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15 september 2005 page 1/31

44th CEEES Meeting

Minutes of R and ESS WG

Meeting location : Hotel NOVOTEL Paris

Date : 24th October 2005

Attendees : see list hereafter


Name

1st

name

Company/Society phone

fax email

RUDING Gunnar Ass. of Swedish Engineering

Industries /SEES

46 8 653 0418 46 8 653 0419 [email protected]

GRZESKOWIAK

Henri MBDA F /ASTE +33 1 34 88 35 23 +33 1 34 88 34 75

[email protected] office

[email protected] home

HOLY

Michel retired/SSEE +41 1 865 46 68 [email protected]

PALMEN Helge VTT Industrial Systems /SEEF +358 9 456 56 31 +358 9 456 7042

[email protected]

PEREGO Marco Angelantoni Industrie SPA +39 075 8955 213 +39 075 8955 200 [email protected]

WEETCH Colin e2v Technologies/SEE + 44 1245 453654 [email protected]


1 - ADOPTION OF THE 43rd

CONGRESS R&ESS MEETING MINUTES

The minutes are adopted.

2 - Apologies FOR ABSENCES

No.

3 - INTRODUCTION OF NEW MEMBERS

No new member.

5- ESS ACTIVITY

It was agreed that there is a need for a basic terminology of terms relative to the tests , environmental

engineering and reliability such as MTBF, MTTR, reliability test, accelerated test ….

It was proposed that all the members send a list of these terms , with the known definitions and

corresponding source, to Marco , that will arrange a digest of all these inputs for next meeting.

Michel has proposed a list ( see in attachment 1). This list has been examined during the meeting.

Durability : HG will provide next time the definition (adopt the definition of the IEC56) ; as it is related

to the cost, is it affiliated to the life cycle cost ? Refer to the IEC 56.

Michel Holy wonders if there is a Mathematical relation between Reliability and Maintnability ?

Helge will examine the compatibility between the proposed terminology and IEC one.

HG will provide return from reliability and statistician collegues on mathematical description.

Michel Holy will provide quick definitions of abbreviations. He is requesting to verify that the structure

of the terms is complying with the content of the definition of the related terms.

6- R ACTIVITY

7-

6.1 Life cycles environmental profile

It has been also decided in London to work of the product life cycles .

Extract from London meeting report : “

• The expected life profile of a product in different sectors of activity *, which is an important

issue to consider in product sustainability growth

o Output : life cycle environmental profile characterisation : climatic related parameters

such as number of cycles, temperature range , rate of change , humidity, pressure if

relevant, chemical contaminents , etc.)

or mechanical related parameters such as PSD for vibration, SRS or time histories for

shock, etc.

• Operational use :

o Dormant periods ( storage)

o Functional activation( ON/OF, junction temperature elevation, electrolytic

phenomenon,etc.)

• Identify the expected processes or modes of failure

• Assess the life duration of different type of technologies

*The sectors of acitivity covered by the current members are : mobile phones, telecommunication,

automation/robotics, nuclear power plant, control of climatic chambers, electronics in automotive

industry, missiles.”

Henri is proposing as a beginning to consider the following documents in which there are elements on life

cycle profile description:


- French CIN EG 1 “ Taking into account the Environment through a

product development ( see an English version as attached document)

- An example of life cycle description ( see a french version as attached

document )

- Hank Caruso fundamental paper on LCEP , presented at IEST ( distributed during the current

meeting) .

- Henri has evocated the Strength / Stress approach ; the general appendix of GAM EG 13 is

describing this approach in one appendix ( see annex 14 of General Appendix of GAM EG 13 in

French , attached to the meeting report , in French)

Henri has also introduced a document dedicated to program management structuration : EN 9200 .

The work will be continued on the example of life cycle description on the mobile equipment dedicated to

pollution measurement.

6.2 Different types of tests

6.2.1 List of withhold tests

Type of test In charge of

feasability , design aid Colin Done : see att.3

Development test Michel

Reliability growth test (RGT) Collin

Aggravated tests Henri Done : see att.4

Accelerated tests Helge

Qualification Aad *

Reliability demonstration Collin

ESS including HASS Bob for ESS

( Henri for

HASS)

Acceptance test Bengt *

Production reliability acceptance test (PRAT) Bob

Pre production (zero production) Gunnar

Life duration Collin

Verification (validation) Bengt *

* to be confirmed

6.2.2 Template to apply to each of these tests

1 Test objective (purpose,definition…)

2 What is driving you for performing the test ?

3 Level of assembly of the product submitted to test

4 Number of items submitted to test

5 Type of product relevant to be submitted to the test ( mass volume low price product ,..)

6 Test duration (days, weeks, months..)

7 Separate or combined environments

8 Product strength and environment stress variabilities are or aren’t considered

( in the process of deriving the test severity)

9 Does the test bring knowledge on reliability parameters ?

10 Does the test consume totally or partially the life potential ot the equipment submitted to test ?

11 main norms , standards, technical references relative to this type of tests

For next meeting : the proposed persons will try to apply the template to the corresponding test .


Accelerated tests by Helge Palmen ( see attachment 4)

Accelerated stress (Objective : identify product weaknesses by stimulation ) and accelerated life testing

(simulation of the field stresses) : a long discussion has taken place in order to clarify the differences

between the 2 types of tests. Helge will try to fill the ablove template for the 2 tests in order to clarify the

differences. There are still unexpected statements as Helge considers that stimulation ( in the

accelerated stress approach) may be established using models. That is not normally the case ( see the §

on aggravated tests = highly accelerated tests in attachment 3).

ESS and highly accelerated tests ( such as HALT) are not affiliated to the family of “Accelerated tests”

because acceleration in this latter family is based on a failure model making the relation between an

excitation and the expected failure . That is not the case in the highly accelerated tests.

Henri G. has indicated that there are 2 type of accelerated tests :

The first one is based on a physical model on the failure ( such as 5th power law)

The second is based on statistical description of the failure occurrence , with laws distribution such as

Weibull , where an acceleration factor is one parameter .

The 2 types of accelerated tests must be described. HG will make a proposal for the next time.

Development tests by Michel Holy (see attachment 5)

To be seen next meeting

6.3 CEN WG10/EG8

Next meeting :

the § “ review and comparison of environmental management standards” page 39 and

following will be discussed

recommendation for a future work : page 29 ( to confirm)

first part of DEF STAN 0035 and CIN EG 1 ( in English) will be discussed

7- MISCELLANEOUS

- Collin : European Legislation on reducing and/or eliminating lead, cadmium , mercury and

some flame retardants comes into force in July 2006. Collin is making the following 2 parts

proposal :

o The first proposal is for each member of the R and ESS WG. To comment on how

industry in each member country is interpretting and applying the rules of the

legislation

The second proposal is the procurement of lead free components . Are there issues with

reliability ?

