Bsi bs cecc 00016 1991 (1999)

BRITISH STANDARD BS CECC 00016 1991 Harmonized system of quality assessment for electronic components Basic specification Basic requirements for the use of statistical process control (SPC) in the CEC[.]

00016:1991

This Bri sh Stan ard, ha ing

b en pre ared u der the

directonof the Electronic

Comp nents Stan ards

PolicyCommi e , was

publishedu der the authoriy

ofthe Stan ards Bo rd an

comesinto efect on

2 Decemb r1 9

© BSI 0 -1 9

The folowing BSI references

relate to the work on this

stan ard:

Commi e reference E L

Draft for comment 8 / 25 1 DC

ISBN 0 5 0 2 3 7 3

This British Stand ard was entrusted b the Electronic Components Stand ards

Pol cy Commit e ( ECL/ -), upon which the folowing bod ies were represented :

BEAMA Ltd

British Stand rds Society

British Telecommu ications plc

EEA ( The Association of the Electronic , Telecommu ications and Busines

Equipment Ind ustries)

Electronic Components Industry Federation

Ministry of Defence

National S perv ising Inspectorate

Society of British Aerosp ce Comp nies Limited

Am endm ents is ued sinc publ cation

Pag e

National foreword

This British Stand ard has be n prep red u der the d irection of the Electronic

Components Stand rds Pol cy Commit e It is id entical with CECC0 016:19 0

“ Ha r monized system o qua liy a ss s ment fr ele tr onic components: B a sic

spe ifica tion: B a sic r equir ements f r the us o sta tistca l pr oc s contr ol (SPC) n

the CECC System”, publshed b the European Commit e for Electrotechnical

Stand rd ization ( CENELEC) Electronic Components Commit e ( CECC)

This stand ard d efines the req uirements for the a pl cation of statistical proces

control ( SPC) in the CECC Sy stem in order to improv e the q ual ty of proces es,

prod ucts an serv ices b contin al y reducing proces v ariation

The British Stand ard which implements the CECC Rules of Procedure is BS9 0

“ Gener a l r equir ements f r a system fr ele tr onic components o a ss s ed

qua liy” — Part 2:19 1 “ Spe ifica tion fr the na tiona l implementa tion o the

CECC System”

The Electronic Components Stand rds Polcy Commit e has rev iewed the

prov isions of CECC0 01 to which reference is ma e in the tex t and has decid ed

that they are ac epta le for use in conju ction with this stand ard

A British Stand ard d oes not purport to includ e al the neces ary prov isions of a

contract User of British Stand rd s are responsible for their cor ect a plcation

Com pl anc with a British Standard does not ofitself confer im m unity

f om leg al o l g ations

Cros - referenc s

Inte national s and rd Cor esp nding British Stand rd

CECC 0 1 4:RP 14 BS CECC 0 1 4: Qua liy a ss s ment pr oc d ur es

Part I Part 2:19 1 Qua lifica tion a ppr ova l o ele tr onic

components

( Identical

CECC 0 1 4:RP 14 BS CECC 0 1 4: Qua liy a ss s ment pr oc d ur es

Part I I Part 3:19 1 Ca pa biiy a ppr ova l o a n ele tr onic

component ma nufa ctur ing a ctviy

( Identical

EN 29 01 BS 5 5 : Qua li y systems

Part 1:19 7 Spe ifica tion f r d esign/d evelopment,

pr od ucton, insta lla tion a nd s r vicing

( Identical

Sum mary of pag es

This document comprises a f ont cov er, an insid e font cov er, p g es i an i ,

theCECC title p g e, p g es i to iv , p g es1to6, an insid e b ck cov er and

ab ckcov er

This stand rd has be n up ated ( se copy rig ht d ate) an ma hav e ha

amendments incorporated This wi l be ind icated in the amendment ta le on

theinside f ont cov er

Pag e

4 Relationship of SPC with CECC Qual fication Approv al

The CENELEC Electronic Components Commit e ( CECC) is composed of those

member countries of the European Commit e for Electrotech ical

Stand ardization ( CENELEC) who wish to take p rt in a harmoniz d Sy stem for

electronic components of as es ed q ual ty

The object of the Sy stem is to faci itate international tra e b the harmonization

