Why Don’t Hair Dryers Have An Earth Wire? (Explained)

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An earth wire is a common feature in a lot of electric appliances. By providing a path for electric current flow, earth wire can protect users from electric shock and prevent these electrical appliances from being damaged in case a fault happens.

Hair dryers do not have an earth wire because they do not need one.

Here is Why Hair Dryers Do not Need an Earth Wire:

Electric devices enclosed in a plastic case or shell, such as hair dryers, do not need an earth wire. This is because these electric devices are designed to have two levels of insulation between the electrical components of the device and any external parts that can be touched.

What Is An Earth Wire?

You may have heard of earth wire, which is common in many electric appliances.

An earth wire is a wire that connects an appliance to the earth. A wire provides an electrical connection from the appliance to the ground.

Electric appliances have a main electric supply with three wires: the earth, the neutral, and the live wire. They are color-coded to ensure that they are connected properly and would not be mixed up.

The earth wire is green with a yellow stripe, the neutral wire is blue, and the live wire is brown.

The earth wire is copper, coated in striped green and yellow plastic. This wire provides a path that allows the current to flow from the device to the ground if there is an electrical fault. ‘

Without the earth wire, there is a serious safety hazard if an electrical fault occurs and the live wire becomes loose inside the appliance. The next person who will use the appliance can get electrocuted and injured.

The earth wire is connected to the main electric supply and is attached to a metal plate underground. Because the wire is made of copper, the earth wire makes for a low resistance path going into the ground.

If an electrical fault happens, the live current passing through will follow this path to the ground instead of passing through a person using the appliance. Then it will blow a fuse to prevent the appliance from being damaged.

Appliances such as refrigerators, washing machines, and electric stoves have an earth wire. An earth wire is necessary for appliances with metal casings.

Some appliances and small devices, such as hair dryers, hand whisks, and vacuum cleaners, do not have an earth wire. This is because they have plastic casings that are great insulators.

Plastic casings do not conduct electricity, so they cannot give an electric shock even if the electrical components inside become loose.

Why Don’t All Hair Dryers Use Earth Wires?

Hair dryers do not use earth wires because they have an exterior casing or shell made from plastic. Plastic is known as a very good insulating material.

Generally, an electric device or appliance with a plastic casing will not need an earth wire. This is because plastic is a very good insulator. It does not allow electric currents to pass through.

Hair dryers have two levels of insulation between the electrical components and the external plastic casing that prevents the user from getting electrocuted while protecting the device from damage.

Even if an electrical fault occurs inside the hair dryer, it still will not electrocute the user as electric currents will not pass through from the main power supply to the external plastic casing.

Should Hair Dryers Be Earthed?

Some electrical appliances and devices must be earthed because they can cause an electric shock if a fault occurs.

These appliances usually have metal casings, which are conductors.

Hair dryers have plastic casings, and plastic is known to be a very good insulator. If a fault occurs, electric currents will not pass through the electric casing, so it will not electrocute the user.

Therefore, hair dryers should not be earthed.

Can You Earth A Hair Dryer?

Since hair dryers do not need to be earthed, it does not have any components you would need to connect an earth wire.

Simply put, you cannot earth a hair dryer.

This is completely fine since hair dryers have their safety features. Also, the plastic casing that it comes with can effectively prevent electric shock, rendering an earth wire useless.

What Hair Dryer Models Are Grounded?

While most hair dryers for home use have plastic casings and are not grounded, some hair dryers have an earth wire and are grounded.

Hooded or standing salon hair dryers and hand-held hair dryers with external metal components are grounded. This is because their metal casing conducts electric currents, which can electrocute the user if a fault occurs.

Here are some standing or hooded hair dryer models that are grounded:

Some hand-held hair dryers can also be grounded when they have metal casings.

Here are some hand-held hair dryers that are grounded:

Can You Be Shocked by a Hair Dryer?

Hair dryers generally have safety features that can prevent you from getting an electric shock while using the device.

One of these safety features is the plastic casing which eliminates the need for an earth wire, as the casing can prevent you from getting an electric shock.

Other safety features of a hair dryer include the following:

  • Front Grill – This safety feature prevents the user from contacting the device’s internal heating and electrical components.
  • Protective Screen – This safety feature acts as a barrier to prevent lint from building inside the device and, in turn, prevent the device from overheating.
  • Insulation – This is the feature of the hair dryer that prevents its body from getting too hot. This includes the plastic casing.
  • Thermal Fuse – This safety feature further protects from overheating and possibly catching fire by breaking the circuit at an abnormally high temperature.
  • Bimetallic Strip – This feature trips a switch that cuts off the power, so the hair dryer stops working when the temperature gets too hot.
  • Safety Cut-Off Switch – This safety feature trips the circuit and shuts off the motor when the temperature exceeds 60 degrees Celsius or 140 degrees Fahrenheit.

Since a hair dryer has these safety features, it is highly unlikely to shock you as long as it is used normally.

However, if the hair dryer gets wet, and you plug it while it is wet, it can shock you. The same goes for using your hair dryer while your hands are wet.

This is why you always have to ensure that your hands are dry when using the hair dryer. This is also why it is strictly prescribed not to use your hair dryer in the tub.

Also, if the hair dryer has faulty wires or the electric cord has tears and holes, it can shock you if you try to plug it. You must regularly check the electric cord for any damages or faults.

Sources:

Domestic Electricity And Mains Electricity

What Is The Function Of An Earth Wire? Why Is It Necessary To Earth Metallic Appliances?

Hairdryers And Electrocution: Real Threat Or Hollywood Hype?

Product Safety: Hair Dryers