- Gunnar arose the subject “ Risk taking relative to guarantee matters” and taking of insurance

in case something goes wrong. He considers that the subject is becoming more serious in the

current context :

o More Virtual testing

o Shorter development time induces shorter testing duration

- Michel Holy points out the fact that the product manufacturer should be responsible in case the

rules of the current state of the art haven’t been followed.See IEC 56 to see if these aspects are

treated.


8 TOUR OF TABLE

- Colin

60 persons are trained each year by Cranfield/SEE courses in UK

membership has dobbled this year after the campaign

- Gunnar : Unusual number ( 58 , usually 25 ) of participants to a workshop called “ The

breaking point” ; the breaking point is where the virtual testing is taking over from the physical

testing. Exemples were given of electronics designed and tested virtually and brought directly

to the market. We are in fact at the point where the virtual testing plays an increasing role (

50% ? ) and where the physical tests that remain are those which are still necessary.

Programme in English will be sent by Gunnar if available.

- Marco :

o A course on explaining concerns with statistic, uncertainty in the environmental

field

o Sponsoring in march the course of Tustin with LDS

- Helge : project development mechanical and electronic structures for transportation, installation

and use ; 2 or 3 subprojects are defined. Thermal, mechanical , ( EMC ?) all aspects will be

considered. This project will combine previous results achieved in previous projects. It must

help in the design of the products.

- Michel Holy

o The workshop on how to specify the environmental conditions was postpone to

next year

- Henri

o The ASTE guide on ESS based on highly accelerated tests is finished ; see

summary in appendice 7.


List of virtual members

Current members + following list.

TOOLA Arja NOKIA +358 40 7685072 [email protected]

BODIN Hakan LabTest ? [email protected] ?

STREUBEL Reinhard BGT 49 7551896276 49 7551 892163 [email protected]

TURTOLA Antti KOTEL 358994565639 [email protected]

VAN DORP

Aad National Aerospace

Laboratory

+31-527-248457 +31-527-248210

[email protected]

TURTOLA Antti KOTEL 358994565639 35894567042 [email protected]


Definition(s) of Terms Dedicated to Availability, Reliability & Maintainability

1) Terminology-Structure

Environment Stress has direct influences on "Reliability" and "Maintainability"

2) Terms of Reliability and their abbreviations

- Reliability Function R(t)

- Failure Rate λ(t) - Mean Time Between Failures MTBF - Mean Time To Failures MTTF - Mean Time To Mission - Failures MTTFM - Lifetime TL - Life Cycle LC - Mission Profile MP - Life Environmental Cycle Profile LCEP


Durability: capacity of a functional unity to execute a function required in definite conditions of use and

of maintenance till his(its,her) end of useful life or until what it does not agree any more for economical

or technological reasons (ref: Reliability, Maintenabilité and Availability - October, 1993).

- Dependability: together capacities of a product allowing it to arrange functional specified

performances, at the deliberate moment, during duration foreseen, without damage for itself and for its

environment (ref: BNAE RG Aéro 00040).

2.1) Relations between the terms of Reliability

∞

MTTF = ∫R(t)•dt (for Lifetime = ∞)

0

for a finite Lifetime the upper limit of the integral is TL

λ(t) = d R(t) / R(t) •dt

This equation shows that the reliability function R(t) is completely defined by the failurerate λ(t) .

With R(0) = 1, the reliability function reads as follows:

t

- ∫ λ(x) dx

R(t) = e 0

For λ(t) = λ = constant it follows:

∞

R(t) = e- λt

and in this case is MTTF = ∫e- λ(t) dt =1/λ

0

2.2) Terms related to Reliability

Reliability - Analysis - Blockdiagramm - Requirements - Verification - Program - Improvement - Assurance of - Evaluation - Of mechanical Items


Failure - Failure Analysis - FMEA (Failure Mode And Effects Analysis)

- FMECA (Failure Mode, Effects and Criticality Analysis) - Failure Cause - Failure Mode - Failure Symptom - Failure Criticality - Failure Effect - Failure Detection - Failure Localisation - 8D process

Fault - Specification-fault - Engineering-fault - Manufacturing-fault - Using-fault

Reliability Improvement during

Engineering - R-Verification - R-Analysis - R-Test

- HASS (Highly Accelerated Stress Screening) - HALT (Highly Accelerated Life Testing)

- R-Demonstration

Manufacturing - ESS

- Qualifications-Tests

Product Use - Reliability Growth

3) Terms of Maintainability and their abbreviations

Is there any mathematical presentation of the following terms ?

- Maintenance

- Preventive Maintenance

- Mean Time To Preventive Maintenance MTTPM : no mathematical presentation (i.e. :

valeur moyenne observée)

- Time Between Preventive Maintenance TBPM : no mathematical presentation (i.e. : valeur

moyenne observée)

- Maintenability : Capacity of a product to be put back(handed) in a state of given functioning, in a

specified limit of time (t), when the work is made according to prescribed procedures and given

conditions. This capacity can be translated in the term of probability M (t).


- Corrective Maintenance

- Mean Time To Repair : MTTR

- Repair Rate µ(t) : Conditional probability that the repairation of a failing product is realized on

an unit of time given from moment t, knowing that it was still not it to t.

3.1) Relations between the terms of Maintainability

to be defined

- µ(t) = d M(t) / M(t) dt (M(t) = maintenability)

- MTTR = = ∫M(t)dt

3.2) Terms related to Maintainability

- Maintainability - Analysis

- Requirements - Verification - Program - Improvement - Assurance of - Evaluation

4) Definitions for Systems and/or Hardware

Functionality

[2] The capability of a product to provide the required function when it is used under specified

conditions.

Operational Availability; Point Availability

[1] Probability that a product will perform its required function under given conditions at a stated

instant of time.

Safety

[1] Ability of a product to cause neither injury to persons, nor significant material damage or other

unacceptable consequences

Remark:

Safety is subdivided into accident prevention (the product is safe working while it is operating

correctly) and technical safety ( the product has to remain safe even if a failure occurs)


[3] State in which the risk of harm (to persons) or damage is limited to an

acceptable level

Note 1: Safety is one of the aspects of Quality

Note 2: The above definition is valid for the purposes of quality standards. the term "safety" is

defined differently in ISO/IEC Guide 2

Usability

[2] The capability of a product to be understood, learned, used and efficient for the user, when used

under specified conditions.

