How to Use a Mercury Thermometer

In a mercury-in-glass thermometer, a glass tube is crammed with mercury and a typical scale is marked on the tube. With changes in temperature, the mercury expands and contracts, and therefore the temperature is often read from the size. How to Use a Mercury Thermometer general.


Mercury thermometers are often wont to determine body, liquid, and vapor temperature. Mercury thermometers are utilized in households, laboratory experiments, and industrial applications.

Accurate body temperature readings can make a difference in treatment decisions. Use a mercury thermometer is easy but requires a bit of practice and skill.

Before Reading a Glass Mercury Thermometer

Because different models may have slightly different reading methods, one should first read manufacturer directions that come with all mercury thermometers. The following are general guidelines for many of the mercury glass thermometers:

Standard precautions like washing hands and wearing gloves if appropriate.

Handle with care to prevent thermometer from chipping or breaking.

Remove the probe cover and/or wipe the thermometer with a dry tissue from the stem to the bulb. Do not use an alcohol swab before reading the temperature reading.

Remove cover. Wipe the thermometer with a dry tissue from the stem to the bulb. Do not use alcohol swabs before reading the temperature.

Hold the thermometer at eye level and parallel to the floor.

Before Reading a Glass Mercury Thermometer

How to Read a Mercury Glass Thermometer?

Reading a Mercury Glass Thermometer properly is important, both reception and hospital. Accurate checking of blood heat is significant for determining the course of treatment or medication. One should read the mercury-in-glass thermometer immediately after taking the temperature. The temperature should be read to the closest line.

In a Fahrenheit thermometer:
Long lines indicate 1 degree.
Short lines indicate 0.2 degrees.
While in a Celsius thermometer:
Long lines indicate 1 degree or 0.5 degrees.
Short lines indicate 0.1 degrees.

Most of the mercury-in-glass thermometer, though, have dual scales.

One should be careful while reading temperatures between 100 degrees and 101 degrees because many people mistakenly record or report a tenth of a degree as a whole degree. For example, 100.2 degrees is between 100 and 101 while 102 degrees is between 102 and 103. Avoid mistakes because it could end in inappropriate therapy.

Read Mercury Thermometer at Eye level
Long lines on the Fahrenheit scale indicate 1 degree
Short lines on Fahrenheit scale indicate 0.2 degree
Read Celsius scale to nearest 0.1 degree
Read temperature to nearest lines

After taking the temperature, hold the thermometer up to a light where you can see the mercury line and the numbers.

Rotate the thermometer until you can clearly see the number and the lines between the numbers, much like on a ruler.

The point where the mercury ends is what the temperature is.

Most of the mercury-in-glass thermometer, though, have dual scales.

How to Check a Temperature Under the Tongue (Orally)?

Shakedown the mercury during a glass thermometer before placing it under the tongue. Do this by holding the thermometer firmly and flicking the wrist until the mercury reads at or below rock bottom number. Ensure the thermometer is far away from people and objects before shaking.

Now, place the bulb end of the thermometer under the tongue and ask the person to shut his mouth and breathe through his nose. The thermometer must stay under the tongue for a minimum of a moment to 2 minutes.

When an Oral Temperature should not be taken?

Avoid measuring blood heat under the tongue if the person is:
Infant or child (under the age of 6)
Injured or bleeding orally/has pain and/or sores in the mouth
Unable to shut the lips or had surgery within the mouth recently
Experiencing chills or rigors or if her teeth are chattering
Having difficulty in breathing or receiving oxygen via a mask
Using a nasogastric tube for feedings
Unable to take commands, confused, combative, or uncooperative
Unconscious or not responsive or on seizure precautions

DP20 – Mercury Basal Thermometer (°F)

Note: Basal thermometers are different from regular fever thermometers and used only by WOMEN to notice basal blood heat that happens with ovulation.

NET Basal mercury-in-glass thermometer is an accurate device to chart basal blood heat of girls to predict their fertile phase or ovulation (three days).

Basal thermometer, thus, helps women determine when they ovulate and thereby dramatically increase the chances of conceiving and falling pregnant. In this way, they can plan either to conceive or take precautions.

DP20 - Mercury Basal Thermometer (°F)

A woman is vulnerable to conceive during 3 days of ovulation and the NET Basal mercury-in-glass thermometer can indicate lately.

With ovulation body temperature increases due to an increase in hormone progesterone and by a precise recording of your body’s resting temperature first thing in the morning and at the same time each morning, you can know when ovulation takes place in your cycle.

Made from top quality capillary with lens front in Jena normal glass.

Suitable for oral (sub-lingual) and rectal use.

Temperature Range:
95° – 100°F Subdivided in 0.1°F

Household Uses of Mercury Thermometers

Common household uses of mercury thermometers include fever thermometers and oven, candy, and meat thermometers.

Fever Thermometers

Mercury fever thermometers are made of glass the size of a straw, with a silvery-white liquid inside. They are common in many households, schools, and medical facilities. There are two general sorts of mercury thermometers that measure body temperature:

Oral/Rectal/baby thermometers, containing about 0.61 grams of mercury
Basal temperature thermometers (used to track slight changes in body temperature), containing about 2.25 grams of mercury

Is There Mercury in My Thermometer?

If there is no liquid in your thermometer, for example, if it uses a metallic strip or coil to measure temperature (like most meat thermometers do), it is not a mercury thermometer.
If the liquid in the thermometer bulb is any color other than silver, it is not a mercury thermometer.
If the liquid in your thermometer bulb is silver, then the liquid might be:

Mercury, or
A non-toxic compound that looks similar to mercury.

We also have a detailed review on Normal Baby Temperature Armpit in case if you want to check that out! and other articles.

Leave a Comment

Your email address will not be published. Required fields are marked *

Show Buttons
Hide Buttons