IEC PAS 62647-21:2011

IEC/PAS 62647-21 ®
Edition 1.0 2011-07
PUBLICLY AVAILABLE
SPECIFICATION
PRE-STANDARD
Process management for avionics – Aerospace and defence electronic systems
containing lead-free solder –
Part 21: Program management – Systems engineering guidelines for managing
the transition to lead-free electronics

IEC/PAS 62647-21:2011(E)
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IEC/PAS 62647-21 ®
Edition 1.0 2011-07
PUBLICLY AVAILABLE
SPECIFICATION
PRE-STANDARD
Process management for avionics – Aerospace and defence electronic systems
containing lead-free solder –
Part 21: Program management – Systems engineering guidelines for managing
the transition to lead-free electronics

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
V
ICS 03.100.50; 31.020; 49.060 ISBN 978-2-88912-600-2
– 2 – PAS 62647-21 © IEC:2011(E)

CONTENTS
FOREWORD . 4

INTRODUCTION . 6

1 Scope . 7

2 Normative references . 8

3 Terms and definitions . 9

4 Symbols and abbreviated terms . 11

5 General discussion of program management/systems engineering management

concerns . 11
5.1 Concerns in accordance to IEC/PAS 62647-1 (GEIA-STD-0005-1) . 12
5.1.1 Reliability . 12
5.1.2 Configuration control . 12
5.1.3 Risk management . 12
5.1.4 Detrimental effects of tin . 12
5.1.5 Rework/repair and maintenance . 13
5.2 Additional program management / system engineering concerns . 13
5.2.1 Cost . 13
5.2.2 Commercial off-the-shelf. 14
5.2.3 Quality . 14
5.2.4 Contractual language . 14
5.2.5 Program constraints . 14
5.2.6 System engineering management plan . 14
6 Requirements definition . 15
6.1 Customer requirements . 15
6.1.1 WEEE and RoHS Directives . 15
6.1.2 Executive Order 13148 (green initiative) . 15
6.2 Additional prime contractor requirements . 15
6.3 Change control . 15
7 Use environment(s) . 15
7.1 Impact on use environment(s) . 15
7.2 Impact on storage and transport . 15
8 Decision criteria . 15
8.1 Program decision concerning Pb-free . 15

8.2 Compliance to IEC/PAS 62647-1 (GEIA-STD-0005-1) . 16
8.3 Solder alloy chosen . 16
8.4 Other programs . 16
8.4.1 Percentages of product . 16
8.4.2 Supplier awareness . 16
9 Suppliers lead-free control plan . 16
9.1 Supplier procurement & subcontractor control . 16
9.1.1 Supplier procurement . 17
9.1.2 Supplier subcontractor control plan . 17
9.2 Productibility plan . 17
9.3 Manufacturing changes . 17
9.4 Manufacturing risk management . 18
9.5 Supplier schedule of Pb-free implementation . 18
10 Requalification / test plan . 18

PAS 62647-21 © IEC:2011(E) – 3 –

10.1 Delta qualification or requalification . 18

10.2 Acceptance by analysis / test . 18

10.3 Acceptance by similarity . 18

11 Rework / repair and maintenance . 18

11.1 Supplier recommendations for rework/repair of Pb-free products . 18

11.2 Maintenance and training documentation. 19

12 Risk management . 19

12.1 Program-level identification of program-level risks . 19

12.2 Risk analyses . 19

12.3 Risk mitigation . 19
13 Cost . 19
14 Presentation to customer . 19
14.1 Compliance to IEC/PAS 62647-1 (GEIA-STD-0005-1) . 19
14.2 System engineering management plan . 19
14.3 Other deliverables to the customer . 20
Annex A (informative) Matrix of tier level versus associated risk . 21
Annex B (informative) Links to the European Union Directives and Executive Order
13148 . 23
Annex C (informative) General program manager checklist for dealing with Pb-free
issues . 24
Annex D (informative) General manufacturing process assessment checklist for
assessing supplier compliance to IEC/PAS 62647-1 (GEIA-STD-0005-1) . 26
Annex E (informative) Recommended program language (subject to contractual
agreements) . 33
Bibliography . 34