Operational Effectiveness

Logistical Support

[1] All activities undertaken to provide effective and economical use of an product during ist

operating phase.

Maintainability

[1] Probability that preventive maintenance or repair of an item will be performed within a stated

time interval for given procedures and resources.

Remark:

A qualitative definition is:

Ability of a product to be retained in or restored to the ability to perform its required function in a

given time interval under stated procedures and resources.

Maintainability is subdivided in serviceability (preventive maintenance) and reparability (corrective

maintenance or repair)

Useful Life

[1] Total operating time of a product, ending for a nonrepairable product when the failure probability

becomes too high or the product functionality is obsolete, and for a repairable product when the

intensity of failures becomes unacceptable or when after a failure the product is considered to

be no longer repairable.

Remark:

The term "Life Time" is only used for nonrepairable products. It is the time span between initial

operation and failure of a nonrepairable item.


Reliability

[1] Probability that a product will perform is required function under given conditions for a stated

time interval.

Remark:

This does not mean that redundant parts may not fail. Such parts can fail and be repaired.

Defect (only used for software)

[1] Nonfulfillment of an intended usage requirement or reasonable expectation, essentially present

at t=0

Remark:

From a technical point of view, a defect is similar to a nonconformity, however not necessarily

from a legal point of view. Defects do not need to influence the item's functionality. They are

caused by flaws (errors, mistakes) during design, production, or installation. Unlike failures,

which always appear in time (generally randomly distributed), defects are present at t=0.

However, some defects can only be detected when the item is operating and are referred to as

"dynamic defects". Similar to defects, with regard to the cause, are systematic failures; they are

not necessarily present at t=0

[3] Nonfulfillment of an intended usage requirement or reasonable expectation, including one

concerned with safety

Note: The expectation must be reasonable under the existing circumstances.

Defect- Immunity) (only used for software)

[2] The capability of the Software product to maintain a level of performance when used under

specified conditions

Note:

Wear or ageing does not occur in software. Limitations in "reliability" are due to faults in

requirements, design, and implementation. "Failures" due to these faults depend on the way the

software product is used and the program options selected rather than on elapsed time.

Supportability, Maintainability ( for software)

[2] The capability of the software product to be modified. Modifications may include corrections,

improvements or adaptation of the software to change in environment, and requirements and

functional specifications.


Security

[2] The capability of the Software product to protect information and data so that unauthorised

person or systems cannot read or modify them and autorised persons or systems are not

denied access to them.

Failure

[1] Termination of the ability of an item to perform a required function under specified conditions.

Dependability

[1] Collective term used to describe the availability performance and its influencing factors, such as

reliability performance, maintainability performance, and logistical support performance

[3] Collective term used to describe the availability performance and its influencing factors, such as

reliability performance, maintainability performance, and logistical support performance

Note 1: Dependability is used only for general descriptions in non-qualitative terms

Note 2: Dependability is one of the time-related aspects of quality

Note 3: the definition of dependability and note 1 given above are taken from IEC 50(191),

which also includes related terms and definitions.

Functionality ( Capability, Technical Performance)

(1) Ability of an item to meet a service demand of stated quantitative characteristics under given

conditions

(2) The capability of a product to provide the required function when it is used under specified

conditions.

Referenced Documents

[1] A. Birolini, Quality and Reliability of Technical Systems

Springer- Verlag

[2] ISO/IEC 9126-1, Software Engineering - Product Quality Part 1

[3] EN ISO 8402 Quality management and quality assurance - Vocabulary


1.0 What is a Feasibility Study?

A feasibility study is designed to provide an overview of the primary issues related to

a technical and business idea. The purpose is to identify any "make or break" issues

that would prevent the test from being successful. In other words, a feasibility study

determines whether the technical issues make sense, as well as the business issues

but I am concerned with technical issues here.

A thorough feasibility analysis provides a lot of information necessary for the

technical plan. For example, a good market analysis is necessary in order to

determine whether the project is feasibility. This information provides the basis for the

market section of the business plan.

Because putting together a technical and business plan is a significant investment of

time and money, you want to make sure that there are no major roadblocks facing

you when the test plan is finalized and you make the investment in time and

equipment. Identifying such roadblocks is the purpose of a feasibility study.

A feasibility study looks at three major areas:

1. Market issues (Not dealt with)

2. Organizational/technical issues

3. Financial issues (Not dealt with)

Again, this is meant to be a "first cut" look at these issues. For example, a feasibility

study should not do in-depth long-term financial projections, but it should do a basic

break-even analysis to see how much revenue would be necessary to meet your

operating expenses.

The purpose of the business plan is to minimize the risk associated with a new

business and maximizes the chances of success through research and maximizes

the chances for success through research and planning.

(cf. University of California)

Technological Issues

The cost and availability of technology may be of critical importance to the feasibility

of a project, or it may not be an issue at all.

For example, a service organization, such as a childcare centre, will have a few

equipment and other technology- related issues to address. A manufacturing


enterprise, on the other hand, may have a number of complex technology questions

to analyze in order to determine whether or not the business is feasible.

Key questions to answer include:

a. What are the technology needs for the proposed business?

b. What other equipment does your proposed business need?

c. Where will you obtain this technology and equipment?

d. When can you get the necessary equipment?

How does your ability to obtain this technology and equipment affect your start-up

timeline?

e. How much will the equipment and technology cost?

Keeping in mind that technology doesn't necessarily mean complex machinery; if

your business simply needs a personal computer, printer, and fax machine, those are

your technological needs.

However, making wise decisions on even simple purchases such as office machines

may require some research. Obviously there are numerous types of personal

computers on the market. You many want to check Consumer Reports for their

recommendations, do some comparative shopping, and ask acquaintances about

their experiences with different companies. Your cost estimates will get plugged into

your financial projections.

Naturally, the more complex the technology you need, the more research that will be

required to make good decisions about it. This is important and should not be looked

at trivially.

Feasible:

“an examination of a situation to decide whether a suggested method, plan or piece

of work is possible or reasonable”.

Feasibility: noun {U}

Whether something is feasible:

"People who consider only price, and not value, are the lawful prey of those who

purvey shoddy goods" John Ruskin (1819 - 1900)

2.0 The Technical Issues to Look at During the Feasibility Study


In the commercial market we have to decide what we trying to achieve

with a certain test. The main thrust is always the reliability of the

product being manufactured.

