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Only ESDP hand tools should be used in the EPA. Manufacturer recommendations for usage and cleaning shall be followed. Component holding trays, microscopes, and other devices or fixtures commonly found in an EPA shall be constructed of metal or permanent static dissipative plastic and shall be maintained at ground potential by placing them on a grounded tabletop while in service at the workstation.

A good practice is to have the technician always touch the metal portion of a tool when picking it up. This practice will assure that any charged metal in the tool will discharge through the technician’s wrist strap to ground.

Soldering Equipment

Soldering iron and desoldering/rework system tips shall be grounded. The resistance between the tool’s tip and its ground shall not exceed 10 ohms. All soldering iron tip grounds in an EPA shall be periodically verified. The test methodology is found in ESD DS13.1 “ESD Association Standard Test Method for Measuring Electrical Potential from Soldering/Desoldering Hand Tools”.

Desoldering Equipment

Only ESD-protective desoldering equipment shall be used when working on ESD sensitive hardware. Only antistatic solder suckers made from metal or having at least a metallized plastic barrel and dissipative tip shall be used in an EPA.

Common Ground at the Workstation

All tools, equipment, or fixtures (such as lead forming tools, test fixtures, lights and solder pots, etc.) that are too large to be placed on the protective work surface shall be connected to the common ground point.

 

Conductive floors or grounded conductive floor mats are mandatory in any EPA where personnel handling ESDS items are not wearing wrist straps. Under these circumstances, personnel shall use leg straps, heel straps, or conductive shoes.

ESDP flooring or floor mats shall be used in all Class 1 facilities.

The proper cleaning and maintenance of a conductive floor is of extreme importance since the use of normal floor wax on conductive floors or floor mats can defeat their effectiveness. Personnel cleaning these items shall use the manufacturer approved cleaning agents and cleaning recommendations as minimum requirements. With guidance from the ET&V Officer, the Facility ESD Monitor will determine the cleaning regimen for the flooring and mats if the manufacturer’s recommendations are not acceptable.

Conductive/dissipative floors or grounded conductive/dissipative floor mats shall have a maximum resistance to ground of 1×109 ohms and a minimum resistance of 1×105 ohms. The test methodology for flooring is found in ESD S7.1 “ESD Association Standard Test Method for the Protection of ESDS Items – Resistive Characteristics of Materials – Floor Materials”.

Standard carpeting shall not be used in an EPA. Even the use of ESDP carpet woven with conductive fibers, which have previously been approved for use at JSC, can still be very problematic. If the conductive fibers are not dense enough, the resistance to ground will increase as the carpet wears. The selection of carpet in an EPA environment shall require pre-installation approval of the ET&V Officer.