– 4 – PAS 62647-21 © IEC:2011(E)

INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
PROCESS MANAGEMENT FOR AVIONICS –

AEROSPACE AND DEFENCE ELECTRONIC

SYSTEMS CONTAINING LEAD-FREE SOLDER –

Part 21: Program management –
Systems engineering guidelines for managing

the transition to lead-free electronics

FOREWORD
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is

indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
A PAS is a technical specification not fulfilling the requirements for a standard, but made
available to the public.
PAS 62647-21 © IEC:2011(E) – 5 –

IEC-PAS 62647-21 has been processed by IEC technical committee 107: Process

management for avionics.
The text of this PAS is based on the This PAS was approved for
following document: publication by the P-members of the
committee concerned as indicated in

the following document
Draft PAS Report on voting
107/130/PAS 107/138A/RVD
Following publication of this PAS, which is a pre-standard publication, the technical committee

or subcommittee concerned may transform it into an International Standard.

This PAS shall remain valid for an initial maximum period of 3 years starting from the
publication date. The validity may be extended for a single 3-year period, following which it
shall be revised to become another type of normative document, or shall be withdrawn.
This PAS is based on GEIA-HB-0005-1 and is published as a double logo PAS. GEIA,
Government Electronics and Information Technology Association, has been transformed into
TechAmerica Association.
This document is intended to be used in concert with IEC/PAS 62647-1 (GEIA-STD-0005-1)
and IEC/PAS 62647-2 (GEIA-STD-0005-2).
It should be noted that suppliers who have been qualified in compliance with
IEC/PAS 62647-1 (GEIA-STD-0005-1) and IEC/PAS 62647-2 (GEIA-STD-0005-2) and utilizing
IEC/PAS 62647-22 (GEIA-HB-0005-2) will have adequately addressed the concerns and
issues delineated in Clauses 5 through 14 of this PAS.

– 6 – PAS 62647-21 © IEC:2011(E)

INTRODUCTION
Due to a variety of real and potential health issues, many constituent materials used in the

production of electronic products have come under scrutiny. The European Union (EU) has

enacted two directives; 2002/95/EC Restriction of Hazardous Substances (RoHS) and

2002/96/EC Waste Electrical and Electronic Equipment (WEEE) that restrict or eliminate the

use of various substances in a variety of products that are produced after July 2006. One of

the key materials restricted is lead (Pb), which is widely used in electronic solder and

electronic piece part terminations. While these regulations may appear to only affect products

for sale in the EU, due to the reduced market share of the aerospace and high performance

industry in electronics, many of the lower tier Suppliers will change their products because

their primary market is consumer electronics. Additionally, several U.S. states have enacted
similar “green” laws and many Asian electronics manufacturers have recently announced
completely green product lines.
Since the aerospace industry is one of the few major industrial sectors that still repair Circuit
Card Assemblies (CCAs) and since Pb-free materials and processes are relatively immature
and poorly understood, an aerospace-wide approach to the transition was deemed to be
highly valuable.
PAS 62647-21 © IEC:2011(E) – 7 –