The product life cycle begins at the component level and continues through assembly

level; the life cycle includes exposure to the following environments

Assembly/process

Testing

Storage

Transportation

Operating

Servicing ( preventive and corrective maintenance)

2.1.1 Assembly/Process

During processing and assembly of electronic assemblies, temperature excursions

take place, e.g. soldering including reflow, cleaning or imposed thermal cycling tests.

These temperature excursions can be damaging to some parts of the assembly and

consume some part of the available life. This damage should be minimized by

keeping the number of excursions to a minimum and the damage needs to be

considered in the overall reliability estimates.

2.1.2 Testing

When devising the overall reliability test plan the frequency of applied test to the

device and the fatigue that the testing induces into the product will be identified.

2.1.3 Storage

Storage tests will be defined by the product specification. The storage life of the

product will be identified which may range from a few months to many years. A

storage life cycle may include storage in a mobile unit to storage in a temperature-

controlled warehouse.

2.1.4 Transportation

Transportation is not a single event that is simply defined. Each vehicle type may

impose unique environmental loads. Each may also provide protection from certain

environmental conditions. Duration and frequency of occurrence will influence how


environmental effects are accumulated over time. The

transportation configuration and degree of loading can also

affect the loads imposed on the product.

2.1.5 Operating

It is assumed that the operational characteristics will not affect the reliability test as

the unit is a low power device and operational tests.

2.1.6 Environmental Stress Screening (ESS)

ESS has the potential to identify latent defects that may cause early failures in a

product. ESS needs to be specifically designed to accelerate the failure of 'weak'

elements in the assembly. ESS does not add to the number of such failures but

causes them to occur in a significantly shorter period of time.

Effective ESS programmes should be supported by well planned `Root Cause

Analysis' (RCA) and corrective action resources. These enable timely corrective

actions, elimination of latent defects and ultimate removal of the ESS process subject

to continued monitoring and control of the manufacturing process.

3.0 Conclusion

All the above tests will be scrutinized during a feasibility study, equipment,

infrastructure human resource and all the associated cost that go with these

requirements.

This is the first part in looking at a reliability test programme.

Colin Weetch

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cop

y, tu

rns o

ut eff

ective to r

eve

al th

e e

xis

tence

of

the r

ele

vant ca

use o

f defe

ct and

po

wer

so to

corr

ect

it.

- 2

-nd c

ase:

the r

ele

va

nt ca

uses o

f fa

ilin

g

pre

sum

ed c

an a

ffect a p

riori o

nly

a w

eak f

raction o

f th

e

com

ple

te p

op

ula

tion o

f th

e p

roduct (f

or

exam

ple

: le

ss

than 5

% o

f th

e p

opu

lation).

In th

at case,

it is n

ot

very

pro

ba

ble

tha

t a lim

ited n

um

ber

of

AG

GR

AV

AT

ED

TE

ST

S a

llow

s t

o r

eve

al th

is r

ele

van

t cause.

As

exam

ple

, th

e u

se o

f th

e m

odel bin

om

ial in

dic

ate

us tha

t

if o

ne h

opes t

o r

evea

l a

n r

ele

vant

cause o

f fa

iling

aff

ecting o

nly

5 %

of

the p

opula

tion w

ith a

pro

bab

ility

of

the s

uccess o

f 80 %

, it w

ou

ld b

e n

ecessary

to

subje

ct

abou

t 30

copie

s to t

he t

est

of

AG

GR

AV

AT

ED

TE

ST

S.

Such q

ua

ntity

is tota

lly inco

mpatible

with

the

im

pera

tive

manufa

ctu

rers

. C

onsequen

tly,

the A

GG

RA

VA

TE

D

TE

ST

S r

ealiz

ed in th

e p

hase o

f conception /

develo

pm

ent on a

n a

lwa

ys v

ery

lim

ited n

um

ber

of

copie

s c

an

not

ha

ve a

gre

at eff

icie

ncy to

ward

the

revea

ling o

f th

is t

ype

of

defe

cts

. O

nly

, a

ggra

vate

d E

SS

(HA

SS

) in

the

ph

ase o

f pro

ductio

n w

ill b

e s

usceptible

to r

evea

l, in a

dd

itio

n t

o th

e m

anufa

ctu

ring d

efe

cts

,

these d

efe

cts

of

the c

oncep

tion

wh

ich w

ould

aff

ect only

a w

eak f

raction o

f th

e p

rod

ucts

durin

g th

eir p

rofile

of

life.

15

se

pte

mb

er

20

05

pa

ge

21

/31

With r

egard

to

the

obta

inin

g the

lim

its o

f fu

nction

ing

and /

or

of

destr

uction o

f th

e p

rod

uct, th

e m

ajo

r

difficulty p

laces its

elf in th

e s

tatistica

l chara

cte

r

associa

ted

to t

hese s

izes.

So, th

e o

bta

inin

g in a

diffe

rent w

ay g

iven v

alu

e o

n the

lim

it o

f fu

nctionin

g th

e

sin

gle

cop

y d

oes n

ot re

vea

l in

evitab

ly th

e c

entr

al va

lue

of

the s

tatistical dis

trib

utio

n o

f th

is lim

it w

hic

h c

ould

be

associa

ted

to a

n im

port

ant

popu

latio

n o

f th

e t

este

d

pro

duct. I

n p

art

icu

lar,

this

unit e

xperim

enta

l va

lue c

an

be a

va

lue o

f ta

il of

dis

trib

ution,

pla

ced t

o th

e left

or

to

the r

ight

of

the d

istr

ibution.

It p

roves w

hy it is

hard

ly

recom

mended,

when it

is c

om

patible

with th

e

impera

tives o

f develo

pm

ent, to m

ake the

AG

GR

AV

AT

ED

TE

ST

S o

n s

evera

l cop

ies a

nd n

ot o

n

the s

ingle

unity. T

he n

um

ber

of

ava

ilab

le c

op

ies b

ein

g

alw

ays v

ery

lim

ited in t

he p

hase o

f de

ve

lopm

ent; o

ne

can c

onsid

er

that a n

um

ber

of

unitie

s w

hic

h a

re a

ble

to

go f

rom

3 to 5

esta

blis

h a

n a

ccepta

ble

com

pro

mis

e.

5

Typ

e o

f pro

duct re

leva

nt to

be s

ubm

itte

d t

o th

e test (

mass v

olu

me lo

w p

rice p

roduct ,..)

1.

