Having a dependable medical thermometer at home can be extremely beneficial. The ability to determine whether or not someone has a fever provides critical information about important next steps in their care. There are numerous contact and non-contact thermometers to choose from. The ages of your family members, as well as your personal preferences, can help you decide which types of thermometer to purchase. It’s important to understand how a thermometer works, just like any other device in your home. Not all types of thermometer operate in the same way or provide the same temperature readings.
The thermometer is the universal temperature measuring instrument. People frequently mix up the terms temperature and heat. For example, how do you explain an object’s hotness? What is the basis or measure of that heat? The temperature is the answer. Heat is a type of energy with the unit Joule. Temperature, on the other hand, is a measure of that heat. This means that if the heat is higher, the temperature is higher as well. But how do we determine the temperature? To determine the temperature of any object, we use a thermometer.
The temperature is defined as the measurable extent of hotness or coldness. It’s a graphical representation of heat. Temperatures are measured in various units, including Celsius, Kelvin and Fahrenheit. There are various types of thermometers that are classified based on their applications. For example, one set of thermometers is used to measure body temperature, while another set is used to measure boiling and freezing points during experiments.
How a thermometer works?
When you look at a regular outside bulb thermometer, you’ll notice a thin red or silver line that grows longer as the temperature rises. It is now hotter. In cold weather, the line collapses. This liquid is occasionally colored alcohol, but it can also be a mercury. Mercury is a metallic liquid. Both mercury and alcohol are toxic.
When heated, they grow larger, and when cooled, they shrink. The liquid has no place in the glass tube of a thermometer to go but up when it’s hot and down when it’s cold. The glass tube is marked with numbers that are placed alongside it. Numbers are placed alongside the glass tube that mark the temperature when the line is at that point.
Types of Thermometer
Thermometers come in a variety of shapes and sizes to meet the needs of the user. They are mostly used to measure the temperature of objects, as previously stated (living and non-living). As a result, only one type of thermometer is used to measure body temperature. However, in studies or laboratory testing, a different set of thermometers is used to determine boiling and freezing points.
Thermometers are classified into two types based on their function:
- Clinical Thermometers
- Laboratory Thermometers
Clinical thermometers, also known as medical thermometers, are designed for clinical use only. These thermometers are used to determine the temperature of the body. A basic clinical thermometer is a long, narrow glass tube with a mercury-filled bulb at one end. The mercury level indicates the temperature of the human body. Mercury, on the other hand, is a highly toxic element. As a result, analogue thermometers have given way to sophisticated digital thermometers that can monitor the body’s temperature without ever touching it. It is always a good idea to sanitize these thermometers before using them.
The body temperature is 37 degrees Celsius on average. This can range between 35 and 42 degrees Celsius. As a result, the temperature range of clinical thermometers is 35 to 42 degrees Celsius. The following are the various types of clinical thermometers that we use on a daily basis to assess body temperature:
Most digital thermometers use heat sensors to determine the temperature of the human body. They also include an electronic circuit and a display screen for displaying temperature readings. They can be used to obtain readings from the rectum, the tongue, or the armpit. Digital thermometers are a more advanced type of thermometer than traditional thermometers. These types of thermometer are thought to be the most accurate when used correctly. They are also simple to use, inexpensive, and widely available.
Electronic Ear Thermometer
Types of thermometer: Infrared technology is used by electronic ear thermometers to determine body temperature from inside the ear canal. Tympanic thermometers are so named because they use the tympanic membrane within the ear to measure temperature. This thermometer is ideal for children. They are, however, expensive, and if the thermometer is not properly placed in the ear or if there is too much wax inside the ear, the body temperature may not be accurately measured. To determine body temperature, electronic ear thermometers use infrared energy emitted by the heat source. As a result, these thermometers can quickly detect body temperatures.
To read heat, forehead thermometers, like electronic ear thermometers, use infrared technology. They measure the temperature of the superficial temporal artery, a branch of the carotid artery, with infrared sensors. These thermometers are modern and are widely used to measure people’s temperatures in airports, train stations, shopping malls, and stadiums. The main reason for their popularity is their non-contact behavior. This means that no physical contact is required when taking temperature readings with a forehead thermometer. Forehead thermometers are not as accurate as standard digital thermometers, and their temperature readings are typically 1°F (0.6°C) lower.
