What is static shock?

The static electricity that causes a shock is not the ordinary “current electricity” which runs through wires and power our home appliances. Static electricity is an unbalance between the number of charges within or on the surface of any object or body. The reason behind this unbalance is that when intentionally or unintentionally two objects are rubbed together or make close contact, one of these objects become abundant in positive charges by giving up an electron and the other one gets excess of negative charges by taking up the electrons and filling the vacancies available in the outer shell [1] [2]. As shown in the diagram below.

They grey part can be termed as the carpet while the black one as an object. It takes electrons to have a higher negative charge and leaves the carpet with a higher positive charge.

A very common phenomenon is the rubbing of our feet on the carpet which gives us a negative charge and when we open the nearest door using the knob, we experience a slight shock which is the result of electrons jumping from knob to our body. There are many other examples in our daily life [2].

Situations which can lead to a static shock include:

Touching a microwave

Although microwaves using current/ electricity to work, you can experience a very heavy shock if it’s not grounded properly or the circuitry is naked without any covering near the LED panel because the microwave is working on 240V and can cause serious injuries. However, this is only the case of electric shock and not static shock. Microwave can be a good reason for a static shock as well. The body of microwave is also a metal, so whenever you move through your TV lounge to the kitchen to grab something from the microwave you can get a slight itch known as the static shock. This is due to your movement over the carpet, from where you can get an excess of electrons, and upon touching the microwave you are transferring those electrons to the oven. Next time, whenever you crave a midnight snack and reach for the microwave, you need to keep that phenomenon in mind and prevent yourself.

Washing your hair

Especially in winters, our hairs rise in some situations depicting that we have either got a strong electric current in them or its due to an expensive hair gel. Well, the actual phenomenon is not as it seems. This rise in our hairs is also due to a static shock that is built up due to a cap or hat on our head for too long, so unbalance of charges has occurred between them. When we take off our hat, our hairs have got excess of negative charge by taking electrons from the hat. Each hair tries to repel the nearest one by staying away and rising as all of them contain the same negative charge [3].

Contact with a fridge, computer, car door, or other metal appliances

As described earlier, rubbing two objects together gives rise to the unbalance of charges within or on the surface of those objects. So whenever, you rub your shoe or feet across the floors either carpeted or consisting of nylon matting in your houses you are prone to get a static shock in the next few minutes. It’s not particularly your feet it can be your hands or other body parts too, but feet are more likely to come in contact with charged bodies. You will get a positive charge or negative charge upon this contact and the next immediate object you touch if it is

metal is very likely to target that abundant charge in your body consequently giving you a little shock. The most common ones include your door’ knob, your computer or PC having open wires, the fridge in the kitchen, and yes it can be your car’s handle too [4].

Is lightning an example of static electricity?

Lightning during rain or storms is a very common and solid example of static electricity in nature. The shock we experience in our homes is an infinitesimally small amount of shock or spark produced by the lightning bolt. The turbulences in the clouds caused by the rain or thunderstorm produces charges that build up so high until they are shifted from one cloud to another or are shifted to any object on the ground. While the slight static shocks experienced in the household are nothing compared to lightning as the temperature is 27,000 degrees Celsius and it is almost six times greater than the surface of the sun [6].

Why static shock is frequently experienced in winters as opposed  to summers

Have you ever thought, the little shocks you get through static electricity are more frequent in winters than summers and almost everything in the house is giving you a slight Zap?

Yes, the phenomenon is true, winters have got something for the static electricity which summers do not offer. Winters are more dried up having less moisture in the atmosphere. Although we use humidifiers and other heaters to level up the humidity in the air but still summers are more moisturizing. In winters, we scratch our feet on the carpet more to get some heat and this increases the odds of getting the shock. Moreover, the moisture in summers can dissipate those extra electrons we carry either through our shoes or feet and on other metals. The dry air leads to more clinging of electrons or charges leading to a shock!

Few other daily life examples of static shocks include [4]:

• Rubbing the snow with our bikes or skis in winters
• Interacting with furry animals 
• Putting on Sweaters in winters
• While printing papers through a photocopier
• Cleaning and waxing a car
• Dry cleaning or wiping the glass window
• Rubbing balloons on the neck
• Flying through dust, air, snow, or rain
• Turning pages in a book.

All above-mentioned situations are associated with changing humidity, temperature, and conditions. The below table shows the amount of electrostatic discharge or the Static current generated and the RH (Relative humidity) values in the atmosphere.

