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NAVSEA SE 003-AA-TRN-OOLEYE VELECTROSTATIC DISCHARGETRAINING MANUALDTICs,T OFI!ELECTE,,4MA9 9810W\REPUBLISHED BY DIRECTION OFCOMMANDER, NAVAL SEA SYSTEMS COMMANDAl,:,,; . release,Diribun Unlimit d81 12,3 066
Ai/') NAVSEA-SE-p23-AA-TRN-010:6.ELECTROSTATIC DISCHARGE.TRAINING V4ANUAL.PUBLISHED BY DIRECTION OFCOMMANDER, NAVAL SEA SYSTEMS COMMAND------- --SEP.80
FOREWORDMANY ELECTRONIC PARTS SUCH AS MICROCIRCUITS, DISCRETE SEMICONDUCTORS,FILM RESISTORS AND CRYSTALS ARE SUSCEPTIBLE TO DAMAGE FROM ELECTROSTATIC DISCHARGE (ESD).COMPREHENSIVE ESD CONTROL PROGRAMS ARE REQUIRED TO PROTECT THESEPARTS DURING MANUFACTURE, ASSEMBLY, TEST, REPAIR/REWORK, MAINTENANCE, AND OTHERHANDLING OPERATIONS.SUCH CONTROL PROGRAMS MUST BE IMPLEMENTED THROUGHOUT THETHE INTENT OF THIS TRAINING MANUAL ISLIFE CYCLE OF THESE ELECTRONIC PARTS.TO COMPLEMENT AN ESD AWARENESS TRAINING COURSE WHICH IS A KEY PART OF ANY EFFECTIVE ESD CONTROL PROGRAM.PRINCIPLES OF STATIC ELECTRIC'ITY,THIS MANUAL COVERS TOPICS SUCH AS:CHARGING AND DISCHARGING, PRIME STATIC GENERATORS, STATIC ELECTRIFICATION OFELECTRICAL AND ELECTRONIC PARTS, ELEMENTS OF AN ESD CONTROL PROGRAM, ESD PROTECTIVE MATERIALS, ESD PROTECTIVE EQUIPMENT, PACKAGING AND MARKING OF ESDS ITEMS,ESD IN DESIGN, ESD HANDLING PRECAUTIONS AND PROCEDURES, AND MONITORING OF ESDCONTROL PROGRAMS. -C-NDING OFFICERUBLICATIONS AND FORMS CENTERNAVA5801 TR AV U, PENNSPHILADELPREVAN191ESTS FROM INDUSTRY SHOULD BE FORWARDEDU.S. GOVER METHE SA EREPRESENTDDRESS, ATTN:VE.G., DE SAMESA) OR MARS VIA TPURCHALOCAIRECTLY FROMODE FOIG. -ANAVAL SEA SYSTEMS COMMANDDEPARTMENT OF THE NAVYCODE 6151WASHINGTON, D.C. 20362,--.2SEPTEMBER 1980', ,,, p
i1.TABLE OF CONTENTSPageI.II.III.IV.V.INTRODUCTION .1A. BACKGROUND .1B. ESDS PART FAILURE .1C. TRANSIENT UPSET FAILURE .2D. TRANSMITTED FAILURES .3E. THE ESD PROBLEM .3F. ESTABLISHED ESD CONTROL PROGRAM REQUIREMENTS .3PRINCIPLES OF STATIC ELECTRICITY .10A. BACKGROUND .10B. TRIBOELECTRIC EFFECT .10C. MATHEMATICAL FORMULATION OF ELECTROSTATIC FIELDANALYSIS .13CHARGING AND DISCHARGING .30A. INTRODUCTION .30B. PARAMETERS INFLUENCING THE MAGNITUDE OF STATIC CHARGEGENERATION .42C. MATHEMATICAL EXPRESSIONS FOR ELECTROSTATIC DISCHARGE .43PRIME STATIC GENERATORS .51A. TYPICAL CHARGE GENERATORS .51B. MANUFACTURING PROCESSES GENERATING STATIC ELECTRICITY .51STATIC ELECTRIFICATION OF ELECTRICAL AND ELECTRONIC PARTS .55A. GENERAL .57B. FAILURE MECHANISMS .57C. LATENT/DEGRADATION DAMAGE FAILURE MECHANISMS .61D. EXAMPLES OF ESD FAILURES .61