of the specifications and qual ty as es ment procedures for electronic

components, and b the g rant of an internationaly recog niz d Mark, or

Certificate, of Conformity The components produced u der the Sy stem are

thereb ac epta le in al member cou tries without further testing

At the d te of printing of this specification, the member cou tries of the CECC

are Austria, Belg ium, Denmark, Finland , France, Germany , I eland, Italy , the

Netherland s, Norway , Portug al, Sp in, Sweden, Switz rlan an the United

King dom, an copies of it can be obtained fom the ad dres es shown on the blue

fly she t

Pr face

This Basic Specification was prep red b the CECC Task For e on Statistical

Proces Control

The text of this specification was cir ulated to the CECC for v oting in the

d ocument indicated below and was ratified b the President of the CECC for

printing as a CECC Specification

CECC( Sec etariat)24 0 February 19 0 CECC( Sec etariat)2628

1 Introduction

CECC a prov ed components are released u d er

either Qualfication Approv al

( se CECC 0 1 4:RP14 Part I ), or Ca a i ity

Approv al ( se CECC0 1 4:RP14 Part I I)

Statistical Proces Control ( SPC) is a to l which

ma be used within the CECC Sy stem to

d emonstrate the deg re to which the relev ant

man facturing proces es are u der control

W hen the tech ique is properly a pl ed, it can as ist

in improv ing the outg oing product q ualty ,

p rticularly where the n mber of non-conforming

items ma be ex res ed as a low n mber of p rts per

mi lon ( ppm) No conv entional sampl ng plan, nor

even 10 % inspection, can ac urately sep rate out

these low lev el non-conforming items

The only v ia le a proach to q ualty in this situation

is to institute a prev entiv e method olog y in the

man facturing proces to buid q ualty into the

product, a opting a “ proactiv e” method which

al ows for the improv ement of the proces on a

contin ing b sis SPC is used at the operational

lev el to red uce proces v ariation

SPC is b sed upon the prev ention of fai ures

throug h the a plcation of statistical to ls It do s

not el minate the measurement of prod ucts or of

product p rameter , i.e inspections, which ma be

car ied out on a samplng b sis or 10 % Howev er,

statistical analy sis wi prov id e insig ht into the

proces an op ortu ities for improv ement As the

proces improv es, there is a reduced ne d for

extensiv e testing after the product is completed,

with a conseq uent lowering of the man facturing

cost

By the use of statistical tech iq ues, proces

v ariation with time can be q uantified Cor ectiv e

actions which are b sed on this information wi

lead to contin ing improv ement in proces es and

prod ucts

A prereq uisite for efectiv e implementation of an

SPC sy stem is manag ement commitment This

commitment is d emonstrated b inv olv ement an

p rticip tion in project selection, prog res rev iews

and contin ing improv ement activ ities

2 Scope

This specification defines the requirements for the

a pl cation ofstatistical proces control ( SPC) in the

CECC Sy stem in order to improv e the qual ty of

proces es, products and serv ices b contin al y

reducing proces v ariation

3 Terminolog y

3.1

comm on or random cause

a sour e of natural v ariation that afects al

ind iv idual v alues of the proces output being

studied

3.2

control lo p

a cor ectiv e sy stem b sed on fe d ack procedure

3.3

control l mits

the ma imum alowa le v ariation of a proces

characteristic due to common causes alone

Variation bey ond a control l mit is ev id ence that

special causes ma be afecting the proces Control

l mits are calculated f om proces d ta

3.4

node

a point in the proces where form, fit or fu ction is

altered

3.5

proc s

a combination of pe ple, machines, equipment,

materials, proced ures, methods and env ironment

that produces a g iv en prod uct or serv ice

3.6

spe ial or as ig na le cause

a sour e of v ariation that is intermit ent or

u predicta le, afecting only some ind iv idual v alues

of the proces output

3.7

targ et v lue

the nominal v alue of a characteristic

3.8

v riation (se Note)