PROCESS MANAGEMENT FOR AVIONICS –

AEROSPACE AND DEFENCE ELECTRONIC

SYSTEMS CONTAINING LEAD-FREE SOLDER –

Part 21: Program management –
Systems engineering guidelines for managing

the transition to lead-free electronics

1 Scope
This PAS is designed to assist program management and/or systems engineering
management in managing the transition to lead-free (Pb-free) electronics to assure product
reliability and performance.
Programs may inadvertently introduce Pb-free elements (including piece part finish, printed
wiring board (PWB) or printed circuit board (PCB) finish, or assembly solder) if careful
coordination between buyer and Supplier is not exercised. For example, piece part
manufacturers may not always change part numbers to identify Pb-free finishes, especially if
the previous tin-lead (Sn/Pb) finished piece part has been discontinued. Detailed examination
of piece parts and documents at receiving inspection while crucial may not be sufficient to
identify Pb-free piece parts.
NOTE Pb-free technology can impact any program regardless of whether the program itself is exempt or bound by
environmental regulations. The industry conversion to Pb-free solder technology may affect an aerospace program
in one or both of the following ways:
1) if the program is required to implement Pb-free technology (contract requirement, environmental regulation,
etc), then the Program Manager/lead systems engineer will need to assess the impact of in-house transition
with respect to design (performance of products using Pb-free) and process (processes to build Pb-free
products);
2) if the program purchases COTS (Commercial-off-the-Shelf) items for its products/systems, then there is a very
good chance that these items will contain Pb-free solder or Pb-free finishes on parts, printed wiring boards
(PWBs), printed circuit boards (PCB), or circuit cards assemblies (CCA).
The basic principles delineated in this PAS can be used for program management and/or
systems engineering management of any aerospace and/or high performance program. The
annexes in the PAS describe tools that can be used in conjunction with this handbook.
1) Annex A describes a matrix of product tier level versus associated risks with respect to a
Pb-free transition.
2) Annex B contains links to the European Union Directives and Executive Order 13148.
3) Annex C contains a General Program Manager Checklist for Dealing with Pb-free Issues
that summarizes the content of this document.
4) Annex D contains a General Manufacturing Process Assessment Checklist to assess
Supplier compliance to IEC/PAS 62647-1 (GEIA-STD-0005-1).
5) Annex E describes recommended program language to assure performance, reliability,
airworthiness, safety, and certifiability of Pb-free product(s).
This PAS is designed to assist a program in assuring the performance, reliability,
airworthiness, safety, and certifiability of product(s), in accordance with IEC/PAS 62647-1
(GEIA-STD-0005-1). Please note that the Program Manager and systems engineer (along with
their respective organizations), and the appropriate enterprise authority work together in
ensuring that all impacts of Pb-free technology insertion are understood and risks mitigated
accordingly. Herein “Program Management (or Manager) and/or Systems Engineering
Management (or Manager) and/or the appropriate enterprise authority” shall be defined as
“Program Manager” throughout the remaining document (see Clause 3, Terms and
Definitions).
– 8 – PAS 62647-21 © IEC:2011(E)

2 Normative references
The following referenced documents are indispensable for the application of this document.

For dated references, only the edition cited applies. For undated references, the latest edition

of the referenced document (including any amendments) applies.

Industry Standards
IEC/PAS 62647-1,  Process management for avionics – Aerospace and defence
(GEIA-STD-0005-1), electronics systems containing lead free solder – Part 1: Lead-free

management
IEC/PAS 62647-2 Process management for avionics – Aerospace and defence
electronics systems containing lead-free solder – Part 2: Mitigation
(GEIA-STD-0005-2),
of the deleterious effects of tin
Performance Standard for Aerospace and High Performance
GEIA-STD-0005-1,
Electronic Systems Containing Lead-free Solder

GEIA-HB-0005-1, Program Management/Systems Engineering Guidelines For
Managing The Transition To Lead-Free Electronics
GEIA-HB-0005-2, Technical Guidelines for Aerospace and High Performance
Electronic Systems Containing Lead-free Solder
IPC-A-610, Acceptability of Electronic Assemblies
AS/EN/JISQ9100, Quality Systems – Aerospace – Model For Quality Assurance In
Design, Development, Production, Installation And Servicing
ANSI/ASQC Q9000  Quality Management and Quality Assurance Standards Guidance for
ARINC Project Lead-Free Soldering, Repair and Rework
Paper 671
PAS 62647-21 © IEC:2011(E) – 9 –

3 Terms and definitions
For purposes of this document, the following terms and definitions apply.

3.1
assemblies
are electronic items that require electrical attachments, including soldering of wires or piece

part terminations; examples include circuit card assemblies and wire harnesses.