Preventing static shocks:

It must be irritating and exhausting in winters to be always on the verge of getting a static shock from almost everything around. You must hesitate whenever you are going for a door’s knob or a car’s handle, wearing a sweater, or petting your cat.
We have also some cure for this irritation. Few of the easy preventions from these types of static shocks are listed below:

Prevention from metal objects

Nowadays, our household is full of electrical and digital appliances and all of them feature either a metal handle or an outer opening which is made up of any type of metal. These are the worst things in terms of getting a shock. A very easy method is to keep yourself intact with a metal object. Keep touching your bare hand on something inside the car which is made of metal so when you get outside you will not be getting any sudden shock from the car door’s handle. This is an easy trick in case of metals to constantly remain in touch with them to avoid the accumulation of excess of charges [5].

Prevention from clothing and carpet

Nylon carpets are also one of the common reasons which give up an electron to your feet or shoes you are wearing. To avoid them, get rid of any shoes having rubber sole or socks made up of wool or nylon. Try wearing leather shoes or cotton socks which will minimize the electrostatic effect produced through rubbing on the carpet. In winters, the furniture fabric is also a main reason behind the static current, so you need to avoid any woollen or nylon accessories by covering them with cotton covers to get rid of this jerk.

Moreover, wearing and taking off sweaters also give a slight current in the body which is made of wool or other friendly material prone to electrostatic current. If you switch your clothing to cotton stuff, not only it will avoid static shocks but also it will be more comfortable to roam and sit around in the house with cotton clothing [9].

Prevention during outdoor activities especially from shopping carts in a store

You always build up a charge when you walk around while its quantity and intensity may vary and can or cannot lead to a shock. When you are walking outside especially in a grocery store holding a trolley or shopping cart you may experience the shock more often because the wheels of the trolley also get excess of charge by constantly rubbing through the floor and you get a jerk or current when you reach for an item in the cabinet or touch any railing. To avoid this, try wearing leather shoes whenever you roam outside or go for shopping. Another prevention is to hold a key chain or a key in your hand every time and keep touching it to nearby stairs, railings, and cabinet to get rid of charge before you feel the shock from this charge. This touching of metal will transfer the excessive electrons and will keep you safe.

Prevention during the winter season

Apart from wearing leather-soled shoes and cotton clothing can help reduce the static current up to a certain level. To maximize the prevention and further decrease any chances of building up of static charges in the home during winters, you need to increase the humidity level. As the dry air increases the chances for the current, so you need to target that dried air for the prevention. Certain types of devices called the humidifiers can be used to increase the humidity percentage in the air normally it can be kept from 30 to 40% making it comparable to the summer season as moisture diminishes the charges produced or accumulated [6]. The specific devices for this phenomenon are described later in this article. The below graph shows the relation of humidity versus the static charge produced in the human body.

 Prevention from light switches

Different light switches have metal bolts to stick to the wall and most of the people also get a jolt when turning any appliance on/off from these switches. To avoid any shocks from these switches or the bolts associated with their board, you need to make sure you are not wearing any wool or synthetic clothing, also your shoes should be leather ones. Apart from that use a hand moisturizer every time when you are using your hands on something made of metal. Moisturizers will also keep your skin fresh and smooth and at the same time, they will help you avoid any type of static shocks as water resist accumulating of charges. The products such as moisturizers are also described later in the article. Moreover, wipe the switches with dryer sheets made up of cotton material which will minimize the electrostatic effect [11].

Prevention of static shock from pets, especially cats and dogs

Whenever the humidity level falls below 30% in the air, the chances of shock increase and you cannot play with your pet’s fur. Because it will result in a sudden jolt for you and your pet too whether it’s a dog, cat, or any other animal with excessive fur to give rise to electrostatic current. People may use certain humidifiers for this purpose, but a very good option is to go for moisturizers which can help keep the body and fur moist. You can buy any good lotion, sprays, or moisturizer which is free from any harmful effects and apply it on your pet’s fur and then slightly brush through all its hairs making them less dried. You can also use certainly soaked rags that will keep their fur little moist and free from any static shocks. Brushing your pet’s fur with natural ingredients including oil and lotions is also a viable measure to cope up with their dryness for medical reasons [12]. 

Different types of cotton rugs and sheets can also be opted for other home appliances not only for prevention from static current but also for cleaning purposes which is a good substitute to synthetic wipes used.

Different products for prevention of static shocks:

Most people are unaware of the various ways to prevent themselves from static shock. Furthermore, there are provisions, rules, and regulations from the authorities to care for workers and provide necessary products in order to avoid any type of shocks in the workplace. Below is an image showing different anti-shock products for a typical factory worker:

Have you ever thought of using conductors in your body and clothing to avoid these shocks?

When you become aware of the fact that insulators keep the charge in the body which later results in a static shock, the first thing that would come to mind is;  can I use some copper wire (or some conductive material) to transfer all the charges to the ground? Well, yes, it can be done to some extent. A few researchers have presented the idea of attaching some copper wire to the chassis of a car and letting it drag along the ground in order to discharge the build-up of charges.

Although the experiments were not commercially adopted the principle has been applied to many other items. The same experiment was done for a shoe containing an anti-static car strip in the shoe sole.