How to measure body temperature with mercury thermometer?

Are you feeling under the weather? Are you unsure if you have a fever or not? Well, it’s time to take your temperature with an oldie but goodie – A Mercury Thermometer! That’s right; we’re going back in time!

Before we start measuring body temperature, let us first understand what are thermometers out there.

Types of thermometer

There are various types of thermometers available on the market:

  • Glass thermometer
  • Digital thermometer
  • Ear (tympanic) thermometer
  • Fever strip thermometer
  • Pacifier thermometer

But today, we will explore how to use a mercury-based glass thermometer. So sit tight and read closely because this information might come in handy someday!

Getting Started

First things first, wash your hands thoroughly using plenty of soap and warm water. You don’t want bacteria from your fingers tainting the results.

Next, retrieve one (that’s right just one) mercury-based glass thermometer from a reputable medical supply store. It is important that you get reliable equipment for accurate results.

Be careful when handling the instrument as it can break easily. If it breaks DO NOT try to clean up yourself instead call hazardous waste pickup as they handle this kind of material safely.

Preparing The Thermometer

  1. Shake down:

Hold the thermometer at its end opposite where the bulb is located and give it a quick flicking motion downwards until bubbles appear within fluid column inside which means its ready for use.
2. Sanitize:

Cleanse the silver part (the stem), usually alcohol or hydrogen peroxide does a great job on cleaning without damaging any sensitive parts like mercury.

Measuring Body Temperature

Now that our trusty old-school tool has been prepared let’s learn how to use it properly:

Step One: Placement Positioning

Place your glass/mercury-based thermometer under your tongue. Yes, you heard that right, it goes down there! Hold the instrument as still as possible.

Important: Do not chew on it or mess around with the reading whilst holding in place because we want to record an accurate temperature reading.

Step Two: Time Your Measuring Device

It is suggested mercury thermometers remain undisturbed for 3-5 minutes after placement to ensure accurate measurement calculation; however make sure you are using a timer device for it or else one might get lost in thought during this time!


After waiting for the appropriate amount of time to acquire an accurate reading, carefully remove and check readings by looking up close at markings. A person’s baseline body temperature can range from 97°F(36°C) up to about 99°F (37°C). Ideally, a healthy person should have their body temperature between these ranges but if its over than go see licensed medical personnel.

How To Clean The Thermometer

Our final step covers cleaning our measuring equipment upon usage:

  1. Wash

Wash your hands thoroughly.
2. Sanitize

Once washed sanitize both bulb silver part-stem of thermometer either via alcohol before putting back inside casing or cupboard until future use.

Don’t forget that every part must be dried since moisture may affect readings causing false temperatures.


Now that you know how to measure body temperature with a Mercury Thermometer like those old-timers used during childhood fevers back then , keep practicing until confident enough doing measurements easily!

Remember- handling any sort of medical equipment requires finesse so practice basic cleanliness techniques when handling sensitive material such as glass thermometers!

Health always comes first; whether checking on yourself, family members or colleagues just remember – stay safe everyone and feel better soon!