Types of thermometer: Pacifier thermometers are intended for newborns aged three months and up. If a baby is comfortable with a pacifier, this may be the simplest way to determine his or her body temperature. Pacifier thermometers are simple to use but inaccurate, recording only approximate body temperatures. They need the baby to be calm for a few minutes to monitor the body temperature, which may be difficult. This can cause temperature readings to be inaccurate.
Plastic Strip Thermometer
Plastic strip thermometers are ineffective for detecting body temperatures because they do not produce precise temperature readings. They can be used to determine whether or not a person has a fever. We must place the plastic strip thermometer on our forehead to use it, and the colors on the strip will change in response to our body temperature. If the color changes to dangerous, you almost certainly have a fever. These thermometers are untrustworthy. They are also single-phase thermometers that can be discarded.
Types of thermometer: Mercury thermometers, which were once the only way to monitor body temperature, are the most basic thermometers. They are the most accurate thermometers and are used similarly to digital thermometers. These thermometers, on the other hand, are battery-free and lack any electrical circuits or displays. Mercury thermometers are made up of a glass tube that contains a range of temperature readings. One end of the glass is filled with liquid mercury.
When we place this thermometer under our tongue, it starts to rise in response to our body temperature. Body temperature is the appropriate reading when the mercury reaches the end of its journey. Mercury thermometers, on the other hand, are no longer frequently used due to safety concerns (mercury poisoning) and are banned in several countries.
There can be a question that why thermometer use mercury, not any other liquid? We all know that most metals conduct heat and electricity well and are solid at room temperature. At room temperature, mercury is the only metal that is liquid. It is used in thermometers because it has a high coefficient of expansion, which allows it to move easily in thermometers as temperatures change. Mercury has a high boiling point, making it suitable for measuring higher temperatures. A mercury thermometer consists of a glass tube filled with mercury and a standard temperature scale. The mercury expands and contracts in response to temperature changes.
Because clinical thermometers cannot be used to measure temperatures other than those of the human body, specialized thermometers are available to do so. Laboratory thermometers, in particular, are used to measure temperatures other than body temperatures. These thermometers are also known as lab thermometers. In labs and testing, they aid in the measurement of boiling points, freezing points, and the temperatures of a variety of other objects.
Laboratory temperatures should only be used in laboratories and never in clinical or medical settings. Furthermore, maximum-minimum thermometers help weather forecasters determine the highest and lowest temperatures at any given location. The temperature range of laboratory thermometers is typically -10 to 110 degrees Celsius. Laboratory thermometers come in a variety of sizes and shapes to accommodate a wide range of temperature measurements. Some of the most frequent types are as follows:
As the name implies, liquid-in-glass thermometers are made with a sealed glass containing a liquid such as mercury or red alcohol. As the temperature rises or falls, the volume of liquids in thermometers changes. The liquid expands in response to rising temperatures. The level of rinsing liquid in the glass tube also helps to indicate the temperature. Because they have a glass tube, these thermometers are fragile. As a result, they’re kept in protective enclosures with temperature readings written on them. Furthermore, because they do not require a power supply, liquid-in-glass thermometers are convenient, inexpensive, and ideal for locations with an electrical problem.
Bimetallic Strip Thermometer
Types of thermometer: Bimetallic strip thermometers are made from two different metals. When the temperature rises, the metals become entangled and expand at different rates. The two metals used in these thermometers also expand to different lengths. As a result, the bimetallic strip bends or curls towards the side with the lower thermal expansion coefficient. When the bimetallic strip moves, it deflects a pointer across a calibrated scale, allowing the temperature to be determined. Furthermore, bimetallic thermometers are strong, inexpensive, and simple to install and use.
Bimetallic strip thermometers are constructed from two distinct metals. The metals become entangled and expand at different rates as the temperature rises. These thermometers’ two metals expand to different lengths as well. As a result, the bimetallic strip bends or coils towards the side with a lower coefficient of thermal expansion. The vibration of the bimetallic strip deflects a pointer across a calibrated scale, allowing the temperature to be determined. Bimetallic thermometers are also long-lasting, inexpensive, and simple to install and use. The temperature that was measured is displayed on the instrument. These thermometers are commonly used to measure temperatures up to 2800 K. Thermocouple thermometers are also known as thermal junction thermoelectric thermometers. Visit this website for more information on thermocouple thermometers.
