What is Static Electricity?, How it is creates?, What Are the Hazards of Static Electricity? and How Can Static Electricity Be Controlled?

What is Static Electricity?
Static electricity is the imbalance of positive and negative charges.

  • Why does your hair stand up after you take your hat off?
  • If you walk across a carpet, electrons move from the rug to you. Now you have extra electrons. Touch a door knob and ZAP! The electrons move from you to the knob. You get a shock.
How it is creates?

  • It is created when two objects or materials that have been in contact with each other (or) separated.
  • The generated charges don’t have a path to the ground, they are unable to move and become “static”.
Why don’t we always get static charge build-up?

  • if charge moves away faster than it is generated, then no problem
  • if charge is generated faster than it can move away then build-up occurs
  • High voltages quickly arise
Static electricity is commonly produced when:

  • Liquid flows through a pipe or hose, or though an opening in a pipe or hose
  • Spraying, coating, Blending, Mixing
  • Filling tanks, drums, cans or pails
  • Dry powdered material passes through chutes or pneumatic conveyors
What Are the Hazards of Static Electricity?

  • The main hazard of static electricity is the creation of sparks in an explosive or flammable atmosphere.
  • Sparks can set off an explosion or fire.
  • The danger is greatest when flammable liquids are being poured or transferred.
How Can Static Electricity Be Controlled?
Some ways to prevent static charges from accumulating on materials are:

  • Bonding and Grounding: Bonding and grounding are common controls for static electricity.
  • BondingConnecting two or more conductive objects with a conductor, such as a copper wire, that equalizes the potential charge between them.
  • Grounding: Connecting one or more conductive objects directly to the earth using ground rods.
  • Humidification: A relative humidity of 60% to 70% at 21°C (70°F) may prevent static electricity problems. However, there is no guarantee against the accumulation of static electricity. Therefore, don’t rely solely on humidification as a control measure in areas where there are flammable liquids, gases, or dusts.
  • Static collectors: Devices that collect static electricity can be used on moving belts, plastic film, and similar non conductive materials. Some examples of static collectors include: Needle pointed copper combs, Spring copper brushes and Metallic tinsel bars.
  • Additives: Another control is the use of anti-static additives (as in fuels). 
  1. The additive increases the conductivity or lowers the resistance of the liquid.
  2. It also reduces the time it takes for the static charge to leak through the wall of the container and to the ground.

  • Controlling static electricity on people
The human body is a conductor and may need to be grounded

  1. Conductive flooring
  2. Conductive clothing and footwear
  3. Touch Pads at Every Entrance of The Work Place,
  4. Wrist Bands, 
  5. Heal Strips, 

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