3.2
COTS
is defined as “commercial off the shelf”. It can apply to a piece part, assembly, or unit.
3.3
critical
item or function, if defective, will result in the system’s inability to retain operational capability,
meet primary objective, or affect safety.
3.4
customer
refers to an entity or organization that (a) integrates a piece part, soldered assembly, unit, or
system into a higher level system, (b) operates the higher level system, or (c) certifies the
system for use. For example, this may include end item users, integrators, regulatory
agencies, operators, original equipment manufacturers (OEMs), and subcontractors.
3.5
High performance system or product
requires continued performance or performance on demand, or equipment down time cannot
be tolerated, or end-use environment may be uncommonly harsh, and the equipment must
function when required, such as life support or other critical systems
3.6
lead-free
is defined as less than 0,1 % by weight of lead in accordance with Waste Electrical and
Electronic Equipment (WEEE) guidelines
3.7
Lead-free Control Plan (LFCP)
refers to an aerospace or defence system Supplier’s document that defines the processes
that assure the plan owners, their Customers, and all other stakeholders that aerospace and
high performance high-reliability electronics systems containing Pb-free solder will continue to
be reliable, safe, producible, affordable, and supportable. An acceptable LFCP, per
IEC/PAS 62647-1 (GEIA-STD-0005-1), will fulfill all intentions of the standard. ANSI/ASQC
Q9000 documentation may provide a strong basis for the control plan. Technical guidance on
evaluating an adequate LFCP can be found in IEC/PAS 62647-1 (GEIA-STD-0005-1).
3.8
may
indicates a course of action that is permissible within the limits of this PAS, but not required.
3.9
Pb-free Tin
is defined to be pure tin or any tin alloy with < 3 % lead (Pb) content by weight. This means
that some Pb-free finishes other than pure tin, such as tin-bismuth and tin-copper, are
considered to be “tin” for the purposes of this handbook. Many of these alloys have not been
assessed for whiskering behavior.

– 10 – PAS 62647-21 © IEC:2011(E)

3.10
Pb-free tin finish
is defined to be Pb-free tin final finish or under-plate either external or internal to a piece part,

printed wiring board (PWB), printed circuit board (PCB), circuit card assembly (CCA) or other

hardware. This includes all leads and surfaces, even those coated, encapsulated, or

otherwise not exposed. It may include finishes on electrical piece parts, mechanical piece

parts, and printed wiring boards (PWB) printed circuit board (PCB) or circuit card assembly
(CCA). It does not include Pb-free bulk solders, assembly materials, ball-grid-array

terminations, or those devices where the Pb-free tin finish has been completely replaced.

3.11
PCB
stands for Printed Circuit Board, which is also commonly referred to as a Printed Wiring Board
(PWB)
3.12
piece part
is defined as an electronic component that is not normally disassembled without destruction
and is normally attached to a printed wiring board (PWB), printed circuit board (PCB) or circuit
card assembly (CCA), to perform an electrical function
3.13
program manager
for purposes of this PAS (and this PAS only), refers to program management (or manager)
and/or systems engineering management (or manager) and/or the appropriate enterprise
authority. The reason for this is to streamline this PAS. The implications are that the program
manager and systems engineer (along with their respective organizations) and the
appropriate enterprise authority work together in ensuring that all impacts of Pb-free
technology insertion are understood and risks mitigated accordingly.
3.14
PWB
stands for Printed Wiring Board, which is also commonly referred to as a Printed Circuit Board
(PCB)
3.15
repair
is the act of restoring the functional capability of a defective article in a manner that precludes
compliance of the article with applicable drawings or specifications.
3.16
rework
is the act of reprocessing non-complying articles, through the use of original or equivalent
processing in a manner that assures full compliance of the article with applicable drawings or
specifications
3.17
should
indicates that, among several possibilities, one is recommended as particularly suitable,
without mentioning or excluding others; or that a certain course of action is preferred but not
necessarily required; or that (in the negative form) a certain course of action is discouraged
but not prohibited.
3.18
sub-contractor
refers to an organization, within the given high-reliability industry, that supplies, maintains,
repairs, or supports electronic systems, and is not the direct Supplier to the Customer or user
of those systems
PAS 62647-21 © IEC:2011(E) – 11 –

3.19
supplier
refers to an entity or organization that designs, manufactures, repairs, or maintains a piece

part, unit, or system. For example, this includes original equipment manufacturers (OEMs),

repair facilities, subcontractors, and piece part manufacturers.

3.20
system
is defined as one or more units that perform electrical function(s).

