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NASA-HDBK 8739.213DEFINITIONSThe following definitions apply to terms used in this manual:AssemblyA functional subdivision of a component, consisting of parts orsubassemblies, which perform functions necessary for the operation of thecomponent as a whole. Examples: regulator assembly, power amplifierassembly, gyro assembly, etc.Certificate of Completion of Training The actual certificate issued or the wallet-sized card given tothe trainee after successful completion of training.CertificationThe act of verifying and documenting that personnel, facilities, equipment,processes, or materials comply with the requirements of this document.Certification of Competence The act of verifying and documenting that personnel are competent toperform work in an ESD-protected area as required by this document.Certification of Training The act of verifying and documenting that personnel have successfullycompleted training. The Certification of Completion of Training documentsthis certification.Charged Device Model A specified circuit characterizing an electrostatic discharge, which resultswhen a device isolated from ground is first charged and then subsequentlygrounded.Cheater PlugAn AC plug adapter used to connect a three-pronged plug to a two-prongedAC socket. It can be used to separate the ground wire from the socket fortesting purposes.ComponentA functional subdivision of a system, generally a self-contained combinationof assemblies performing a function necessary for the system's operation.Examples: power supply, transmitter, gyro package, etc.ContractorThe individual(s) or concern(s) who enter into a prime contract with theGovernment.Conductive MaterialA material that has a surface resistivity of 105 ohms per square or a volumeresistivity 104 ohms-cm.Equipotential Bonding A connection between two points with a maximum resistance between themof 109 ohms [with no current flow].Electrostatic Discharge (ESD) A transfer of electrostatic charge between bodies at differentelectrostatic potentials caused by direct contact or induced by an electrostaticfield.ESD ADV ESDA Advisory Document. Advisory Documents are not standards, butprovide general information for the industry or additional information to aidin better understanding of ESD Association standards.ESD DS ESDA Draft Standard. Draft standards, test methods and standard practicesare subject to revision before being issued as full standards.13

NASA-HDBK 8739.21ESD S ESDA Standard. Standards have completed the industry comment andreview process, and have been approved by the ESD Association StandardsCommittee as final standards documents.ESD SP ESDA Standard Practice. Standard practices have completed the industrycomment and review process, and have been approved by the ESDAssociation Standards Committee as final standards documentsESD STM ESDA Standard Test Methods. Standard test methods have completed theindustry comment and review process, and have been approved by the ESDAssociation Standards Committee as final standards documents.ESD TR ESDA Technical Report. A technical report is a collection of technical dataor test results published as an informational reference on a specific material,product, system or process. The opinions expressed in a technical report arethe opinions of the author(s) and may or may not be endorsed by the ESDAssociation.ESD Program Monitor An individual who is trained and certified who are responsible for the day-today maintenance of the certification status of an ESD protected area.ESD Protected AreaAn area that is constructed and equipped with the necessary ESD-protectivematerials and equipment to limit ESD voltage below the sensitivity level ofESDS items handled therein. This may include benches, rooms or buildings.ESD-Protective Material Material capable of one or more of the following functions: limiting thegeneration of static electricity; safely dissipating electrostatic charges over itssurface or volume; or providing shielding from ESD spark discharge orelectrostatic fields.ESD-Protective Packaging Packaging with ESD-protective materials to prevent damage to ESDSitems during storage or transport.ESD Protected Workstation See ESD Protected Area.ESD Sensitive (ESDS) Items Electrical and electronic parts, assemblies and equipment which aresensitive to ESD voltages or electrostatic fields.Electrostatic FieldA voltage gradient between an electrostatically charged surface and anothersurface of a different electrostatic potential.GroundA mass such as earth, a ship, or a vehicle hull, capable of supplying oraccepting a large electrical charge.Groundable PointAny point with low impedance to ground where grounding may be attached.Usually it is the common point ground.Hard GroundA connection to earth ground either directly or through low impedance.Human Body ModelAn electrostatic discharge circuit that meets the set model values byconforming to waveform criteria specified in ESD-STM 5.1, characterizingthe discharge from the fingertip of a typical human being.14

NASA-HDBK 8739.21Insulative MaterialA material having a surface resistivity 1012 ohms/square or a volumeresistivity 1011 ohms-cm.KitA prepared package of parts with instructions for assembly and/or wiring acomponent or chassis.Level B InstructorAn individual who is certified to train operators and ESD program monitors.Certified Level B Instructors are qualified to perform the duties of an ESDprogram monitor.Machine ModelAn electrostatic discharge simulation test based on a discharge networkconsisting of a charged 200 Pico farad capacitor at (nominally) zero ohms ofseries resistance. Actual series resistance and inductance are specified interms of the current waveform through a shorting wire. The simulation testapproximates the electrostatic discharge from a machine. (See ESD STM5.2)OperatorAn individual who is trained and certified to perform tasks in an ESDprotected area.OrganizationA NASA center, support contractor, supplier, department, group or team.PartAn element of a component, assembly, or subassembly which is not normallysubject to further subdivision or disassembly without destruction of itsdesigned use, e.g., a module, IC, resistor, etc.Soft GroundA connection to ground through impedance sufficiently high to limit currentflow to safe levels for personnel (normally 5 milliamperes). Impedanceneeded for a soft ground is dependent upon the voltage levels which could becontacted by personnel near the ground. By this definition a hard groundprotected by a functional GFCI is considered a soft ground.Static DissipativeA property of a material having surface resistivity 105 but 1012 ohms persquare or a volume resistivity 104 but 1011 ohms-cmSubcontractorAn individual or concern that enters into a purchase agreement under aGovernment prime contract.Surface Resistivity.The surface resistivity is an inverse measure of the conductivity of a material.Surface resistivity of a material is numerically equal to the surface resistancebetween two electrodes forming opposite sides of a square. The size of thesquare is immaterial. Surface resistivity applies to both surfaces andmaterials with constant volume conductivity and has the value of ohms persquare.SystemA system is a functional subdivision of a spacecraft generally composed oftwo or more components designed to perform an operation. An instrument isconsidered a system.VerificationThe act of performing the tests and/or inspections required in Table 7-1 andreviewing ESD protected areas for compliance to the requirements of thisManual.TriboelectricPertaining to electricity generated by friction.15

