One of the basic hospital equipment units is the thermometer. It is an instrument with which anyone can get a reading of body temperature. Also, it is the preliminary diagnostic device that helps a doctor or any healthcare professional to check fevers. In the old days, a mercury-based thermometer was used.
However, since mercury thermometers are difficult to read, manufacturers introduced digital thermometers. From the name itself, you can understand that these units don’t require alcohol or mercury to determine your body temperature. They have sensors and appropriate readings are shown.
In this article, we will shed light on hospital thermometers, their working principles, types, and so on.
Working Of A Mercury Thermometer
In a mercury thermometer, you will see a small tapered bulb at the bottom. Here, the mercury liquid is present. You can identify it by its silver color. Along the thicker portion of the glass casing, a scale is there. This scale is calibrated manually and markings are present in terms of Fahrenheit.
When the thermometer’s bulb is exposed to heat, the mercury absorbs the energy and expands. It shows similar behaviour to all other liquids, i.e, expansion in volume on subjection to heat. After that, it will rise along a thin capillary tube. Since mercury is opaque, you can easily mark it. It is still one of the most preferred hospital thermometers. Hence, it is used in many clinics, pharmacy shops, and small district hospitals.
Working Principle Of A Digital Thermometer
Another type of hospital thermometers you will find is a digital thermometer. They do not have any capillary tube, mercury or glass casing. Rather, a small screen will be present where the digital reading will be shown. A small button is also there that acts as a power button.
In this type of thermometer, there is an electrode circuit. It absorbs heat from your body and current is generated. The amount of current flowing through the electrode gives the reading. But before that, the analogue value of the current is converted into a digital value that determines your temperature.
Mercury VS Digital Thermometer
Even though both these thermometers provide body temperature readings, there are several differences between them. In this below section, we have described some of the major points that set them apart from each other.
- Mercury thermometers completely rely on the expansion coefficient of the liquid. Therefore, if the element is not pure, readings will be abnormal. However, in digital thermometers, the calibrations are done based on circuit readings. Therefore, these values are more accurate.
- Digital thermometers have electronic circuits that can malfunction at any time. But if we talk about the mercury ones, chances of malfunctions are rare.
In this article, we have presented the fundamental knowledge you require to decide which thermometer is better. Both have pros and cons. Therefore, you need to weigh them properly so that your decision can meet your requirements properly.