i1.TABLE OF CONTENTS (Cont'djPageVI.VII.ESD CONTROL PROGRAM .71A. GENERAL .71B. PROGRAM REQUIREMENTS .71C. TAILORING .81ESD PROTECTIVE MATERIALS .84A. GENERAL .84B. ESD PROTECTIVE MATERIALS .84C. ELEMENTS OF AN ESD PROTECTED AREA . lo0VIII.ESD PROTECTIVE EQUIPMENT . 121A. GENERAL . 121B. IONIZERS . 121C. ESD PROTECTIVE TOOLS . 123D. ELECTROSTATIC DETECTORS AND ALARMS . 124E. PORTABLE ESD WORK STATION KITS . 126F. SPECIAL ESD TEST EQUIPMENT . 126IX.PACKAGING AND MARKING OF ESDS ITEMS . 128A. GENERAL . 128B. PROTECTION AGAINST TRIBOELECTRIC GENERATION . 129C. PROTECTION AGAINST DIRECT DISCHARGE . 129D. PROTECTION AGAINST ELECTROSTATIC FIELDS . 129E. SHUNTING DEVICES . 130F. NAVY ESD PACKING REQUIREMENTS . 130G. REPACKAGING FOR DISTRIBUTION . 131
TABLE OF CONTENTS (Cont'i)PageX.ESD IN DESIGN . 132A. GENERAL . 132B. HUMAN MODEL EQUIVALENT CIRCUIT .133C. ELECTROSTATIC DISCHARGE TESTING. 136D. EXAMPLES OF SOME TYPICAL DAMAGE PATH IN MICROCIRCUITS . 148E. COMMENTS ON EMP TESTING AND CONVERSION OF EMP DATATO ESD. . 150F. ESO PROTECTIVE CIRCUITRY .159XI.ESD HANDLING PRECAUTIONS AND PROCEDURES . 186A. GENERAL HANDLING PRECAUTIONS .186XII.MONITORING OF ESD CONTROL PROGRAMS. 190A. GENERAL . 190B. ESD PROGRAM MONITORING AND AUDITS. 190C. FORMAL REVIEWS. 201XIII.REFERENCES . 204SEEM-
ELECTROSTATIC DISCHARGE (ESD)CONTROL PROGRAM TRAINING COURSEI.INTRODUCTIONA. BACKGROUNDSTATIC ELECTRICITY IS FAMILIAR TO US ALL AS LIGHTNING, STATICCLING OF CLOTHING AND SPARKING WHEN TOUCHING A DOOR KNOB OR OTHER METALLICOBJECTS IN COOL, DRY WEATHER.ORDINARY VINYL CLEAN ROOM DRAPERIES CAUSED CONSIDERABLEINTERFERENCE WITH THE MARINER SPACECRAFT RECEIVERS AT JET PROPULSION LABORATORIES IN PASADENA, WHENEVER A PASSING TECHNICIAN BRUSHED HIS BUNNY-SUITAGAINST THE CLEAR VINYL CURTAIN WHICH FORMED THE WALLS OF THE PORTABLEDOWN-FLOW ROOM IN WHICH THE MARINER WAS ASSEMBLED.STATIC ELECTRICITY AND THE DIRT IT ATTRACTS CAN CAUSE DATALOSS IN A COMPUTER.BOTH ARE RESPONSIBLE FOR MAJOR PROBLEMS SUCH ASPRINTER MALFUNCTION, PAPER JAMS, DESTRUCTION OF SENSITIVE LOGIC CIRCUITSAND THE ATTRACTION OF CONTAMINANTS TO READ/WRITE HEADS AND