3.21
tin whisker
is a spontaneous crystal growth that emanates from a tin surface. They may be cylindrical,
kinked, or twisted. Typically they have an aspect ratio (length/width) greater than two, with
shorter growths referred to as nodules or odd-shaped eruptions. See IEC/PAS 62647-2
(GEIA-STD-0005-2) for further description of tin whiskers and their physical attributes.
3.22
unit
is defined as one or more assemblies within a chassis to perform electrical function(s)
4 Symbols and abbreviated terms
ATP Acceptance Test Procedure
CCA Circuit Card Assembly
COTS Commercial Off-The-Shelf
ENIG Electroless Nickel/Gold
EU  European Union
FMECA Failure Mode Effects and Criticality Analysis
GEIA Government Electronics and Information Technology Association
IR  Infra-Red
LFCP Lead-Free Control Plan
OEM Original Equipment Manufacturer
OSP Organic Solderability Preservative
Pb-free Lead-Free
PMP Parts, Materials, and Processes
PWB Printed Wiring Board
PCB Printed Circuit Board
RoHS 2002/95/EC Restriction of Hazardous Substances
SEMP System Engineering Management Plan
SnPb Tin/Lead (normally 63 % tin / 37 % lead)
WEEE 2002/96/EC Waste Electrical and Electronic Equipment
5 General discussion of program management/systems engineering
management concerns
A Program Manager’s role is to be aware of how changes will affect the program, whether the
program is on the system level, unit level, assembly level, or piece part level. The change
from SnPb solder to Pb-free solder will affect all electronics programs, regardless of level or
size. The Program Manager also needs to understand where Pb-free is being introduced in
the program (piece part finishes only, assembly soldering, etc.) Annex A differentiates the

– 12 – PAS 62647-21 © IEC:2011(E)

various tier levels and the associated risk to consider. The following concerns need to be

considered for a successful transition.

5.1 Concerns in accordance to IEC/PAS 62647-1 (GEIA-STD-0005-1)

In accordance with IEC/PAS 62647-1 (GEIA-STD-005-1), program concerns include reliability,

configuration control, risk management, effects of tin in the system, and rework/repair and

maintenance.
5.1.1 Reliability
The program manager should understand how the transition to Pb-free may affect the

reliability of the program. The program manager or a designee should understand the effects
of mixing SnPb and Pb-free solder, effects on package types/geometry, how Pb-free may
react to the program’s use environment, if units and/or systems will include SnPb and Pb-free
assemblies, piece parts, etc. In addition, the Program Manager should consider a common
reliability data collection during all phases of the program to facilitate systems performance
improvement.
5.1.2 Configuration control
The need for configuration control is paramount to the Pb-free transition. Studies have shown
that mixing SnPb and Pb-free solders or the mixing of Pb-free solders of different alloys
and/or piece parts (solders or finishes of different alloys) may have detrimental impact on the
long-term reliability under high stress (e.g., military, commercial aerospace, or space)
environments. The program manager should understand the appropriate configuration
controls (e.g., traceability) that are necessary for the program’s environment. Note, the
program manager must decide the configuration control measures that must be taken for the
various levels (i.e., piece part, assembly, unit, system).
The material content of the terminations (component leads) is critical in assuring adequate
reliability and performance of finished product. The program manager should ensure that
appropriate and demonstrated processes are in place at suppliers that will accurately identify
the material content of piece parts used in soldered assemblies and that the material content
is compatible with the supplier’s soldering processes.
The program manager may require a parts, materials, and processes plan to be in place at
the supplier which reflects appropriate quality control procedures. the plan should include
sub-contractor controls that affect the reliability of the end product.
5.1.3 Risk management
Risk identification and risk assessment need to be performed for the Pb-free transition for the

particular environmental conditions of the program. Risks need to be identified early and a
mitigation strategy engaged. The Program Manager has a responsibility to conduct a
complete risk management plan.
5.1.4 Detrimental effects of tin
Pb-free tin finishes in an avionics or high performance system can have detrimental effects to
functionality of the system as tin whiskers can spontaneously grow from the surfaces. Piece
parts with Pb-free tin finishes have already been introduced into aerospace and high
performance systems with minimal understanding of the effects that it will have. Program
Managers need to have a plan for either eliminating use of Pb-free tin in their
product, through life-time buys or re-finishing piece parts, or a plan for addressing and
mitigating the risks.
IEC/PAS 62647-2 (GEIA-STD-0005-2) provides standard methods for controlling and
mitigating the use of Pb-free tin finished piece parts. It defines three basic levels, with

PAS 62647-21 © IEC:2011(E) – 13 –

additional sublevels, for controlling and mitigating the use of Pb-free tin finishes with accurate

regard to tin whiskers. These levels can be summarized as follows.