Facto

rs b

ou

nd

in

co

sts

an

d in

th

e s

trate

gic

co

nte

xt

"

Str

ate

gic

aspects

bo

und(c

onnecte

d)

to t

he

mark

et (e

x: an

y ri

gh

t fo

r th

e e

rror

from

the lau

nch o

f th

e

firs

t copie

s o

n t

he m

ark

et, m

atu

rity

of

the p

roduct fr

om

the s

tart

ing,

…)

"

The im

pera

tives o

f re

ducin

g the

costs

of

resum

ption o

f th

e d

efe

cts

of

conception

"

The im

pera

tives o

f re

ducin

g the

tim

es o

f

develo

pm

ent

"

The im

pera

tives o

f re

ducin

g the

dura

tio

ns o

f

15

se

pte

mb

er

20

05

pa

ge

22

/31

ES

S

"

Als

o a

pp

lica

ble

in c

ase o

f chang

e o

f

techno

log

ies if

conditio

ns o

f use a

re c

orr

espond

ing to a

light e

nvironm

ent

"

Hig

h m

ass p

roduction w

ith

weak e

nvironm

enta

l

conditio

ns

"

off

the s

helf e

qu

ipm

ent sub

mitte

to lig

ht

environm

ent in

op

era

tion

2.

bo

un

d(c

on

necte

d)

Facto

rs o

n t

he r

etu

rn t

o

exp

eri

en

ce

(R

EX

)

"

The insuff

icie

nt o

pera

tion

al re

liab

ility

of

sim

ilar

pro

ducts

alread

y d

eve

lop

ed a

nd p

roduced b

y t

he

com

pan

y (

RE

X in

op

era

tion

)

"

Num

ero

us p

roble

ms g

enera

ted in p

rod

uctio

n o

n

sim

ilar

pro

ducts

of

the p

revio

us g

enera

tion

(R

EX

in

pro

duction)

3.

Facto

rs b

ou

nd

to

th

e u

nc

ert

ain

tie

s

"

The u

se o

f te

chno

logie

s in v

ery

in

no

vative

chara

cte

r or

of

the n

ew

str

ate

gie

s o

f im

pla

nting

of

constitu

ents

"

Use o

f ne

w p

rocesses in p

roductio

n

"

The c

onditio

ns o

f em

plo

yment of

the p

rod

uct n

ot

or

little

trie

d

"

Str

on

g v

aria

ble

ness o

f th

e p

rofile

of

use o

f th

e

pro

duct (e

x:

pro

duce

d "

ge

nera

l pu

blic

")

15

se

pte

mb

er

20

05

pa

ge

23

/31

"

Str

on

g v

aria

ble

ness o

f th

e p

erf

orm

ances o

r of

chara

cte

ristics o

f th

e p

rod

uct in

som

e c

onstr

ain

ts o

f

environm

ent or

of

use

"

Sup

ply

besid

e n

ew

sup

plie

rs

"

The u

se o

f constitu

ents

except specific

ation (

ex:

the c

ase o

f constitu

ents

" c

ivili

ans "

used in t

he m

ilita

ry

or

spatial app

lica

tio

ns)

6

Test dura

tion

(da

ys,

we

eks, m

onth

s..)

"

The d

ura

tion o

f a a

ggra

vate

d tests

cam

paig

n is

very

bri

ef

: of

the o

rder

of

5 d

ays o

n a

vera

ge

7

Sep

ara

te o

r com

bin

ed e

nvir

onm

ents

C

om

bin

ed e

nvironm

ents

are

not

a c

on

ditio

n b

ut can b

e

em

plo

yed

if

necessary

to d

isclo

se a

failu

re.

For

exam

ple

, w

e c

an g

rad

ually

incre

ase t

he v

ibra

tion

level fo

r a g

ive

n r

ate

of

tem

pera

ture

variatio

n o

r b

y

incre

asin

g g

radu

ally

this

rate

for

a g

ive

n level of

vib

ration.

8

Pro

duct str

ength

an

d e

nvironm

ent str

ess v

aria

bili

ties

are

or

are

n’t c

onsid

ere

d

( in

th

e p

rocess o

f deri

vin

g t

he t

est severity

)

no

9

Does th

e test

brin

g k

now

ledge o

n r

elia

bili

ty p

ara

mete

rs

?

no

10

Does th

e test co

nsum

e tota

lly o

r p

art

ially

the life

pote

ntial ot th

e e

quip

ment subm

itte

d to t

est ?

Yes , t

he p

roduct

und

er

test is

norm

ally

destr

oye

d

11

main

norm

s , s

tandard

s, te

chnic

al re

fere

nces r

ela

tive t

o

this

type

of

tests

no

15

se

pte

mb

er

20

05

pa

ge

24

/31

D

e v e l o p m e n t T e s t

1

Test obje

ctive

(purp

ose,d

efinitio

n…

)

The p

urp

ose o

f accele

ratio

n is to

pro

duce f

ailu

res in a

reasona

ble

tim

e c

om

pare

d to testing a

t n

orm

al conditio

ns.

Form

s o

f accele

rate

d testin

g inclu

de:

−

accele

rate

d s

tress testing,

AS

T, and

−

accele

rate

d life testing,

AL

T

These a

re m

ade to a

sam

ple

of

pro

ducts

to

id

entify

desig

n w

eaknesses a

s the s

cre

en

ing t

ests

are

made to a

ll pro

ducts

in o

rder

to

prim

arily

ide

ntify

weaknesses in m

ate

ria

ls a

nd

pro

cesses.

Anoth

er

typ

e o

f cla

ssific

atio

n o

f accele

rate

d s

tress tests

can b

e m

ade o

n th

e f

ollo

win

g w

ay:

−

tests

that sim

ula

te th

e u

se c

onditio

ns (

"sim

ula

tion t

esting")

– life tests

−

tests

that

aim

at pro

ducin

g f

ailu

res a

nd locating w

eaknesses (

"stim

ula

tio

n testing

") -

accele

rate

d s

tress tests

Accele

rate

d s

tress testing c

an b

e d

efin

ed a

s a

pply

ing h

igh

er

leve

ls o

f str

ess f

or

a s

hort

peri

od

of

tim

e to a

pro

duct un

der

test

assum

ing

it w

ill e

xh

ibit th

e s

am

e f

ailu

re m

echanis

m a

s it w

ould

in

a long

er

am

ount of

tim

e a

t lo

w s

tress le

vels

. T

esting is d

on

e u

ntil fa

ilure

s take

pla

ce a

nd

the

ke

y is

to u

nd

ers

tand t

he f

ailu

res a

nd t

he

ir r

ela

tio

nship

to t

he a

pplie

d s

tresses. T

he s

tress c

onditio

ns a

re n

ot

meant to

accura

tely

rep

lica

te t

he s

tre

ss life c

ycle

in t

he o

pera

tin

g e

nviro

nm

ent but th

e s

tresses a

re a

nyw

ay s

ele

cte

d to

be e

ffective

in

fin

din

g t

he

failu

res in th

e u

se e

nviro

nm

ent.