NASA-HDBK 8739.2144.1GENERALCONFIGURATION CONTROL4.1.1 This document is a controlled document and is controlled by NASA Headquarters OSMAconfiguration management procedures.4.1.2 Requests for technical changes are processed in accordance with NASA Headquarters OSMAconfiguration management procedures.4.2IMPLEMENTATION4.2.1 ESD Control Program Plans which conform to the recommendations in this handbook includerequirements related to facility preparation and certification, records management, assignment ofresponsible personnel, manager and operator training, assessment of the sensitivity of the hardware tobe handled, and declaration and use of special processes and criteria as applicable. It is intended thatrecommendations herein, made using language such as “is”, “are”, “should”, and “will”, will beconverted to “shall” statements in the local ESD Control Program Plans.4.2.2 Suppliers should provide a central ESD Point of Contact (POC) that can advise and assistoperators, Program Monitors, contractors, subcontractors and other authorized personnel in the properand effective implementation of the provisions of this handbook. This person can be the ESD ControlProgram Manager that is required by ANSI/ESDA S20.20-2007 [2].4.2.3 The methods described in this handbook for developing an ESD Control Program Plan areimplemented directly by operators, Program Monitors, Audit Teams, Audit Coordinators, andProgram Managers.4.2.4 The needed ESD Protected Area (EPA) certification level and associated ESD event model aredetermined by the hardware designer based on the most sensitive piece-part to be handled. Therecommended default EPA certification level is HBM Class 1A (See Table 5-1). Where the HumanBody Model (HBM) does not provide sufficient protection for the hardware, the Machine Model(MM) or the Charged Device Model (CDM) should be considered when designing the ESD protectedarea. (See 5.7). For areas required to protect extremely sensitive devices see paragraph 8.2.4.2.5 Use of the guidelines herein facilitates compliance to NASA Agency-level ESD requirementshowever it does not supersede or preclude Project review and approval of suppliers’ ANSI/ESDS20.20-complient ESD Control Program Plans. It is the Project’s responsibility for assuring that localESD Control Program Plans meet the requirements of ANSI/ESD S20.20 as well as Project-specificrequirements. However, it is recommended that Projects utilize this document as a benchmark againstwhich suppliers’ plans are evaluated.16

NASA-HDBK 8739.214.3RECORDSRecords required by the processes described herein should be retained per Table 4-1 below.Table 4-1: Record RetentionRecord TitleRecord CustodianTraining recordsOffice of Human Resourcesand/or Supervisor.ESD workstation recordsLaboratory Manager or owningproject manager when there isno Program ManagerTemporary/IntermittentWorkstation recordsProject ManagerRetentionNRRS 3/33G1* -- Destroy 5 years afteremployee discontinues or completestraining.NRRS 8/109* -Temporary- Destroy/deletewhen between 2 & 15 years old. Do notretain longer than life of program/projectplus 5 years.NRRS 8/109**NRRS – NASA Records Retention Schedules (NPR 1441.1)17

NASA-HDBK 8739.215ESD CONTROL PROGRAM5.1GENERAL5.1.1 The intent of this ESD Control Program Guide meets or exceeds the requirements ofANSI/ESD S20.20 as well as the NASA ESD Workmanship requirements for processing ESDsensitive equipment.5.1.2 Proper control of ESD is critical at every process step that an electronic part may see, frompart manufacturing through testing and shipment, to incorporation on printed wiring boards, electronicmodules, and directly into boxes.5.2ELECTROSTATIC DISCHARGE (ESD) TECHNICAL OVERVIEW [15]5.2.1 ESD is the sudden transfer of electrical charge between two objects at different potentials.Almost everyone has experienced ESD. One example occurs when you, wearing shoes, walk across acarpet and touch a conductive object, such as a metal doorknob. The “zap” that you feel and hear is aform of ESD.5.2.2 The human body or other conductive objects can become electrostatically charged if notproperly grounded. If this charge comes in contact with or passes near an ESD sensitive (ESDS)device, ESD damage can occur. Charge is not localized on the surface of a conductor, but is spreadout uniformly over the conductor’s surface. Thus, very low voltages are capable of damaging ESDSdevices.5.2.3 Cathode ray tubes and other high voltage electric devices can create high electrical fieldpotentials. Moving an ESDS device through such a field can induce current to flow through thedevice, thus causing damage even if the device does not come into contact with the charged surface.In addition, grounding a device that has become charged in an external electrostatic field can causedamage.5.2.4 The physical structures on modern devices are extremely small and continue to shrink in sizeas technology advances. Very small charges accumulated on conductive elements of a device canexceed the breakdown potential of the insulating layers or the air gaps between them, causing thedevice to destroy itself. The presence of mechanical

administrative and technical baseline for development of an organization's ESD Control Program Plan which is required by ANSI/ESD S20.20. Note: While providing a recommended ESD Control Program Plan in a format that facilitates direct use of its text (starting at paragraph 4.3) by authors of supplier-level ESD Control Program Plans, this