the d iference betwe n ind iv idual outputs of a

proces ; the sour e of v ariation can be g rouped into

two major clas es: common causes an special

causes

NOT “V aria iliy” is sometmes used as an alternatv term

3.9

statistical control

the condition d es ribing the proces f om which al

special causes hav e be n remov ed and only common

causes remain; this is d emonstrated b the a sence

of points bey on the control lmits and b the

a sence of non-random p t erns or trends within

the control l mits

3.10

statistical proc s control (SPC)

the conv er ion of d ata to information using

statistical techniques to document, cor ect, an

improv e proces per ormance

3.1

fai ure m ode and efe t analysis (FMEA)

a dis ipl ned analy sis of pos ible faiure mod es on

the b sis of seriousnes , prob bi ity of oc urence

an lkel ho d of detection.FMEA ma be a pled to

both the d esig n and the man facturing proces

3.12

fault tre analysis (FTA)

( und er consid er a tion)

3.13

proc s potential

an as es ment of proces ca a i ty mad e fom a

relativ ely smal amou t of sample d ta g athered

ov er a short period of time, normal y car ied out in

a period of piot or pre-production

3.14

proc s ca a i ity

the natural v ariation of the proces d ue to common

causes

3.15

proc s characteristic

a d isting uishing feature of a proces or its results on

which v aria les or at ributes d ta can be colected

3.16

proc s potential index (C

p ) and proc s

ca a i ity index (C

pk )

measures of the relationship betwe n the

specification l mits an the proces ca a i ity

3.17

control chart

a plot of a proces characteristic ( for instance

d isplay ed as mean, rang e, stand rd dev iation,

per entag e of d efects) in its natural order ( i.e time

of man facturing )

4 Rela tionship ofSPC with CECC

Qual fication Approva l and Ca pabi ity

The CECC Sy stem is b sed on the as es ment of

q ual ty in ac ord ance with comprehensiv e,

consistent an precise specifications The initial

as es ment is car ied out b means of q ualfication

or ca a i ty a prov al testing , and is fol owed b

testing on a lot-by -lot an periodic b sis

SPC tech iques and concepts ma be used b the

man facturer as a means of achiev ing a consistent

lev el of q ualty in as ociation with the requirements

of the CECC Sy stem

For ca a i ity a prov al SPC information ma be

used in sup ort of the demonstration of ca a i ty

within the defined tech olog y and for release of

prod uct S ch information ma be ex res ed

q uantitativ ely , for instance as ca a i ity indices

For qualfication a prov al it is neces ary to d efine

and d emonstrate a satis actory cor elation betwe n

proces d ta and product characteristic before SPC

information can be used as p rt of conformance

inspection

5 Genera l r quir ments

5.1 The man facturer shal define an SPC system

inv olv ing c itical or key proces nodes

5.2 The man facturer shal comply with the

fol owing SPC — relev ant requirements of

EN29 01 “ Qua liy systems — Mod el f r qua liy

a ssur a nc in d esign/d evelopment, pr od ucton,

insta lla tion a nd s r vicing”:

CECC 0 01 : Cal bration requirements for the

CECC Sy stem

These req uirements form the infastructure for the

prep ration an implementation of SPC

6 Specific r quirements

6.1 Preparing for SPC

6.1.1 Q ual ty plans ( clause4.4.2 of EN29 01)

The man facturer shal prep re writ en qualty

plans for projects relating to new proces es These

plans shal includ e the activ ities concerning the

definition and testing of the proces and its controls

Clause: Requirem ent:

4.1 Manag ement responsibi ty

4.2 Qual ty sy stem

4.8 Product id entification an tracea i ity

4.10 Inspection an testing

4.12 Inspection and test status

4.13 Control of nonconforming prod uct

4.14 Cor ectiv e action

4.16 Qual ty record s

4.17 Internal q ual ty audits

4.2 Statistical tech iques

6.1.2 Node and charact eristic ( clause4.9 of

EN290 1)

