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How to Check Room Temperature Without a Thermometer (And Is It Accurate?)

How to Check Room Temperature Without a Thermometer (And Is It Accurate?)

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There may be a reason why you need to know the temperature of a room. For instance, you may have a product that needs to be maintained at a particular room temperature or you might have a pet that can only survive in certain temperatures.

If you want to know the temperature but don’t have a thermometer, you will need to find another way.

The reality is that you cannot measure the exact temperature without a thermometer but you can use other items to make a close estimate. There are other scientific ways of measuring the temperature so you will be able to find a solution.

How to Check Room Temperature Without a Thermometer (And Is It Accurate?)

What Is Temperature?

The simple answer is that temperature is a measure of how hot or how cold an environment is. It can be measured with the Celsius scale (degrees C) or the Fahrenheit scale (degrees F). In addition, the Kelvin scale (degrees K) is used for scientific purposes.

To understand how temperature is measured, it is important to understand what makes things hot or cold. The kinetic energy of the atoms in a system is what creates temperature. The kinetic energy is how fast the particles move around.

In a colder room, the air particles move at a slower rate; however, in a warm room, the particles move faster.

How Does Humidity Relate to Temperature?

Condensation on Window

Humidity is the amount of water molecules in air. Hot air has a greater capacity to hold in water molecules whereas cold air holds fewer water molecules.

It stands to reason that humidity accompanies higher temperatures. This can help you determine the temperature in a room without a thermometer.

Why Do We Need to Know the Temperature?

If you need to know a specific temperature, it is going to be nearly impossible to find out the exact measure without a thermometer or other scientific tools.

However, if you simply want to calculate and approximate temperature or if you need to make sure that a room is within a particular temperature range, there are ways that you can calculate it.

You may have a pet, such as a chinchilla, that has a very thick coat and cannot tolerate temperatures above 80 degrees Fahrenheit without becoming stressed. In this case, you will need to ensure that your home is cooler than 80 degrees, which you can do without a thermometer.

You may have supplies or aerosols that require a range of temperatures for safety reasons and you can make sure that you are within range for this as well. There are reasons why we might need an estimate of the temperature and this is possible.

However, if you need to know the exact temperature, you will have to have a thermometer.

Assess How Warm or Cold You Are

Dog Under Blanket

Room temperature is considered to be between 72 and 76 degrees Fahrenheit. The reason for this is that human body temperature is approximately 98.6 degrees and the temperature of the skin is on average 72 to 76 degrees.

Room temperature is the temperature that is considered comfortable without having to put on extra clothing and without having to remove clothing.

If you walk into a room and the air temperature feels neither hot nor cold to you, it is likely between 72 and 76 degrees. Experiments and statistics indicate that 95 percent of human beings are comfortable in this temperature range.

The first way to determine the temperature is by this method, which should tell you if it is above or below this range.

If it is much hotter or much colder than room temperature, you may need additional items to determine a close approximation.

Too cold? Try these 6 Great Ways to Warm Your Bed (without an electric blanket).

Use Your Smartphone

Most people have smartphones and there are apps that you can download to let you know the temperature of a room. Smartphones are often equipped with sensors that they use to determine the temperature of the phone to protect it.

There are different apps you can download (on Android devices) that will use the sensors on your smartphone to determine the temperature in the room. Most of these apps will have a section where you can select the ambient temperature reading for the room.

Most of these temperature apps are free and they should give you the reading in Celsius and Fahrenheit. Some apps may be more accurate than others but they will give you a general idea of the temperature of the room.

Build a Thermometer

Wooden Thermometer

There are actually simple methods you can use to build a thermometer. If you want to know the exact temperature, you will need to calibrate your homemade thermometer with a real one before you use it.

To start, you will need some basic supplies. You should have the following on hand to build your thermometer:

  • Water
  • Rubbing alcohol
  • Empty plastic soda bottle
  • Red food coloring
  • Clear plastic drinking straw
  • Modeling clay

Now you are ready to start building. First, you should add equal parts rubbing alcohol and water to the bottle. You will fill it up about 25%. Then, add a few drops of red food coloring. You can mix it up by shaking the bottle.

Now you can take the straw and place it inside the bottle. Cover the top with the modeling clay to keep the straw in place. Do not close off the opening to the straw, but seal around it. Mark a line on the bottle where the water is.

You can test this thermometer by grasping the bottle with your hands. Heat makes the water rise. If you want to measure the changes in temperature, you will have to test your model with a real thermometer and take note of the height of the water in different temperatures.

The Verdict

The only way to really measure the temperature of a room in degrees is with a thermometer. However, if you download an app on your smartphone, you should be able to use the sensors on your phone to calculate the temperature of the room.

Another test is using your body and how the room feels. There are different sensations that can help you determine temperature and humidity level.

Most people find a room between 72 and 76 degrees to be just right, which is why it is called room temperature. If you are comfortable and do not need to add or remove clothing, your room is probably in this range.

If the room is very cold, you can use a cube of ice to determine if it is below or above the melting point of ice. Ice melts at 32 degrees F or 0 degrees C so if it does not melt, you know that it is less than this.

If it melts, you can use a formula to determine how long it takes to melt but this will require some scientific calculations. The faster it melts, the warmer the room is.

If the air in the room feels damp, there is high humidity. Normally, warmer air can hold more moisture so you will know that it is warm. If you want to have fun with it, you can build a thermometer.

You just need to test your thermometer with an actual thermometer and then you can measure the room temperature by leaving your homemade thermometer in the room.

Feeling a bit warm? Try these 6 Smart Ways to Circulate Air (in a room with only one window).

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