Level 1. No restrictions on Pb-free tin finish use.

Level 2. Pb-free tin finish is allowed under some circumstances.

– Level 2A. Use of Pb-free tin finish without explicit controls is acceptable under

most circumstances but the likelihood of whiskers and methods used to

estimate their impact and mitigation strategies will be documented. Pb-free tin

finish may be prohibited in some specific circumstances called out in

contractual documents.
– Level 2B. Pb-free tin finishes may be used but only with Customer approved

and specified control measures. These Pb-free tin finish approvals may be
blanket approvals for multiple piece parts and applications within the system.
Pb-free tin finish may be prohibited in some specific circumstances called out in
contractual documents.
– Level 2C. Restricted use of Pb-free tin finish. Pb-free tin finish is prohibited
unless an exception with Customer approval is made. Specific instruction on
use of Pb-free tin finish and required control measures to be provided and
reviewed on a case-by-case basis.
Level 3. Use of Pb-free tin finish is prohibited and measures must be taken to verify
compliance.
These levels are designed to be used in requests for proposals and control documents. The
Customer should determine the appropriate control level or levels for their product, based on
criticality, their comfort with the risk, and other mitigating features of their program, such as
redundancy and repairability. For many larger programs, different subsystems or units may
need different control levels that can be based on Customer and Supplier discussions and
agreement regarding both application and Supplier mitigation solution knowledge.
In most cases, it would be appropriate for OEMs to have general policies that aid in the
selection of the appropriate control level. Program Managers should work with their
companies to develop the policy to aid in consistent requirements across programs.
Program Managers also need to be prepared for handling errors in finish determination or
mitigation application. This may simply be a variation in the program's normal process waiver
process or may require a more in-depth risk assessment, depending on the criticality level.
5.1.5 Rework/repair and maintenance
Rework/repair and maintenance becomes a concern if SnPb and Pb-free solders and/or piece
parts are used on the same assemblies. As stated before, studies have shown that reliability

of the joints/junctions of mixed lead and Pb-free solder may decrease in high stress
environments. A Program Manager should make the Customer aware of the higher risks
associated with field rework/repair and maintenance when standard solder materials (i.e.
60 % tin/40 % lead or 63 % tin/37 % lead) are used on Pb-free assemblies and/or piece parts.
5.2 Additional program management / system engineering concerns
The Program Manager also has additional concerns from a programmatic point of view. These
include cost, parts obsolescence, COTS, quality, contract language, other existing program
constraints, updating of the program System Engineering Management Plan (SEMP). Other
concerns can be addressed based on specific program needs.
5.2.1 Cost
The costs of the Pb-free transition need to be quantified and decisions need to be made as to
who will assume the costs. The Program Manager should be aware that the situation is likely
to be dynamic over the next several years. Added costs may come from additional risk

– 14 – PAS 62647-21 © IEC:2011(E)

management determination, configuration controls, rework/repair and maintenance changes,

drawing changes, possible redesign, re-qualifying/delta qualifying, etc.

5.2.2 Commercial off-the-shelf

Commercial-off-the-shelf (COTS) is always a critical concern for a Program Manager. The

very nature of COTS may allow Pb-free substitution irrespective of program requirements.

