The workspace should be situated away from carpeted areas because carpets can cause the build up of electrostatic charges. If distance from carpeting is not possible, the carpeted surface could be covered with a plastic anti-static mat such as those commonly used under desk chairs. Using ESD protection tools such as a wrist strap and a mat, which are commonly sold in kits, can largely eliminate this type of danger. The wrist strap is usually clipped to the metal system chassis on which the work is being done, providing ground to prevent ESD damage. The mat is usually laid on the workspace next to or under the system case. The mat is then clipped to the case to provide a grounded surface on which parts can be placed as they are removed from the system. After putting the wrist strap on, allow 15 seconds to pass before touching any sensitive electronic components with bare hands. This pause allows the wrist strap to neutralize the static electricity that already exists on a person's body. ESD potential can also be reduced by not wearing clothing made of silk, polyester, or wool. These fabrics tend to build static charges. Avoid other man-made items, such as cotton, leather shoes, and so on, which can cause static electricity. A wrist strap can only offer protection from ESD voltages carried on the body. ESD charges on clothing can still cause damage. Therefore, avoid making contact between electronic components and clothing. If static shocks are still being experienced in the workspace while working near a computer, try using a fabric softener or using an anti-static spray on clothing. Be certain to spray clothes and not the computer. A wrist-grounding strap does not discharge electrostatic charges that have built up on hair, so take precautions to ensure that hair does not rub across any of the components. Electronic components or circuit boards should be stored in shielded anti-static bags, which are easily recognized by a shielding characteristic. This usually has a silvery-sheen, transparent appearance. Shielded anti-static bags are important because they prevent static electricity from entering the bags. Shielded anti-static bags need to be in good condition, without crinkles or holes. Even tiny openings from crinkles will limit the ability of the bag to provide protection from electrostatic discharges. When original packaging is not available, circuit boards and peripherals should be transported in a shielded anti-static bag. However, never put a shielded anti-static bag inside a PC. In addition, never plug in a motherboard while it is sitting on top of an anti-static bag. Remember that anti-static bags are anti-static because they are partially conductive. A motherboard could easily be shorted out while starting up if several hundred pins from its components were touching the conductive bag. If computer components are stored in plastic bins, the bins should be made of a conductive plastic. A non-conductive plastic bin will tend to build up an electrostatic charge. Make a habit of touching the bins to equalize the bin charge to the body before reaching for the components in the bin. When passing components between individuals, first touch the skin of the hands before passing the component. Handle all components by their edges. Avoiding touching pins, chips, or anything else made of metal, so that the chance of producing a damaging electrostatic discharge will be reduced. Reducing the potential for electrostatic discharge reduces the likelihood of damage to delicate circuits or components. Avoid touching the computer screen for any reason while it is turned on. Even brief touches to an active screen can put an electrostatic charge in the hand that can discharge through the keyboard.
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