There are a number of devices that can be used for measuring pressure. A barometer is used for tracking changes in air pressure. Water pressure in a home or other structure is measured by using a special gauge that is designed specifically for this purpose.
The word barometer is derived from two Greek words meaning "weight" and "measure." This device for measuring pressure was invented in 1643 by Evangelista Torricelli. The barometer is made with a glass tube that is placed into a container of mercury. To work properly, the glass tube must be emptied of all air.
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The air surrounding the container of mercury pushes down on it. As a result of the fact that the glass tube is a vacuum, the mercury is pushed up into the tube. Measuring pressure in the air is a simple matter of reading the number of inches of mercury that are displaced when the level changes.
This method of measuring pressure can be used with other liquids instead of mercury. Water is a common liquid that can be used for this purpose. Since mercury is more dense than water, it is the liquid that is usually used in barometers.
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Water pressure can be measured in a house or any other type of structure by using a gauge. To find one, visit a local hardware or building supply retailer. To get a reading for the static water pressure in a building, the first step in the process is to shut off all of the water in the structure. Once all the faucets and other sources of water in the building have been shut off, the next step in measuring pressure is to attach the water gauge a connection where water is entering the building. If you are trying to measure the water pressure in your home, the cold water connector for the washing machine is a good choice.
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Once the water gauge has been connected, turn on the water and let it enter the gauge. Take a reading after the water has entered the gauge to find the static water pressure for the structure. After you have made a note of the number, the process is complete and you can disconnect the gauge. Be sure to shut off the water first.
To find out what level you should be looking for when measuring pressure, look to the local water company for help. Contact them to ask what the static pressure should be for the area where the building is located. Some companies will give a range of acceptable water pressure readings. When measuring pressure for water inside a building, the number on the gauge may refer to Pounds per Square Inch, or PSI. This unit of measurement is used in the United States and the United Kingdom.