MAGNETIC RECORDING SURFACES.ADDITIONALLY, STATIC CAN PRODUCE NOISE TRANSIENTS INSYSTEM INTERFACE LINES CAUSING EQUIPMENT MALFUNCTION OR DEGRADATION OFSYSTEM PERFORMANCE.FOR EXAMPLE, IN 1974, STATIC LEVELS AS HIGH AS 17,000VOLTS WERE DISCHARGED IN THE COMPUTER ROOM AT NEW YORK TELEPHONE AT VARIOUS TIMES OF THE DAY, CAUSING THE IBM 1130 COMPUTING SYSTEM TO BE OUT OFPARITY.THIS OCCURRED ON THE AVERAGE OF FIVE TIMES DAILY RESULTING IN ANENORMOUS NUMBER OF BILLING ERRORS.B. ESDS PART FAILURESTATIC VOLTAGES UP TO AND SOMETIMES EXCEEDING 15,000 VOLTSCAN BE GENERATED BY SIMPLE MOTIONS SUCH AS GETTING UP FROM A CHAIR,
2.WALKING ACROSS A ROOM, ROCKING IN A CHAIR, RUBBING OF CLOTHING AND THOUSANDS OF OTHER NORMAL, EVERYDAY PERSONNEL MOVEMENTS.SUCH STATIC VOLTAGESCAN DAMAGE ELECTRICAL AND ELECTRONIC COMPONENTS AND DEVICES (PARTS) SUCHAS INTEGRATED CIRCUITS (ICs), DISCRETE SEMICJNDUCTORS, THICK AND THINFILM DEVICES AND CRYSTALS.THE STATIC DANGER TO SOLID STATE SEMICONDUCTORSIS DUE TO THE EXTENSIVE USE OF THEN OXIDE LAYERS (E.G., MOS DEVICES) ANDTHE MICROMINIATURIZATION OF ACTIVE JUNCTIONS WHICH ARE SEVERELY LIMITEDIN THE POWER THEY CAN HANDLE.FILM RESISTORS ARE DAMAGED BY METALLIZATIONMELT; CRYSTALS BY MECHANICAL OVERSTRESS IN REACTION TO HIGH ESD VOLTAGE.THE ESD SENSITIVITY OF PARTS IS BECOMING MORE EVIDENT DURINGPRODUCTION, USE, TESTING, AND FAILURE ANALYSIS.THE CONSTRUCTION ANDDESIGN FEATURES OF CURRENT MICROTECHNOLOGY HAS RESULTED IN PARTS WHICHCAN BE DAMAGED BY ESD VOLTAGES AS LOW AS 20 VOLTS.THE TREND IN THIS TECH-NOLOGY IS TOWARDS GREATER COMPLEXITY AND INCREASED PACKAGING DENSITY; HENCESMALLER ACTIVE ELEMENTS AND THINNER DIELECTRICS BETWEEN ACTIVE ELEMENTS.THIS RESULTS IN PARTS THAT ARE BECOMING MORE AND MORE SENSITIVE TO ESD.WHILE CATASTROPHIC FAILURES OF ICs ARE A MAJOR PROBLEM, THEYBECOME OBVIOUS RATHER QUICKLY TO THE EQUIPMENT USER.SUBASSEMBLIES,ASSEMBLIES AND EQUIPMENT CONTAINING THESE ESDS PARTS ARE NORMALLY AS SENSITIVE AND IN SOME CASES MORE SENSITIVE THAN THE PARTS THEMSELVES.FOR EX-AMPLE, PRINTED CIRCUIT BOARD RUNS CAN ACT AS ANTENNAS GATHERING GREATERSTATIC VOLTAGES ACROSS SENSITIVE PART LEADS THAN SUBJECTING THESE INDIVIDUALPARTS TO ELECTROSTATIC FIELDS.C. TRANSIENT UPSET FAILUREA MORE SUBTLE PROBLEM, HOWEVER, IS THAT OF ELECTROSTATICDISCHARGES INDUCING NOISE INTO ESDS PARTS OR CIRCUIlRY.UNLIKE CATASTROPHIC