5.2.2.1 COTS piece parts and parts obsolescence or COTS piece parts

The Supplier may request substitution of Pb-free finished piece parts on a program. This
occurs not only because of the piece part Supplier obsolescing standard SnPb-finishes, but

also due to a COTS piece part substitution. The Program Manager or a designee should have
controls in place and understand IEC/PAS 62647-2 (GEIA-STD-0005-2), to mitigate the risks
associated with Pb-free finished piece parts and COTS. The Program Manager needs to
ensure that the parts, materials, and processes (PMP) control plan for the program is updated
and addresses how lead-free piece parts will be identified and tracked. If a PMP control plan
is not available for the program, the Program Manager should ensure that the PMP functional
group is aware of each parts substitution and is adequately addressing the issue of lead-free
piece parts.
5.2.2.2 COTS assemblies
The product may contain COTS assemblies, as well. The Program Manager should be aware
of the possible risks due to COTS assemblies containing either Pb-free piece parts and/or Pb-
free soldered assemblies. The Program Manager needs to ensure that the parts, materials,
and processes (PMP) control plan for the program is updated and addresses how lead-free
assemblies will be identified and tracked. If a PMP control plan is not available for the
program, the Program Manager should ensure that the PMP functional group is aware of each
parts substitution and is adequately addressing the issue of lead-free assemblies.
5.2.3 Quality
Quality is a critical consideration in the transition to Pb-free and the Program Manager needs
to be assured that the final product meets the technical and operational requirements with the
specified reliability at all levels (reference IPC-A-610 and/or AS/EN/JISQ9100 depending on
the program requirements). This includes flow of requirements, implementation and
documentation through and to subcontractors.
5.2.4 Contractual language
Appropriate contractual language needs to be included in new contracts that describe the
Customer requirements regarding Pb-free parts. Example contractual language is included in

Annex E.
5.2.5 Program constraints
The Program Manager needs to be proactive in understanding all of the impacts to the
program schedule (including all integrated master schedule line items). Consideration needs
to be particularly paid to changes in the delivery schedule due to requalification/delta
qualification of Pb-free parts and additional reliability testing. Also, if risk mitigation plans
include lifetime buys of long-lead SnPb-finish parts (due to obsolescence), the updated
schedule needs to reflect the changes appropriately.
5.2.6 System engineering management plan
The Program Manager should reassess the program’s system engineering management plan,
if one exists, and update to include the Pb-free transition controls for the program.

PAS 62647-21 © IEC:2011(E) – 15 –

6 Requirements definition
A re-evaluation of the program requirements should be performed to determine the impact of

the Pb-free transition.
6.1 Customer requirements
The Program Manager should include all of the Pb-free transitions in a thorough risk

assessment/mitigation plan and present it to the Customer. The purpose of the plan is to help

the Customer understand the risks associated with the transition.

6.1.1 WEEE and RoHS Directives
The Program Manager should understand the implications of the WEEE and RoHS directives
(Annex B).
6.1.2 Executive Order 13148 (green initiative)
Even though this generally applies only to facility operations issues, weapon system
maintenance by the Customer may come under this category. The Program Manager should
be aware of the Customer’s requirements in this area (Annex B).
6.2 Additional prime contractor requirements
Additional prime contractor requirements need to be re-assessed with regard to a possible
Pb-free transition.
6.3 Change control
The Program Manager should determine if any change from SnPb to Pb-free constitutes a
change for which Customer approval is needed. The purpose is to assure that configuration
control, traceability, and marking are properly controlled.
7 Use environment(s)
7.1 Impact on use environment(s)
The use environment(s) is defined by the program requirements. The Program Manager
needs assurance from the Supplier that the transition from SnPb to Pb-free solder will not
impact reliability of the product in the use environment. The consideration here is whether or
not Pb-free solder will behave differently than SnPb solder in the use environment.

7.2 Impact on storage and transport
The Program Manager or a designee should evaluate the storage and transport requirements
with respect to any Pb-free implementation. The impact of SnPb versus Pb-free solder on
long-term storage or transport environment could be significant and needs to be evaluated as
part of the risk management plan.
8 Decision criteria
8.1 Program decision concerning Pb-free
The Program Manager must choose whether or not any Pb-free will be accepted. This
decision should be based on Customer feedback, risk analyses, system engineering analyses,
and Supplier information. Annex C describes a checklist for the Program Manager to use for
ascertaining the effects of a Pb-free transition to the program.

– 16 – PAS 62647-21 © IEC:2011(E)

8.2 Compliance to IEC/PAS 62647-1 (GEIA-STD-0005-1)

The Program Manager or a designee should require a Supplier to show compliance to

IEC/PAS 62647-1 (G
...