Accele

rate

d life testing

is p

erf

orm

ed to o

bta

in info

rmation o

n th

e p

roduct (c

om

ponent, m

odule

, syste

m e

tc.)

lifetim

e d

istr

ibution o

r a

part

icu

lar

relia

bili

ty p

ara

mete

r in

a tim

ely

manner.

This

can b

e d

on

e in t

wo d

iffe

rent w

ays

or

in a

com

bin

ation

of

them

:

- usin

g t

ime c

om

pre

ssio

n, fo

r exam

ple

by c

han

gin

g th

e length

of

on a

nd o

ff c

ycle

s

- accele

rating

the

lo

ad

ing c

onditio

ns, th

us d

ecre

asin

g t

he s

afe

ty m

arg

in

The p

urp

ose o

f lif

e testing is to id

entify

th

e r

ele

vant fa

ilure

mechanis

ms that

wo

uld

occur,

and c

orr

ela

te th

ese w

ith t

he p

oin

t in

the

pro

duct’s life t

he f

ailu

re w

ould

occur.

All

the s

tresses d

uring t

he p

rod

uct’s w

hole

life c

ycle

ne

ed t

o b

e a

ddre

ssed –

e.g

. tr

ansport

ation,

sto

rage a

nd t

he a

ctu

al use c

onditio

ns. T

hese c

ond

itio

ns u

sually

inclu

de

diffe

rent and c

ha

ngin

g t

em

pera

ture

s,

hum

idity,

mechanic

al

str

esses (

vib

rations, sh

ock, bum

ps e

tc.)

, ele

ctr

ica

l a

nd e

lectr

om

agnetic p

henom

ena e

tc.

2

What is

drivin

g y

ou

for

perf

orm

ing the

test?

- safe

ty a

nd r

elia

bili

ty c

oncern

s (

avio

nic

s, nucle

ar

etc

.)

-

main

tenance a

nd

gu

ara

nte

e issues

3

Level of

assem

bly

of

the p

roduct

subm

itte

d to t

est

Quite o

ften th

e g

reate

st

be

nefit of

accele

rate

d t

ests

is a

chie

ve

d b

y p

erf

orm

ing tests

at th

e lo

west

level. T

est should

als

o m

e m

ade e

arl

y

in t

he p

roduct

de

velo

pm

ent pro

cess. H

ow

ever,

testing s

hould

be

continu

ed d

uri

ng

the d

iffe

rent phases o

f th

e p

roduct d

evelo

pm

ent –

from

desig

n p

hase (

testing d

one

on e

arl

y p

roto

typ

es)

to m

anufa

ctu

ring q

ualif

icatio

n a

nd p

eri

od

ic q

ualif

ication t

ests

.

4

Num

ber

of

item

s

subm

itte

d to t

est

For

sta

tistica

l confid

ence t

he n

eed is o

ften h

igh

er

than w

hat

is p

ractica

lly p

ossib

le,

abo

ut five b

ein

g a

min

imum

but fe

w tens w

ou

ld b

e

need

ed.

AT

TA

CH

ME

NT

4 a

cce

lera

ted

te

sts

; p

rop

osa

l :

He

lge

Pa

lmen

15

se

pte

mb

er

20

05

pa

ge

25

/31

5

Typ

e o

f pro

duct

rele

vant

to b

e

subm

itte

d to t

he t

est

( m

ass v

olu

me lo

w

price p

roduct ,..)

All

types.

6

Test dura

tion

(da

ys,

weeks, m

onth

s..)

Accele

rate

d s

tress test ca

n b

e m

ade v

aria

bly

in d

ays o

r fe

w w

eeks. Life testing

typic

ally

req

uires s

evera

l w

eeks, even s

om

e m

onth

s.

7

Sep

ara

te o

r

com

bin

ed

environm

ents

Diffe

rent ty

pes o

f str

esses a

re n

eede

d to

pre

cip

itate

th

e d

iffe

rent fa

ilure

mechanis

ms. P

roper

com

bin

ation o

f str

esses m

ay

be u

se

d to

realis

e s

yn

erg

istic e

ffects

– f

or

exam

ple

th

erm

al cyc

ling a

nd v

ibra

tio

n. H

um

idity is a

lso u

sually

ap

plie

d w

ith h

igher

or

vary

ing

tem

pera

ture

.

8

Pro

duct str

ength

an

d

environm

ent str

ess

vari

ab

ilities a

re o

r

are

n’t c

onsid

ere

d

( in

th

e p

rocess o

f

deri

vin

g t

he t

est

severity

)

Yes.

9

Does th

e test

brin

g

know

ledge

on

relia

bili

ty p

ara

mete

rs

?

Life testing a

ims a

t gett

ing a

n e

stim

ate

of

for

exam

ple

of

the f

ailu

re r

ate

(or

MT

TF

, M

TB

F)

or

the o

n-s

et of

we

ar-

out m

echanis

ms (

life

tim

e)

or

at le

ast

the r

ele

va

nt fa

ilure

mechanis

ms.

10

Does th

e test

consum

e tota

lly o

r

part

ially

the life

pote

ntial of

the

equ

ipm

ent subm

itte

d

to test ?

Accele

rate

d s

tress tests

an

d life tests

are

destr

uctive.

11

main

norm

s ,

sta

ndard

s, te

chn

ical

refe

rences r

ela

tive to

this

type

of

tests

- E

nviro

nm

enta

l te

sting

, accele

rate

d s

tress tests

: IE

C 6

0068-2

– s

tandard

series

- M

echan

ica

l an

d c

limatic test m

eth

ods (

sem

iconducto

r devic

es):

IE

C 6

0749

sta

nd

ard

series

15

se

pte

mb

er

20

05

pa

ge

26

/31

1)

Test

ob

jecti

ve

Develo

pm

ent

tests

are

used to

dete

rmin

e th

e ap

titu

de of

com

ponents

, m

ate

rials

and/o

r desig

ns to

m

et

the re

quirem

ents

(f

unctional

an

d en

viro

nm

enta

l) of

a giv

en

specific

atio

n f

or

a n

ew

pro

duct.