3.FAILURES, THESE SUBTLE FAULTS CAN GO UNDETECTED FOR A CONSIDERABLE PERIODOF TIME AND, ONCE DETECTED, CAN BE VERY DIFFICULT TO DIAGNOSE.DIGITALCIRCUITS ARE MUCH MORE SUSCEPTIBLE THAN LINEAR CIRCUITS TO THIS TYPE OFPROBLEM BECAUSE THEIR OPERATION DEPENDS UPON THE RECOGNITION AND PROCESSING OF PULSES.THE PRESENCE OF A STATIC DISCHARGE PULSE-LIKE NOISESPIKE CAN UPSET THE IC'S LOGIC PROCESS.FOR EXAMPLE, IN AMERICAN TELE-COMMUNICATION COMPANY'S AUTOMATIC DIALING EQUIPMENT, STATIC DISCHARGESCAUSED ERASURE OF THE TELEPHONE NUMBERS STORED IN MEMORY.D. TRANSMITTED FAILURESSIMILARLY, STATIC DISCHARGES CAUSED COUNTING FAULTS (ANDEVENTUAL FAILURE) IN INTERNATIONAL COMPUTING SCALE COMPANY'S COUNTINGSCALES.THE PROBLEM WAS RELATED TO THE ELECTROSTATIC CHARGE TRANSMITTEDTHROUGH THE FRONT-PANEL LEDs TO ITS ASSOCIATED PC BOARD BEHIND THE PANELCAUSING FAILURE OF SOME BOARD-MOUNTED ICs.MANY PARTS ALTHOUGH NOT SENSI-TIVE THEMSELVES TO ESD, CAN CONDUCT ESD PULSES THROUGH CIRCUITRY TO ESDSPARTS AND CAUSE THEIR FAILURE.E. THE ESO PROBLEMTODAY, ESD CONTROLS ARE NOT WIDELY IMPLEMENTED FOR ELECTRONICS.COMPREHENSIVE ESD CONTROL PROGRAM REOUIREMENTS GENERALLY HAVE NOT BEENCONTRACTUALLY SPECIFIED TO DATE AND RELATIVELY FEW CONTRACTORS HAVE TAKENTHE INITIATIVE TO IMPLEMENT ESD CONTROL PROGRAMS INTERNALLY AND IMPOSEEFFECTIVE ESD CONTROL REQUIkEMENTS ON THEIR SUBCONTRACTORS.WITH THEADVENT OF DOD-STD-1686 (REFERENCE 1), THIS WILL CHANGE IN THE NEAR FUTURE.PERHAPS ONE OF THE PRIME CAUSES FOR THE LACK OF IMPLEMENTATION OF ESDS CONTROLS IS THE LACK OF ESD AWARENESS FOR ALLII
4.FUNCTIONS FOR WHICH ESD CONTROLS ARE NECESSARY, SUCH AS:PROGRAM MANAGE-MENT, PROCUREMENT, ENGINEERING, MANUFACTURING, PACKAGING, STORAGE, FIELDMAINTENANCE AND QUALITY CONTROL.FEW CONTRACTORS HAVE ESTABLISHED ANDIMPLEMENTED INTERNAL ESD TRAINING PROGRAMS FOR THESE FUNCTIONS.ADDI-TIONALLY, THE HARDWARE, PACKAGING, DRAWINGS OR TECHNICAL MANUALS AREGENERALLY NOT MARKED SO THAT THE USERS ARE AWARE THAT THE HARDWARE THEYPROCURE, OPERATE AND MAINTAIN IN THE FIELD CONTAIN ESDS ITEMS.ESD TRAINING OR AWARENESS IS NOT LIMITED TO INDUSTRY.LACK OFMILITARY PERSONNELUSING ESDS EQUIPMENT ALSO GENERALLY LACK ESD TRAINING, AND ESD AWARENESSIS SELDOM INCLUDED IN EQUIPMENT TRAINING PROGRAMS CONDUCTED FOR MILITARYPERSONNEL BY CONTRACTORS.A PRIMARY