How does a mercury thermometer work?

how does a mercury thermometer work

Mercury thermometers have been around for quite some time and still today. In almost every house a mercury thermometer was available. Over time they have been discontinued since it has been discovered that it can be very dangerous if it breaks. There are many people who do not know well how a mercury thermometer works. This is one of the reasons why it has also been banned since it does not compensate because of its dangerousness and its risk when using it.

Therefore, in this article we are going to show you how a mercury thermometer works.

Main features of mercury thermometers

It is a temperature measurement instrument that consists of a bulb from which a thinner tube made of glass extends. Inside the bulb is the metal mercury. This particular metal has been chosen since its volume changes depending on the temperature. He The instrument has numbers that mark the temperature values. Depending on these values, the volume will rise or fall. This metal was used to be able to have a greater facility when changing its volume and better express the data.

Given its ease and effectiveness when it comes to measuring temperatures, it became a very widespread tool throughout the world. He price of a mercury thermometer it was quite affordable by the entire population. The science that studies the temperature known as thermology was tremendously advanced thanks to the mercury thermometer. The range of temperatures that it can host is quite large.

How a mercury thermometer works

use the thermometer

Once we know what this type of tool is let's see how it works step by step. Mercury thermometers have numbers that indicate temperature values. These numbers are measured by a very thin line that is drawn in the center. This line is the one in charge of indicating the value of the temperature that is being measured. If we want to use it to know body temperature, the most normal thing is to place the bulb under the tongue, in the rectum or in the armpit. In this way, we can check for fever by measuring body temperature.

Let's see step by step how a mercury thermometer works:

  • Cleaning the bulb: First of all, clean the bulb on the metal part of the thermometer with a cotton pad that is soaked in antiseptic alcohol. In this way, we can disinfect the part that will mostly come into contact with our body.
  • We energetically activate mercury thermometer: To do this, we must use it on the opposite side to the bulb. Thanks to this movement we can make any mercury residue that has remained go down and guarantee that the indicated temperature is correct.
  • We place the thermometer in the armpit: the bulb must be right in the center of the armpit to be able to measure the temperature values ​​well. Next, we leave the arm in the lap without moving it while we allow the temperature to rise the mercury and check if you have a fever.
  • We wait about five minutes: roughly the time it takes for the mercury to rise and indicate body temperature. It is important to time the time we are with the thermometer well, since this way we will avoid removing it prematurely.
  • Shake it again: To lower the mercury again, we must shake the thermometer again. Finally, the ideal is to keep it well in its case so that it does not break. We know that mercury metal is toxic and glass is quite brittle. It is also interesting to disinfect it again with alcohol before storing it.

How to read a mercury thermometer

how to use the mercury thermometer

Not only do you have to know how a mercury thermometer works, but also know how to interpret the data. To do this, you have to learn to read it correctly. After waiting the five minutes for the temperature to rise, we remove the thermometer and observe the center line. It is this line that helps us indicate body temperature. Depending on the value they have, we know whether or not we have a fever.

It is important to move the thermometer gently since if the mercury line is not seen clearly, it must be moved. If the line exceeds 37 degrees we know we have a fever. If it only passes a few tenths there is no need to worry. If the temperature is close to 40 degrees, it is best to re-measure the temperature or go to the doctor immediately.

How Mercury Thermometer Work: What To Do If It Breaks

One of the fundamental aspects is knowing what to do when a mercury thermometer breaks. If due to any accident it slips out of our hand and falls to the ground, breaking the glass, we must have a protocol for action. The ideal is ventilate the entire environment as much as possible to avoid breathing toxic fumes. This metal is toxic if breathed in and can cause brain damage, skin problems, stomach problems, etc.

Before going on to collect the little mercury balls that form when the thermometer breaks, we must put on masks and gloves to protect ourselves not to breathe the vapors. Also, any contact with the skin can lead to worse problems. Therefore, the ideal is to collect and check well that all the mercury pearls have been collected.

It is not at all recommended to flush the rest of the mercury down the toilet, since it contaminates more than 1000 liters of water unnecessarily.

Alternatives to these thermometers

alternatives to the mercury thermometer

There are some more interesting alternatives to the mercury thermometer, since it is not commercially available today. Let's see what the main varieties are:

  • Digital thermometer: It is one that is used with the same guidelines as a mercury thermometer.
  • Infrared thermometer: makes a temperature reading through the rays emitted by the skin. They are harmless to health.
  • Baby thermometers: They are pacifier-type thermometers that we can use to know if our children have a fever.

I hope that with this information you can learn more about how a mercury thermometer works.

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