Types of thermometer: Pyrometer thermometers, also known as pyrometers, are remote-sensing devices that help with temperature measurement at a distance. The thermal radiation emitted by these thermometers is usually used to determine the temperature of the object. One of the most significant advantages of these thermometers is that you do not need to touch anything. As a result, pyrometers are ideal for monitoring the temperatures of moving objects or surfaces. They’re also useful for determining the temperatures of items that can’t be touched because of their intricate structure or high temperatures. Temperatures above 2000 degrees Celsius are measured using pyrometers.
Platinum Resistance Thermometer
In platinum resistance thermometers, a platinum wire is used to monitor the temperature. The wire is linked to an electrical resistance that varies in response to temperature. This means that as the temperature rises, so does the resistance of the material used in these thermometers. Platinum resistance temperatures are used to detect the outside temperature. Despite their high temperature precision, these thermometers are a little slow. These thermometers are commonly used to measure temperatures ranging from 500 to 2300 degrees Celsius.
The probe thermometer is one of the most common and widely used types of thermometers. They are primarily used to take real-time temperature readings of food and liquid samples. These thermometers’ quick temperature readings make them ideal for hygiene testing in retail outlets and food industry laboratories. Probe thermometers typically have a pointed tip that aids in penetration and immersion. The two types of probes available are fixed probe thermometers and wired probe thermometers.
Which type of thermometer is the most accurate?
Using a reliable medical thermometer to check your temperature can be very helpful in managing illness at home. And nowadays, most thermometers provide accurate results in a matter of seconds. So, how do you go about picking the best one for you and your family? Digital thermometers provide the most accurate readings of body temperature out of all types of thermometer. However, the best thermometer is one that is simple to use and accurate. It is also advantageous if your thermometer is manufactured by a reputable company. Rectal thermometers are still considered the most accurate for babies and children by many doctors, but oral and forehead thermometers are also reliable and more convenient to use.
How to use a Thermometer?
A digital thermometer is one way to check your temperature. These are available at supermarkets and pharmacies. To use a digital thermometer, follow these steps:
- Rinse the tip after cleaning it with cold water and soap.
- Turn on the thermometer.
- Place the tip of your tongue against the back of your mouth.
- Put your lips together around the thermometer.
- Wait for it to beep or flash.
- Examine the temperature reading on the display.
You can also place a digital thermometer in your armpit. Maintain a tight grip on your arm until the thermometer beeps or flashes.
Uses of thermometer
Thermometers utilize a range of physical effects to measure temperature. Temperature sensors are used in a wide variety of scientific and engineering applications, especially measurement systems. Temperature systems are primarily either electrical or mechanical, occasionally inseparable from the system which they control (as in the case of a mercury-in-glass thermometer).
- Cooking thermometers are important for determining if a food is properly cooked. In particular meat thermometers are used to aid in cooking meat to a safe internal temperature while preventing over cooking. They are commonly found using either a bimetallic coil, or a thermocouple or thermistor with a digital readout.
- Indoors, thermistors are used in climate control systems such as air conditioners, freezers, heaters, refrigerators, and water heaters.
- Galileo thermometers are used to measure indoor air temperature, due to their limited measurement range.
- Liquid crystal thermometers (which use thermo-chromic liquid crystals) are also used in mood rings and used to measure the temperature of water in fish tanks.
- Fiber Bragg grating temperature sensors are used in nuclear power facilities to monitor reactor core temperatures and avoid the possibility of nuclear meltdowns.
- Conventional thermometers cannot measure the temperature of an object which is smaller than a micrometer, and new methods and materials have to be used. Nano-thermometry is used in such cases. Nano-thermometers are classified as luminescent thermometers (if they use light to measure temperature) and non-luminescent thermometers (systems where thermometric properties are not directly related to luminescence).
- Thermometers are used in roadways in cold weather climates to help determine if icing conditions exist.
- Thermometers are important in food safety, where food at temperatures within 41 and 135 °F (5 and 57 °C) can be prone to potentially harmful levels of bacterial growth after several hours which could lead to foodborne illness. This includes monitoring refrigeration temperatures and maintaining temperatures in foods being served under heat lamps or hot water baths.
- Candy thermometers are used to aid in achieving a specific water content in a sugar solution based on its boiling temperature.
- Aircraft use thermometers and hygrometers to determine if atmospheric icing conditions exist along their flight path. These measurements are used to initialize weather forecast models.
- Thermometers are used in roadways in cold weather climates to help determine if icing conditions exist and indoors in climate control systems.