2)

Ap

pli

cati

on

The tests

are

do

ne d

urin

g t

he d

evelo

pm

ent and d

esig

n p

hase o

f a p

roje

ct

with

tw

o a

ims:

-

to d

ete

rmin

e the a

bili

ty o

f m

ate

rials

, com

ponents

an

d/o

r desig

ns to r

esis

t on

eff

ects

of

specifie

d e

nviro

nm

enta

l co

nditio

ns,

were

experi

ence is m

issin

g a

nd/o

r ca

lcula

tio

n

or

virtu

al sim

ula

tion is n

ot

possib

le o

r n

ot e

nou

gh a

ccu

rate

. -

to d

ete

rmin

e the a

bili

ty o

f a

desig

n s

olu

tion t

o m

et th

e f

unctio

na

l re

quirem

ents

of

a g

iven

specific

ation.

While

bein

g a

n s

ubsta

ntia

l part

of

develo

pm

ent

costs

and a

n im

port

ant

desig

n t

ool,

it is n

ecessary

to p

lan a

nd t

o b

udg

et

the D

ev

elo

pm

en

t T

ests

at

the v

ery

beg

inn

ing o

f a

develo

pm

ent pro

ject. T

he p

rincip

al in

put fo

r th

is p

lanin

g a

ctivity is th

e p

roduct spe

cific

ation

3)

Kin

d o

f T

est

Regard

ing t

he r

eq

uire

d e

nvironm

enta

l co

nd

itio

ns,

all

kin

ds o

f exis

ting e

nvironm

enta

l T

ests

ma

y b

e u

sed,

but

norm

ally

with

much h

igher

str

ess lim

its t

han t

hose g

iven b

y t

he

specific

atio

n.

The r

ais

on f

or

usin

g h

igh s

tress lim

its is t

o s

pare

test

tim

e a

nd t

o g

et

som

e f

acto

r of

security

re

gard

ing t

he t

est

results.

(HA

ST

: H

ighly

Accele

rate

d S

tress T

est;

HA

LT

: H

ighly

Accele

rate

d L

ifecyc

le T

est)

Outg

oin

g f

rom

the s

pecifie

d e

nviro

nm

enta

l re

qu

irem

ents

rela

ting t

o o

pera

tion,

transport

atio

n a

nd s

tora

ge

, th

e a

ppro

pri

ate

test

pro

ced

ure

s,

the s

tress l

evels

and

the t

est

dura

tion s

hall

be c

hosen

, consid

erin

g th

e e

xperi

ences w

ith e

arl

ier

develo

pm

ent an

d the

know

-ho

w o

f th

e test

specia

lists

.

15

se

pte

mb

er

20

05

pa

ge

27

/31

4)

Test

Co

nd

itio

ns

To a

llow

to d

ete

rmin

e t

he e

ffect

of

sin

gle

str

ess f

acto

rs o

n a

mate

rial or

item

respectively

to a

vo

id t

he r

ecip

rocal in

flu

ence o

f severa

l str

esses,

the t

est

conditio

ns a

re u

sually

specia

l la

b c

on

ditio

ns, not

equa

l to

th

e r

ea

l e

nvironm

enta

l cond

itio

ns o

f th

e p

rod

uct.

Rem

ark

: C

om

bin

ed t

ests

(H

um

idity/T

em

pera

ture

; V

ibra

tion

/Tem

pera

ture

etc

.) a

re a

lso o

ften u

sed,

but

norm

ally

app

lied o

n t

he f

inal

pro

duct

and n

ot

for

the p

urp

ose s

tate

d

out u

nder

1).

5)

Test

Resu

lts

The t

est

results a

re u

sed t

o m

ake d

esig

n d

ecis

ions a

s w

ell

as t

o e

va

luate

the "

Re

liab

ility

" a

nd/o

r th

e "

Life T

ime"

of

a p

rod

uct

an

d t

o p

rove t

he r

ightn

ess o

f a d

esig

n.

There

for

the t

est re

sults, m

eth

ods, to

ols

and c

onditio

ns s

ha

ll b

e d

ocum

ente

d a

nd

sto

red o

n s

uch a

wa

y,

that th

e p

rob

abili

ty o

f lo

osin

g o

r dis

tracting th

en is v

ery

lo

w.

15

se

pte

mb

er

20

05

pa

ge

28

/31

Ac

ce

lera

ted

te

sts

pro

po

sa

l b

y H

en

ri G

rze

sko

wia

k

prin

cip

e

Co

nd

itio

ns o

f a

pp

lica

tio

n

Exp

ecte

d r

esu

lts

Ob

jective

: re

du

ce

th

e te

st

du

ratio

n

Prin

cip

le:

the

p

rod

uct

is su

bje

cte

d to

co

nd

itio

ns

of

use o

r to

co

nstr

ain

ts o

f

en

viro

nm

ent

am

plif

ied

in

o

rde

r to

acce

lera

te

the

m

ech

an

ism

s

of

faili

ng

an

d t

o r

ed

uce

th

e n

ece

ssa

ry d

ura

tion

to

estim

ate

som

e

beh

avio

ral

ch

ara

cte

ristics

of

the

pro

du

ct

in

the

no

rma

l co

nd

itio

ns o

f em

plo

ym

en

t

Kn

ow

th

e

an

aly

tica

l m

ode

l m

akin

g

the

re

latio

n b

etw

ee

n th

e sp

ee

d of

da

ma

ge

w

ith

th

e

am

plit

ud

e

of

the

ap

plie

d c

ond

itio

ns

Kn

ow

th

e

va

lue

of

the

pa

ram

ete

rs

invo

lve

in

th

ese

mo

de

ls

The

pro

vo

ke

d m

ech

anis

ms o

f fa

ilure

ha

ve

to

b

e

rep

rese

nta

tive

of

tho

se

arisin

g in

th

e no

rma

l co

nd

itio

ns of

em

plo

ym

en

t

The

p

hen

om

en

a

of

inte

ractio

ns

be

twe

en

se

ve

ral

co

nstr

ain

ts

of

em

plo

ym

en

t o

r of

en

viro

nm

en

t m

ust

be

ta

ke

n in

to a

ccou

nt.