REASON FOR THE LACK OF ESD AWARENESS TO DATE ISTHE LACK OF BASIC TECHNICAL DATA RELATING TO ESD.NUMEROUS PAPERS HAVEBEEN PUBLISHED IN VARIOUS MAGAZINES, PERIODICALS AND SYMPOSIUM PROCEEDINGS.HOWEVER, IT IS DIFFICULT FOR PEOPLE INTERESTED IN ESD TO GATHER ALL THISINFORMATION AND TO OBTAIN INFORMATION ON ALL ASPECTS OF AN ESD CONTROL PROGRAM FROM RANDOM ARTICLES.ADDITIONALLY, THERE ARE NUMEROUS AREAS RELATINGTO ESD FOR WHICH FEW ARTICLES HAVE BEEN PUBLISHED AND FOR WHICH CONSIDERABLERESEARCH IS REQUIRED.ESD IS NOT TAUGHT IN COLLEGE COURSES AND FEW BOOKS HAVE BEENWRITTEN ON THE SUBJECT.SYMPOSIUMS LIKE THE ELECTRICAL OVERSTRESS/ELECTRO-STATIC DISCHARGE (EOS/ESD) ARE METHODS FOR DISSEMINATING INFORMATION ON ESD.HOWEVER, SUCH SYMPOSIUMS ARE NOT ATTENDED BY ENOUGH PEOPLE, ARE TOO INFREQUENT, TOO SHORT, AND OFTEN UNTIMELY, TO PROVIDE ANSWERS TO THE EVERYDAYESD PROBLEMS PEOPLE ENCOUNTER IN THE FIELD OF ELECTRONICS.A FORMALCENTRALIZED ESD INFORMATION EXCHANGE IS REQUIRED TO COLLECT ESD DATA,PERFORM ENGINEERING ANALYSIS, AND DISSEMINATE THE LATEST INFORMATION ON
5.ESD; THE LATEST LISTING OF ESDS PARTS AND THEIR SENSITIVITIES THAT ARECONSTANTLY CHANGING WITH THE STATE-OF-THE-ART ADVANCEMENTS IN SOLID STATETECHNOLOGY; AND THE NEW PRODUCTS AND MATERIALS BEING DEVELOPED THAT CANSOLVE SOME OF THE MORE DIFFICULT PROBLEMS RELATING TO ESD.SUFFICIENTINFORMATION IS SELDOM PUBLISHED ON MATERIALS MARKETED FOR ESD CONTROLS.CHEMICAL AND PHYSICAL CHARACTERISTICS, USEFUL LIFE, STORAGE LIFE, AND KEYELECTROSTATIC CHARACTERISTICS SUCH AS PROTECTION AGAINST TRIBOELECTRICGENERATION, ELECTROSTATIC SHIELDINGATTENUATION AND PROTECTION AFFORDEDFROM CONTACT WITH CHARGED PERSONS OR OBJECTS ARE SELDOM PROVIDED BY THEMATERIAL MANUFACTURERS.THIS MAY IN PART BE DUE TO THE LACK OF FORMAL TESTMATERIALS AND STANDARD SPECIFICATION REQUIREMENTS FOR SUCH MATERIALS.ANOTHER BASIC PROBLEM IS THAT FAILURES ARE OFTEN NOT RECOGNIZEDAS RELATED TO ESD.FAILURES CAUSED BY ESD ARE OFTEN ANALYZED AS ELECTRICALOVERSTRESS FAILURES AND BLAMED ON POWER LINE TRANSIENTS OR TECHNICIANSIMPROPERLY HOOKING UP, PROBING OR TESTING AN ASSEMBLY WITH TOO HIGH A VOLTAGE.OTHER FAILURES CAUSED BY ESD ARE OFTEN CATEGORIZED AS RANDOM, UNKNOWN,INFANT MORTALITY, OR MANUFACTURING DEFECT DUE TO THE LACK OR DEPTH OFFAILURE ANALYSIS PERFORMED.A MAJOR REASON FOR THE ABOVE IS THAT