

Forehead thermometers also use infrared technology to measure temperature, by capturing the temperature of the superficial temporal artery (a branch of the carotid artery).

These devices are new and have become very popular for taking people’s temperatures in airports, stores and stadiums; They do not require any physical contact while the temperature readings are taken.

It is worth noting that this type of thermometer gives forehead temperature readings about 0.6°C lower (cooler) than oral temperature readings.

Advantages

The advantages of the forehead thermometer include:

• Provides quick readings within several seconds.
• It can be used on infants, children and adults.

Defects

The disadvantages of forehead thermometers, which make them not as accurate as digital thermometers, include the following:

• Forehead thermometers must be placed accurately and according to the manufacturer’s instructions, or they will not provide the correct reading.
• Readings can be affected by external factors, including air currents, wind, and direct sunlight.
• Wearing certain clothing, such as hats or heavy coats, may distort the results.

pacifier thermometer

Pacifier thermometers are primarily designed for children older than three months, especially if the child is comfortable using a pacifier, as this may make it easier to determine body temperature.

Features of a pacifier thermometer include ease of use which is the biggest benefit of pacifier thermometers.

The disadvantages of pacifier thermometers include:

• It should remain in the mouth without moving, so that the child remains still for up to 6 minutes when the temperature is taken.
• Additionally, it provides approximate body temperatures, not an exact reading.