scope:

This document prescribes the minimum design, critical process and acceptance requirements for the application of polymeric materials to electrical/electronic components, modules, printed wiring assemblies and other elements thereof.

IPC-AJ-820, IPC-HDBK-001, IPC-HDBK-830 and IPC-HDBK-850 are companion documents to this specification. They contain valuable explanatory and tutorial information compiled by IPC Technical Committees that is relevant to this specification.

Although the handbooks are not a part of this specification, when there is confusion over the specification verbiage, the reader is encouraged to refer to the handbooks for assistance.

Reference materials listed in this text are recommended reading. The User is encouraged to obtain all relevant referenced materials as this document cannot (nor can any single document) cover every material, process, environment, performance or safety aspect that affects a given design.

Purpose

The intent of this document is to establish a baseline of requirements, procedures, practices and process attributes based on Lessons Learned and Best Practices that have been demonstrated through use and experience, to result in a robust design and high reliability.

This document is intended for use by the design engineer, manufacturing engineer, quality engineer or other individual responsible for implementation and compliance with requirements of this document to the applicable performance class.

a. In-Service Criteria. This document defines design requirements and acceptability criteria for "New/Beginning of Life" hardware. It is not the intent of this document to establish or define "In Service" acceptance criteria to address performance or reliability issues caused by aging or use. However, the acceptability criteria and limits that are currently detailed in this document may be considered to be wide enough to be applicable to the more common hardware degradation caused by aging/use. Use of these criteria for acceptance of "In Service" hardware conditions shall [N1D2D3] be as agreed between the Manufacturer and the User.

b. Metallic Whisker Control. It is not the intent of this document to be used as a stand-alone document for the control and mitigation of performance and/or reliability concerns related to metallic whiskers.

Note: Users of this document are encouraged to review GEIA-STD-0005-1, GEIA-STD-0005-2 or IPC-AJ-820 for additional information pertaining to control of metallic whiskers.

c. Alternate/Proprietary Documents or Processes. It is not the intent of this document to exclude any alternate or manufacturer-proprietary documents or processes that meet or exceed the baseline of requirements established by this document. Use of alternate or manufacturer-proprietary documents or processes that tailor (e.g., change, increase, reduce, delete) any of the mandatory requirements of this document shall [N1D2D3] require review and prior approval of the User.

d. For purposes of this document:

1) The Designer is the design agent for the User.

2) The User is the individual, organization, company, contractually designated authority or agency responsible for the procurement or design of electrical/electronic/electromechanical (EEE) hardware and having the authority to define the class of equipment and any variation or restrictions to the requirements of this document (e.g., the originator/custodian of the contract detailing these requirements).

3) The Supplier is considered the individual, organization or company which provides the Manufacturer (Assembler) components (e.g., electrical, electronic, electromechanical, mechanical, printed boards) and/or materials (e.g., solder, flux, cleaning agents).

4) The Manufacturer is considered the entity that provides a service or product to the User.

e. The acceptability of the use of polymerics with no-clean flux chemistries shall [N1D2D3] be as agreed between the Manufacturer and the User.

Applicability

This document is applicable to manufacturers involved in the application of polymeric processes (e.g., bonding, staking, conformal coating, encapsulation) to electrical/electronic components, including printed board assemblies, optical and metallic cable and wiring harness assemblies, mechanical items (e.g., tin-plated chassis, brackets, fasteners), and elements thereof, and wherever invoked contractually. The User is responsible for determining whether the use of polymeric materials may be required to ensure performance or reliability of the hardware.

Performance/Product Classification

This document recognizes that electrical and electronic assemblies are subject to classifications by intended end-item use. Three general end-product classes have been established to reflect differences in functional performance requirements, and verification (inspection/test) frequency.

a. It should be recognized that there may be overlaps of equipment between classes.

b. The User is responsible for defining the product class.

c. The contract should specify the performance class required, whether compliance to any of the Appendices is required, and indicate any exceptions to specific parameters where appropriate. If the performance Class is not specified, Class 3 requirements are applicable.