FEWFAILURE ANALYSIS LABORATORIES ARE EQUIPPED WITH SCANNING ELZCTRON MICROSCOPES OR OTHER EQUIPMENT AND TECHNOLOGY REQUIRED TO TRACE FAILURES TO ESD.ALSO, ESD CAUSED FAILURES CAN OFTEN BE OVERLOOKED IF THE FAILURE ANALYSISTECHNICIANS ARE NOT PROPERLY TRAINED.MANY MANUFACTURERS OF ELECTRONICEQUIPMENT CONTAINING ESDS PARTS ACCEPT A PERCENTAGE OF PART FAILURES ASNORMAL PRODUCTION FALLOUT WHEN MANY MAY BE CAUSED BY ESD.THE USER INTHE FIELD OFTEN ACCEPTS THE HIGHER OPERATIONAL FAILURE RATES OF EQUIPMENTCONTAINING ESDS ITEMS AS NORMAL AND INSTEAD OF INVESTIGATING THE CAUSE OFTHE HIGH NUMBER OF FAILURES SIMPLY PROCURES GREATER QUANTITIES OF SPARES.
6.LACK OF ESD AWARENESS OFTEN RESULTS IN PERSONNEL LIMITING ESD HANDLINGPRECAUTIONS TO THE MOST NOTORIOUS ESDS PARTS (E.G., METAL OXIDE SEMICONDUCTORS (MOSs)) WITHOUT KNOWING THAT FAILURES OF NUMEROUS OTHER PARTSARE BEING CAUSED BY ESD.THE LACK OF ESD AWARENESS ALSO CONTRIBUTES TOTHE FALSE SENSE OF SECURITY THAT AN ESDS PART CONTAINING BUIT-IN PROTECTIVE CIRCUITRY IS COMPLETELY PROTECTED FROM ESD, NOT KNOWING THAT MOSTPROTECTIVE CIRCUITRY NORMALLY DECREASES SENSITIVITY BY ONLY SEVERAL HUNDREDVOLTS.ESD CAN RESULT IN LATENT DEFECTS WHERE THE ITEM WILL OPERATE WITHINSPECIFICATION LIMITS DURING TEST, BUT WILL FAIL AFTER BEING DELIVERED TOTHE USER.IN ALL OF THE ABOVE INSTANCES, ESD AS A CAUSE OF FAILURE IS NOTALWAYS RECOGNIZED AND HENCE ESD CONTROL MEASURES ARE NOT IMPLEMENTED.RECOGNIZING THESE PROBLEMS, THE NAVAL SEA SYSTEMS COMMAND HASDEVELOPED DOD-STD-1686 FOR DEFINING ESD CONTROL PROGRAM REQUIREMENTS ANDDon-HDBK-263 TO PROVIDE GUIDELINES FOR IMPLEMENTING THESE REQUIREMENTS.F. ESTABLISHED ESD CONTROL PROGRAM REQUIREMENTSESD CONTROL PROGRAM REQUIREMENTS ARE NOT COMPLETELY NEW.MANY ESTABLISHED MILITARY SPECIFICATIONS AND STANDARDS COMMONLY IMPOSEDON EQUIPMENT MANUFACTURERS REQUIRE CONTROLS FOR PROTECTION OF ESDS ITEMS.FOR EXAMPLE, MIL-Q-9858 "QUALITY PROGRAM REQUIREMENTS" (REFERENCE 2)REQUIRES THAT WORK INSTRUCTIONS BE DEVELOPED FOR ALL WORK AFFECTING THEQUALITY OF EQUIPMENT INCLUDING HANDLING, ASSEMBLING, FABRICATING,PROCESSING, INSPECTION, TESTING, MODIFICATIONS, ETC., AND THAT HANDLING,STORAGE, PRESERVATION, PACKAGING AND SHIPPING WORK AND INSPECTION INSTRUCTIONS PROTECT THE QUALITY OF PRODUCTS AND PREVENT LOSS, DETERIORATION ORDEGRADATION OF PRODUCTS.
