TM-9-1290-365-24&P Technical and Parts Manual for Paladin Muzzle Velocity System M93 Upgraded Download
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ARMY TM 9-1290-365-24&P 1.5 SAFETY, CARE, AND HANDLING. 1.5.1 Electrostatic Discharge (ESD) Awareness. It is essential to understand the nature of electrostatic discharge (ESD), what causes it, and the problems it can cause. This paragraph contains information on the areas of major concern. 1.5.2 Typical Prime Charge Sources. Means of generating electrostatic charges (voltage) and their relationship to relative humidity are shown in Table 1-2. Table 1-2. Means of Static Charge Generation Means of Static Generation Electrostatic Voltages- 10-20 Percent Relative Humidity Electrostatic Voltages- 65-90 Percent Relative Humidity Walking across carpet 35,000 1,500 Walking on vinyl floor 12,000 250 Worker at workbench 6,000 100 Vinyl envelopes for work instructions 7,000 600 Common poly bag picked up from bench 20,000 1,200 Work chair padded with polyurethane foam 18,000 1,500 1.5.3 Prime Charge Carriers. Personnel are the prime charge carriers with the greatest potential of damaging ESD items. Activities such as walking, working at a table or bench, sliding on a chair, or simply combing one's hair can generate static charges of thousands of volts with high potential for damage to sensitive devices. 1.5.4 Items to Avoid. The following items will generate sufficient charges to damage sensitive items: all common plastics, spray cans, tape dispensers, heating guns, bubble packs, polystyrene cups, cigarette papers and wrappers, paint cans, stencil ink applicators, common poly bags and sheets, and plastic tape. 1.5.5 Handling Unpackaged ESD Sensitive Items. Never store or transport ESD sensitive components or assemblies outside of the protective packaging. The protective packaging should not be opened or removed until the item is to be installed in the next higher assembly. At this time, the technician should be grounded in an approved workstation. Avoid touching bare leads and contacts on sensitive material. Never use plastic solder suckers to remove soldered components from ESD sensitive assemblies. Use metallic or antistatic solder removal means. 1.5.6 Packaging and Labeling ESD Sensitive Items/Assemblies. After replacement of a sensitive circuit card assembly (CCA) or other subassembly into an instrument, the CCA that is to be returned for repair must be repackaged in ESD protective material to prevent further damage Mom handling and transit. For field returns, antistatic ziplock bags are available for CCAs and other small assemblies. The container with the ESD sensitive material warning label should also be used for returning defective material to ensure proper handling during shipment. 1-5