CLASS 1 - General Electronic Products

Includes products suitable for applications where the major requirement is function of the completed assembly.

CLASS 2 - Dedicated Service Electronic Products

Includes products where continued performance and extended life is required, and for which uninterrupted service is desired but not critical. Typically, the end-use environment would not cause failures.

CLASS 3 - High Performance Electronic Products

Includes products where continued high performance or performance-on-demand is critical, equipment downtime cannot be tolerated, end-use environment may be uncommonly harsh, and the equipment must function when required, such as life support or other critical systems.

MILITARY/SPACE

Includes products from Performance Class 3 - High Performance/Harsh Environment Electronic Products, with additional considerations for unique materials requirements and more extreme operational environments, such as vibration and thermal cycling. Space/military classification deviations to IPC-A-5262 requirements are defined and listed in Appendix A.

When the [M/S] symbol appears next to a paragraph, it indicates that Appendix A contains requirements to be used in addition to, and in some cases in place of, those published in that paragraph. The criteria in Appendix A are not binding, unless separately and specifically included by the applicable contract, approved drawing(s), or purchase order. Appendices do not apply unless separately invoked per 1.13.

Definition of Requirements

The imperative form of action verbs are used throughout this document to identify acceptance requirements that may require compliance, depending upon the Performance Classification of the hardware.

SHALL/SHALL NOT.

The words shall or shall not are used whenever a requirement is intended to express a provision that is mandatory. Deviation from a shall or shall not requirement for a particular Performance Class may be considered if sufficient technical rationale/objective evidence (OE) is supplied to the User to justify the exception.

d. SHOULD/SHOULD NOT.

The words should or should not are used whenever a requirement is intended to express a provision that is non-mandatory, and which reflects general industry practice and/or procedure.

e. MAY.

The word may is intended to express an action or provision that is to be considered non-mandatory, and which is provided as a "recommendation".

Requirement Format (N/A/D)

To assist the User, each requirement is identified by its Performance Classification (x1x2x3) and applicability, where "x" represents:

N = No requirement has been established for this Class

A = Acceptable

D = Defect

Examples:

• [N1N2D3] is Requirement Not Established Class 1 or 2, Defect Class 3

• [N1D2D3] is Requirement Not Established Class 1, Defect Classes 2 and 3

• [N1A2D3] is Requirement Not Established Class 1, Acceptable Class 2, Defect Class 3

• [A1A2D3] is Acceptable Classes 1 and 2, Defect Class 3

• [D1D2D3] is Defect for all Classes.

a. A defect for a Class 1 product means that the characteristic is also a defect for Class 2 and 3.

b. A defect for a Class 2 product means that the characteristic is also a defect for a Class 3 product but may not be a defect for a Class 1 product where less demanding criteria may apply.

Material and Process Nonconformance

Hardware characteristics or conditions that do not conform to the requirements of this specification are classified as either hardware defects or hardware process indicators.

a. For purposes of this document:

- A Defect is a condition that may affect the form, fit, or function of the item in its end use environment, or other risk factors as identified by the Manufacturer.

- Disposition is the determination of how defects are to be treated, and include, but are not limited to, rework, scrap, use as-is, or repair.

b. It is the responsibility of the User to define additional or unique defect categories applicable to the product.

c. It is the responsibility of the Manufacturer to identify defects that are unique to the assembly process.

d. Hardware found to be produced using either materials or processes that do not conform to the requirements of this standard shall [N1D2D3] be dispositioned to address the potential effect of the nonconformance on functional capability of the hardware such as reliability and design life (longevity).

Note: Material and process nonconformance differs from hardware defects or hardware process indicators in that the material/process nonconformance often does not result in an obvious change in the hardware's appearance but can impact the hardware's performance.

Requirements Flowdown

a. This document shall not [N1D2D3] be binding, unless separately and specifically included by the applicable contract, approved drawing(s) or purchase order.

b. When invoked, the applicable requirements of this document shall [N1D2D3] be imposed on all applicable subcontracts, assembly drawing(s), documentation and purchase orders.