7.MIL-STD-785, "RELIABILITY PROGRAM FOR SYSTEMS AND EQUIPMENTDEVELOPMENT AND PRODUCTION" (REFERENCE 3) REQUIRES THE EFFECTS OF PACKAGING, TRANSPORTATION, HANDLING AND MAINTENANCE ON THE RELIABILITY OFTHE END PRODUCT BE DETERMINED AND THAT CRITICAL CHARACTERISTICS OF ITEMSTHAT DETERIORATE WITH ENVIRONMENTAL CONDITIONS BE IDENTIFIED.PERHAPS THE STRONGEST ESTABLISHED REQUIREMENTS FOR ESD CONTROLS ARE FOUND IN MIL-STD-882, "SYSTEM SAFETY PROGRAM REQUIREMENTS"(REFERENCE 4) WHICH INCLUDE: IDENTIFICATION OF CRITICAL PATHS, ASSEMBLIES,PRODUCTION TECHNIQUES, ASSEMBLY PROCEDURES, FACILITIES, TESTING AND INSPECTION REQUIREMENTS WHICH MAY AFFECT SAFETY (INCLUDING MATERIAL SAFETY);ENSURE SAFETY WITHIN THE PRODUCTION PROCESS; PROVIDE WARNINGS AND CAUTIONSIN TECHNICAL MANUALS AND PRODUCTION PROCESSES, OPERATION, STORAGE, PACKAGING AND HANDLING; USE DESIGN TECHNIQUES AND SAFETY DEVICES TO MINIMIZEHAZARDS TO SAFETY (INCLUDING MATERIAL SAFETY); ELIMINATION OR CONTROL OFHAZARDS RESULTING FROM ENVIRONMENTAL CONDITIONS INCLUDING SPECIFICALLY:"ELECTROSTATIC DISCHARGE"; INCLUSION OF SAFETY (INCLUDING MATERIAL SAFETY)PROCEDURES IN INSTRUCTORS' LESSON PLANS AND STUDENT EXAMINATIONS FOR THETRAINING OF'ENGINEERS, TECHNICIANS, OPERATING AND MAINTENANCE PERSONNEL ANDREQUIREMENTS FOR AN AUDIT PROGRAM TO ENSURE THAT THE OBJECTIVES AND REQUIREMENTS OF THE SAFETY PROGRAM ARE BEING ACCOMPLISHED.THE ABOVE IS A SMALL SAMPLING OF ESTABLISHED MILITARY DOCUMENTSWHICH REQUIRE SOME OF THE BASIC ELEMENTS OF AN ESD CONTROL PROGRAM THATARE COMMONLY IMPOSED UPON DOD CONTRACTORS.A MORE COMPLETE LISTING OFTHESE DOCUMENTS AND THEIR REQUIREMENTS PERTAINING TO AN ESD CONTROL PROGRAMARE SUMMARIZED IN NAVSEA S6000-AB-GTP-OIO, "MILITARY SPECIFICATIONS, STANDARDS AND CONTRACT CLAUSES SPECIFYING CONTROLS FOR PROTECTION AGAINSTELECTROSTATIC DISCHARGE" (REFERENCE 5).!