The manufacturer shal d etermine a propriate

characteristic to be measured for the c itical or key

nodes To ls to be used whie esta lshing those

characteristic ma include Faiure Mod e and Efect

Analy sis ( FMEA), fault tre analy sis ( FTA), cause

and efect diag rams and proces flow charts

6.1.3 Target value and l mits ( clause4.9 of

EN290 1)

The targ et v alues and the lmits of the

characteristic bey ond which the proces wi

produce u ac epta le ( semi finished products

shal be esta lshed These l mits are cal ed

specification lmits

6.1.4 St eering means ( clause4.9 of EN290 1)

The manufacturer shal define the ste ring means

neces ary to ke p the proces u d er control

6.1.5 Wo k inst ructions ( clause4.9 of EN290 1)

The manufacturer shal prep re documented work

instructions includ ing inspection methods, the

definition of deficiencies an the statistical methods

to be used b the proces operator

6.1.6 De ign reviews ( clauses4.4 and 4.9 of

EN290 1)

The manufacturer shal org aniz desig n rev iews at

defined interv als during the dev elopment of the

proces All aspects of the dev elopment shal be

considered

6.1.7 Pr c s potential st udie ( clause4.9 of

EN290 1)

The manufacturer shal car y out proces potential

studies; test ru s shal be mad e to observ e the

proces characteristic The results shal be

statistical y analy sed , special causes shal be

el minated an u wanted trends shal be cor ected

6.1.8 Pr c s cap bi it y studie ( clause4.9 of

EN290 1)

The manufacturer shal esta lsh the proces

ca a i ity whi e operating it u d er actual

production cond itions unti al factor l kely to

contribute to proces v ariation are reflected in the

proces output During the inv estig ation special

causes shal be identified an el minated to leav e

the proces in statistical control Data resulting

f om special causes can only be el minated if there is

no pos ibi ty of recur ence

From the proces d ata, control lmits shal be

calculated an are to be used b operator as a b sis

for judg ing whether a proces is afected b special

causes

6.1.9 Training (cla us 4.18 o EN2 0 1)

The man facturer shal define, implement and

maintain an SPC training prog ramme for al

per onnel ( includ ing manag ement) inv olv ed with

SPC, reflecting the extent of their contribution

Special at ention shal be p id to statistical aspects

6.1.10 Management co re tive action

(cla us 4 1.2 o EN2 001)

The man facturer shal d efine the manag ement

inv olv ement in the sy stematic improv ement of the

proces ca a i ity on a contin ing b sis

6.2 Proc s control requirem ents ( clause4.9 of

EN29 01)

6.2.1 G eneral

During prod uction, measurements and observ ations

shal be car ied out ac ording to the writ en

instructions.I a characteristic is outside its control

l mit( s), or if u wanted trend s are detected , the

proces shal be cor ected with the aid of defined

ste ring means

Action shal be taken to prev ent shipment of

nonconforming prod ucts if specification l mits are

exce d ed

6.2.2 Pr c s relat ed purchas d materials and

s r ic s ( clause4.6 of EN290 1)

The man facturer shal ensure that his sup l er of

materials an serv ices hav e or instal a prog ramme

for the contin ing red uction of v ariation of proces

related materials and serv ices defined as c itical

6.2.3 Pr c s cap bi it y ( clauses4.9 and 4.16 of

EN290 1)

The man facturer shal be a le to d emonstrate the

proces ca a i ity This ma be done b means of:

— control charts

— proces ca a i ty indices ( C

p , C

pk )

6.2.4 Analys s ( clauses 4.16 and 4.2 of EN290 1)

The man facturer shal g ather proces d ata, causes

for non-rand om p t erns and results of cor ectiv e

actions as a b sis for contin ing improv ement

Analy ses shal be ma e at defined inter v als and

sup orted b statistical techniq ues

6.2.5 Impr vement (s) o change s)

The man facturer shal prep re and introduce

improv ement( s) or chang e( s) ac ording to the

req uirements of 6.1 The extent to which the

req uirements of 6.1 a ply shal be related to the

consequences of the improv ement( s) or chang e( s)

As a minimum a proces potential stud and a

proces ca a i ity stud y shal be car ied out

Control lmits shal be recalculated ac ording ly