Notes/Italicized Text

Information provided in Notes or presented as italicized text is for informational purposes only.

Commercial Off-The-Shelf (COTS)

The requirements of this document shall not [N1D2D3] apply to suppliers of Commercial- Off-The-Shelf (COTS) or catalog items (e.g., components, assemblies, subassemblies, hardware).

a. The design and workmanship of COTS items should be evaluated and modified as required to ensure that the COTS items meet contract performance and reliability requirements in the expected worst-case use environment.

b. Modifications of COTS shall [N1D2D3] be documented.

c. All modifications shall [N1D2D3] meet the applicable requirements of this document for the specified Product Class, and be completed, inspected, and tested in accordance with this document, unless otherwise specified by the User.

Existing or Previously Approved Designs

The requirements of this document shall not [N1D2D3] constitute the sole cause for the redesign of previously approved designs.

a. When drawings for existing or previously approved designs undergo revision, they should be reviewed and changes made that allow for compliance with the requirements of this document.

b. If the review results in any material or part changes to a currently qualified design, the revised drawing shall [N1D2D3] be subject to User approval.

Measurement Units and Applications

All dimensions and tolerances, as well as other forms of measurement in this standard, are expressed in SI (System International) units, with Imperial English equivalent dimensions provided in [brackets], except as noted.

a. Linear dimensions and tolerances use centimeters (cm) [inches (in)] as the main form of dimensional expression; millimeters (mm) [inches (in)] or micrometers (μm) [microinches (μin)] are used when the required precision makes the use of centimeters (cm) too cumbersome.

b. Temperature values are expressed in degrees Celsius (°C) [Fahrenheit (°F)].

c. Mass is expressed in grams (g) [ounces (oz)].

d. Wire, wire harness and cable diameters are expressed in the nondimensional unit (d), where a numerical dimension, such as 2d, is solely dependent on a physical attribute of the hardware (e.g., wire gauge, harness diameter).

e. Time values are expressed in hours, minutes and seconds (hh:mm:ss).

Use of Measurement Units

All specified measurement units in this standard are defined as "nominal."

Verification of Dimensions

Actual measurement of specific dimensions and determination of percentages are not required, except for referee purposes or when specified by contract. For determining conformance to the measurement units specified in this Standard, round all observed or calculated values ''to the nearest unit'' in the last right-hand digit used in expressing the specification limit (e.g., the retained digit), in accordance with ASTM E29 (Rounding Procedure].

Definition of Terms

For purposes of this document, the acronyms, abbreviations, and terms used, but in addition to those listed in IPC-T-50 are listed in Section 9.

Engineering Documentation

The engineering documentation shall [N1D2D3] identify the appropriate Product Class and depict all applicable design and acceptance details.

Order of Precedence

The contract shall [N1D2D3] take precedence over this document, referenced standards and drawings.

Conflict

a. In the event of conflict between the requirements of this document and the approved assembly drawing(s)/documentation, the User-approved assembly drawing(s)/documentation governs.

b. In the event of a conflict between the text of this document and the applicable documents cited herein, the text of this document takes precedence.

c. In the event of conflict between the requirements of this document and an assembly drawing(s)/documentation that has not been User approved, this document governs.

Clause References

When a clause in this document is referenced, its subordinate clauses also apply.

Line Drawings and Illustrations

Line drawings and illustrations are depicted herein to assist in the interpretation of the written requirements of this standard. The written requirement always takes precedence over the drawings and illustrations.

Appendices

For the purpose of this document, the Appendices are considered separate and optional documents, which provide additional engineering rationale and technical guidance on polymeric processes.

a. Appendices are not binding, unless separately and specifically included by the applicable contract, approved drawing(s) or purchase order.

b. When invoked, the applicable requirements of the appendices shall [N1D2D3] be imposed on all applicable subcontracts, assembly drawing(s), documentation and purchase orders.

c. When not invoked, the Manufacturer may implement the Appendices, individual requirements of the Appendices and/or flowdown of said appendices and/or individual requirements.