8.F. IMPACT OF NOT IMPLEMENTING ESD CONTROLSTHE IMPACT OF NOT IMPLEMENTING EFFECTIVE AND COMPREHENSIVEESD CONTROLS CAN BE COSTLY TO BOTH THE MANUFACTURER AND THE USER.ESD FAILURES AT THE MANUFACTURER'S PLANT RESULT IN REPLACEMENT COSTS FOR FAILED PARTS AND REWORK AND REPAIR COSTS IF FAILURES OCCURAT THE ASSEMBLY LEVEL OR AFTER THE EQUIPMENT ASSEMBLY HAS BEEN COMPLETED.THE HIGHER THE ASSEMBLY LEVEL AT WHICH THE FAILURE OCCURS THE GREATER ARETHE COSTS.UNSCHEDULED MAINTENANCE RESULTING FROM ESD RELATED FAILURESCOULD IMPACT DELIVERY SCHEDULES.THE EQUIPMENT DOWNTIME NEEDED TO EFFECTA REPAIR IS NOT NORMALLY EXCESSIVE FOR ELECTRONIC EQUIPMENT GIVEN THATSUFFICIENT REPLACEMENT PARTS ARE AVAILABLE.IF A MANUFACTURER DESTROYSHIS INVENTORY OF A SPECIFIC PART DUE TO THE LACK OF ADEQUATE ESD CONTROLS,THE EQUIPMENT COULD BE DOWN FOR A SUBSTANTIAL PERIOD AWAITING PRODUCTIONAND DELIVERY OF A REPLACEMENT PART.IN THE FIELD THE USER NORMALLY ABSORBS THE BURDEN OF THESECOSTS EXCEPT IN INSTANCES WHERE THE MANUFACTURER WARRANTS THE EQUIPMENT.IN EITHER CASE, SUCH COSTS CAN BE SUBSTANTIAL IF THE MANUFACTURER MUST SENDA FIELD ENGINEER TO A USER FACILITY TO EFFECT A REPAIR.FOR THE USER, EQUIPMENT FAILURES RESULTING FROM ESD CAN REQUIREINCREASED MAN-LOADING TO KEEP THE EQUIPMENT OPERATIONAL, INCREASED SPARESUSAGE, GREATER BURDEN ON THE SUPPLY SYSTEM, AND OTHER LOGISTICS SUPPORTCOST INCREASES.AN INCREASE IN THE NUMBER OF FAILURES MEANS A DECREASE INEQUIPMENT REALIBILITY, INCREASED DOWNTIME FOR MAINTENANCE AND INCREASED
9.PROBABILITY OF WAITING FOR A SPARE PART THAT IS NOT ON HAND.THIS DE-CREASE IN RELIABILITY AND INCREASE IN DOWNTIME MEANS LOWER AVAILABILITYOF THAT EQUIPMENT.ALL OF THE ABOVE RELATE TO HIGHER LIFE CYCLE COSTS FOR ANEQUIPMENT WHETHER THEIR COSTS BE BORNE BY THE MANUFACTURER OR USER.FORMILTIARY EQUIPMENT CRITICAL TO COMBAT SITUATIONS THE DECREASED RELIABILITYAND INCREASED DOWNTIME RELATES TO DECREASED MILITARY READINESS AND EFFECTIVENESS.' I-[
10.II.PRINCIPLES OF STATIC ELECTRICITYA. BACKGROUNDSTATIC ELECTRICITY IS THE OLDEST KNOWN FORM OF ELECTRICITY.THE GREEKS WERE ACQUAINTED
electrical and electronic parts, elements of an esd control program, esd protec-tive materials, esd protective equipment, packaging and marking of esds items, esd in design, esd handling precautions and procedures, and monitoring of esd control programs._- -c nding officer nava ublications