Eva

lua

tio

n

of

the

be

ha

vio

ral

ch

ara

cte

ristics of

a pro

du

ct

in

the

no

rma

l co

nd

itio

ns

of

em

plo

ym

en

t,

it

for

the

co

mpa

tib

le

pe

rio

ds

with

th

e

ca

len

da

r co

nstr

ain

ts a

sso

cia

ted

to t

he

ph

ase

of

de

ve

lop

men

t of

the

pro

du

ct

15

se

pte

mb

er

20

05

pa

ge

29

/31

__

___

__

__

___

__

__

__

__

___

__

__

__

__

___

__

__

__

__

G

UID

E

En

vir

on

men

tal

Str

ess S

cre

en

ing

fo

r E

lectr

on

ic E

qu

ipm

en

t

usin

g H

igh

ly A

cc

ele

rate

d T

ests

__

___

__

__

___

__

__

__

__

___

__

__

__

__

___

__

__

__

__

January

20

06 E

ditio

n

Mem

bers

of

the A

ST

E E

nvir

onm

enta

l S

tress S

cre

en

ing C

om

mitte

e

havin

g p

art

icip

ate

d in th

e im

ple

menta

tio

n o

f th

is D

ocu

ment

Com

mitte

e P

resid

ent :

Danie

l G

OU

LE

T

T

hale

s D

ivis

ion A

éro

sp

ace

C

om

mitte

e m

em

bers

:

Serg

e B

LA

ZE

JE

WS

KI

Johnson C

ontr

ol

Vin

ce

nt D

ER

OU

ET

F

lextr

on

ics

Fra

ncis

DU

PO

UY

Serm

a T

echnolo

gie

s

Joëlle

DU

SS

AU

LT

A

irb

us

Cla

ude G

IGO

UX

Im

dR

-SD

F

Fabrice G

UE

RIN

IS

TIA

P

hili

pp

e J

EA

NP

IER

RE

E

mitech

Phili

pp

e P

OU

GN

ET

V

alé

o V

EM

S

Jacques R

ING

LE

R

Rin

gle

r C

onsu

ltin

g

Jean M

arie R

OU

RE

V

alé

o V

EC

S / C

EE

Lio

nel S

IMO

N

S

ole

ctr

on

Fré

déric T

RE

NIT

EC

ET

15

se

pte

mb

er

20

05

pa

ge

30

/31

Co

nte

nts

1..

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

In

tro

du

cti

on

an

d h

isto

rical b

ackg

rou

nd

5

2..

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

...

Ob

ject

6

3..

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

. D

om

ain

of

ap

plicati

on

6

4..

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

. T

erm

ino

log

y

6

5..

....

.. R

em

ind

er

of

the e

nvir

on

men

tal

str

ess s

cre

en

ing

ob

jecti

ves a

nd

pri

ncip

les

7

6..

....

....

....

....

....

....

....

....

....

....

....

. T

he E

SS

op

era

tio

ns a

t vari

ou

s s

tep

s o

f *a

ssem

bly

*

9

6.1

The n

otions o

f hom

og

eneous / h

ete

rog

eneous p

roducts

in fro

nt of

resis

tance t

o c

onstr

ain

ts

9

6.2

....

....

....

....

....

....

....

....

....

....

....

....

...

Incid

ence o

n the testing m

eans s

pecific

ation:

11

7..

....

....

. Ju

sti

ficati

on

of

the “

Hig

hly

accele

rate

d e

nvir

on

men

tal

str

ess s

cre

en

ing

” 1

3

7.1

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

... C

om

parison o

f th

e tw

o m

eth

ods

13

7.1

.1..

....

....

....

....

....

....

.. “

Conventional environm

enta

l str

ess s

cre

enin

g”

meth

od

14

7.1

.2..

....

....

....

....

. “H

ighly

accele

rate

d e

nvironm

enta

l str

ess s

cre

enin

g”

meth

od

16

7.2

....

....

....

....

....

....

....

...

Com

parison o

f th

e e

nvironm

ent str

ess s

cre

enin

g m

eth

ods

18

7.3

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

. O

ther

advanta

ges

19

7.4

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

. P

ote

ntial pro

ble

ms a

nd p

recautions:

19

8..

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

.. I

nit

ial E

SS

pro

file

set

up

20

8.1

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

...

ES

S p

rofile

phases 2

0

8.2

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

. S

ele

ction o

f th

e a

pplic

able

constr

ain

ts:

21

8.3

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

Choic

e o

f th

e E

SS

constr

ain

ts levels

21

8.3

.1..

....

....

....

....

....

....

....

....

....

....

....

...

Fix

ed t

em

pera

ture

s c

ases (

warm

or

cold

)

22

8.3

.2..

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

. T

herm

al cycle

s c

ases

24

15

se

pte

mb

er

20

05

pa

ge

31

/31

8.3

.3

Pseudo-u

npre

dic

table

vib

rations c

ases (

3 a

xes, 6 d

eg

rees o

f fr

eedom

) ..

...

27

8.3

.4

Therm

al cycle

s c

om

bin

ed w

ith v

ibra

tions 3

axes 6

deg

rees o

f fr

eedom

: ..

...

28

8.4

....

....

....

....

....

....

....

....

....

....

....

....

.. C

onstr

ain

ts h

arm

lessness o

n s

ound p

roducts

2

9

9..

....

....

....

....

....

....

....

....

....

....

....

...

Ch

ara

cte

risti

cs o

f th

e in

terf

aces u

sed

fo

r th

e E

SS

32

10

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

In

itia

l p

rofi

le a

nd

testi

ng

mean

s v

ali

dati

on

3

3

10.1

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

...

Valid

ation o

f th

e E

SS

harm

lessness

34

10.2

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

.. V

alid

ation o

f th

e E

SS

effic

iency

36

11

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

. M

an

ag

em

en

t o

f th

e E

SS

op

era

tio

n

39

11.1

....

....

....

....

....

....

....

.. R

ealis

ation a

nd m

onitoring o

f th

e t

ests

, fa

ilure

s d

ete

ction

39

11.2

....

....

....

....

....

....

....

....

....

....

....

....

....

....

Applic

able

pro

cedure

s in c

ase o

f fa

ilure

s

40

11.3

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

. C

apitalis

ation o

f th

e r

esults

40

11.4

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

. T

he E

SS

optim

isation

42

12

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

Cli

en

t /

su

pp

lier

inte

rface

12.1

....

....

....

....

....

....

....

....

....

....

....

....

....

. R

esponsib

ilities a

nd c

ontr

actu

al m

odalit

ies

43

12.2

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

. E

SS

pro

file

valid

ation t

ests

synth

esis

4

4

13

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

....

.. B

iblio

gra

ph

ical re

fere

nces

45

Ap

pen

dix

es

Appendix

A:

E

SS

by s

am

plin

g

Appendix

B:

S

om

e o

rders

of m

ag

nitude