The basic method of making anti-static requirements for electronics factories
First, the basic principles of electrostatic protection
a, inhibit the accumulation of static charge;
b. Quickly, safely and effectively eliminate the static charge that has been generated.
Second, anti-static work area venue
1. Ground material
a. It is forbidden to directly use wooden floors or lay wool, linen, chemical fiber carpets and ordinary floor leather.
b. The ground made of electrostatic conductor material, such as anti-static raised floor or anti-static mat on ordinary ground, should be selected and effectively grounded.
c. It is allowed to use specially treated terrazzo floor, such as laying ground wire, carburizing or spraying antistatic agent on the ground.
2, ground
a. The anti-static system must have an independent and reliable grounding device. The grounding resistance should be less than 10Ω. The embedding and testing methods should meet the requirements of GBJ 97.
b. The anti-static ground wire shall not be connected to the power supply neutral line and shall not be shared with the lightning protection ground wire.
c. Use three-phase five-wire system to supply power, and its ground wire can be used as anti-static ground wire (but the neutral wire and ground wire must not be mixed).
d. The cross-sectional area of the grounding main line shall not be less than 100mm2; the cross-sectional area of the trunk line shall be not less than 6mm2; the grounding line of equipment and workbench shall be a multi-strand plastic coated wire with a cross-sectional area of not less than 1.25mm2, and the color of the grounding wire shall be yellow-green It is appropriate.
e. The connection method of the grounding main line should be brazed.
f. Anti-static equipment connection terminals should ensure reliable contact, easy to install and disassemble, and allow the use of various clip-on connectors, such as squid clips and plug sockets.
3, ceiling material
Ceiling materials should be made of antistatic materials. Under normal circumstances, gypsum board products are allowed, and ordinary plastic products are prohibited.
4, wall fabric
Anti-static wallpaper should be used for wall fabrics. Gypsum paint or lime paint wall is generally allowed. It is forbidden to use ordinary wallpaper and plastic wallpaper.
5, humidity control
a. The relative humidity of the anti-static working area should be no less than 50%.
b. Allow the use of humidification equipment to spray the preparation or water to increase the ambient humidity without adversely affecting the product.
c. The humidity of the computer room should comply with the relevant regulations in GB 2887, and similar computer rooms should also comply with this regulation.
6, regional boundaries
The anti-static work area shall indicate the boundary of the area, and the warning signs shall be hoisted at obvious places. The warning signs shall comply with the provisions of GJB1649, and the ionized air air bath equipment shall be arranged at the entrance of the work area.
7, charge source
It is forbidden to use and contact the charge source that is easy to generate static charge in the anti-static work area (see below).
Charge source:
Workbench surface, painted or varnished surface, plain plastic veneer, ordinary vinyl and resin surface
Plastic and ordinary floor leather, polished waxed wood flooring. Ordinary vinyl overalls, caps, shoes
Ordinary polyester, synthetic fiber and nylon fabrics, plastic and ordinary rubber soles operating tools and equipment
Ordinary plastic boxes, racks, bottles, trays and paper products, ordinary foam and general moving tools, compressors, spraying equipment, evaporation equipment, etc.
Third, electronic products anti-static facilities
1. Static safety workbench
a. The electrostatic safety workbench is an essential part of the anti-static work area. It consists of a workbench, an anti-static table mat, a wristband joint, and a grounding wire.
b. There should be no less than two wristband connectors on the anti-static table mat, one for the operator and the other for the technician, the inspector or other personnel.
c. If necessary, the electrostatic safety workbench should be equipped with an ion wind static eliminator.
d. It is not allowed to stack plastic boxes (sheets), rubber, cardboard, glass and other debris that are easy to generate static electricity on the static safety workbench. The drawings and materials should be placed in the anti-static paper bag.
2, anti-static wrist strap
Persons who are in direct contact with electrostatic sensitive devices should wear anti-static wristbands. The wristbands should have good contact with human skin. The wristbands must be non-irritating and non-allergic to the human body. The resistance of the wristband system should be in the range of 106-108 Ω. Inside.
3, anti-static container
In the development and production of electronic equipment, all storage and turnover SSD containers (component bags, transfer boxes, printed boards, component storage boxes, etc.) should have electrostatic protection. Metal and ordinary plastic containers are not allowed. If necessary, the tote box for the storage unit should be grounded.
4, ion wind static eliminator
An ion wind static eliminator should be used to eliminate the static charge on the surface of the insulating material.
5, anti-static overalls
a. Persons entering the anti-static work area or contacting the SSD should wear anti-static overalls. The anti-static overalls fabrics should meet the requirements of GB 12014.
b. In an environment with a relative humidity greater than 50%, the anti-static overalls are allowed to use pure cotton products.
6, anti-static work shoes
Persons entering the anti-static work area or contacting the SSD should wear anti-static work shoes. The anti-static work shoes should comply with the relevant provisions of GB4385. Normal shoes are generally allowed, but a conductive shoe bundle or heel strap should be used at the same time.
7, anti-static transport vehicle