Approval of Departures from Standards and Requirements

Special engineering or design requirements may exist which are not covered by, do not comply with or which are in conflict with program-specific documents, and/or program-specified design requirements.

Use of alternate control plans, documents or processes shall [N1D2D3] require technical evaluation and approval of the User prior to use.

Personnel Proficiency

All instructors, operators and inspection personnel shall [N1D2D3] be proficient in the tasks to be performed.

a. Objective evidence of that proficiency shall [N1D2D3] be maintained and be available for review.

b. Objective evidence shall [N1D2D3] include records of training to the applicable job functions being performed, work experience, testing to the requirements of this standard and/or results of periodic reviews of proficiency.

c. Supervised On-the-Job Training (OJT) shall [N1D2D3] be acceptable until proficiency is demonstrated.

Acceptance Requirements

All products shall [N1D2D3] meet the requirements of the assembly drawing(s)/documentation and the applicable requirements for the product class specified herein.

a. Manufacturers shall [N1D2D3] perform 100% inspection unless sampling inspection is defined as part of a documented process control plan.

b. The User has the responsibility to specify acceptance criteria. If no criteria are specified, required or cited, then best manufacturing practice shall [N1D2D3] apply.

Facilities

Work areas/facilities used for the mixing, application, cure and testing of polymeric materials shall [N1D2D3] be classified as a Controlled Work Area (CWA).

Controlled Work Area (CWA): For the purpose of this document, a Controlled Work Area (CWA) is defined as an assembly/processing area that is designed, maintained and monitored to achieve shop cleanliness, environmental control and Foreign Object Debris (FOD) mitigation, either by process or procedure, to limit the entry of contamination, and/or environmental conditions that would interfere with the application and complete cure of the polymeric materials, or damage/degrade the hardware.

See Section 4 for additional guidance/requirements.

Health and Safety

The use of some materials referenced in this standard may be hazardous. To provide for personnel safety, follow the applicable local and Federal (National) occupational, safety and health regulations.

Warning:

Chemicals, materials and solvents used in the application, cure, rework and/or repair of polymeric materials may represent serious human health, safety and environmental concerns. Follow government and the material manufacturer's precautions and guidelines for storing, handling, transporting, staging and disposal of hazardous waste.

Caution:

The ingestion of chemicals, materials and/or solvents used in the application, cure, rework and/or repair of polymeric materials through the act of smoking (including the use of tobacco, non-tobacco, vapor products, etc.), eating and/or drinking may be detrimental to human health.

Packaging, Handling, Shipping and Transportation (PHS&T)

a. Hardware shall [N1D2D3] be packaged, handled, shipped and transported in accordance with the PHS&T requirements specified in the detail specification and/or contract.

b. All polymeric materials shall [N1D2D3] be fully cured in accordance with a documented procedure or per material specification prior to shipment of the item.

Documentation Requirements

The documentation package shall [N1D2D3] be in accordance with ASME Y14.100 (including subset Y14.24, Y14.34, Y14.35, and Y14.44), the User-specified format or an equivalent format agreed upon by the Designer and User. See Section 8 for additional guidance/requirements.

Intellectual Property (IP) Control Requirements

The use, control and disposition of tangible and intangible information related to the design and manufacture of the product, including data, drawings, engineering documentation, trade secrets, etc., should be in accordance with IPC-1791, the User-specified control plan or an equivalent control plan agreed upon by the Designer and User.

Supply Chain Traceability

a. When specified by contract, a supply chain traceability program in accordance with IPC-1782, or equivalent, shall [N1N2D3] be developed and maintained.

b. Duration of maintenance of records shall [N1N2D3] be as agreed between the Manufacturer and the User.

Trusted Source

When specified by contract, the Design, Manufacturing and/or Supply activities/entities (as applicable) shall [N1N2D3] be certified as a "Trusted Source" in compliance with IPC-1791.

Materials and Substances Declaration

When specified by contract, a Materials and Substances Declaration Plan in accordance with IPC-1751, or equivalent, shall [N1N2D3] be developed and implemented.