Tiêu Chuẩn Iso 22262-3-2016.Pdf

© ISO 2016 Air quality — Bulk materials — Part 3 Quantitative determination of asbestos by X ray diffraction method Qualité de l’air — Matériaux solides — Partie 3 Dosage quantitatif de l’amiante par[.]

A ir quality — Bulk materials —

Part 3:

Qu lité de l’air — Matériau solides —

Partie 3: Dosage q a titatifde l’amiante p r la méth de de

diffraction des ra o s X

Fir t edition

2 16-1 -0

Refer ence n mb r

ISO 2 262-3:2 16(E)

COPYRIGHT PROTECTED DOCUMENT

© ISO 2016, P blshed in Sw itz rlan

A ll rig hts r eserved Unles otherw ise spe ified, nopar of this p blc tion ma y be r epr od c d or utilz d otherw ise in an form

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written permis ion Permis ion c n be req esed from either ISO at the ad r es below or ISO’s member bod y in the c u try of

F reword v

Introduction vi

1 Sc ope 1

2 Nor mati ve r eferenc es 1

3 Terms an definitions 1

4 Rang e 3

5 Limit of q antification 3

6 Symbols and abbreviated terms 4

7 Requirements for quantification 4

8 A pparatus and reag ents 5

8.1 A pp r atus 5

8.2 Reag ent 6

9 Quantitati ve X RD metho and principle 7

9.1 Q uantitative X R D methodsusing an exte nal s an ar d 7

9.2 Summary of the q antitative method 7

9.3 Pr eparation of wor king curve an measur ement 8

9.4 Inte ferenc minerals 9

10 Preparatio of c omminuted sample 9

1 1 Pr eparation of comminuted sample fr om orig inal sample 9

1 2 Heat r eatment of comminuted samples that contain or ganic constituent 9

1 3 Pr etr eatment for pr ep ration of r esid al samples 1

1 4 Pr eparation of sub-residual samples 1

11 Difractio pe ks for anal ysis of asbestos and of inter ferenc e materials 11

1 1 Difraction peaks for q antitative analysis of asbes os 1

1 2 Inte ferenc minerals 1

1 2.1 Pos ible inte fer enc minerals 1

1 2.2 Mas r ed ction tr eatment for dis olving inte fer enc minerals 1

12 Quantitati ve anal ysis b X RD employing substrate standard mas absorptio c or rectio 16 1 1 General

1 1 2 Pr eparation of wor king curve 1

1 2.1 Pr ep ration of wor king curve I 1

1 2.2 Pr ep ration of wor king curve I 1

1 3 Pr oc dure for q antitative analysis 1

1 4 Calculation of asbes os mas fraction 1

1 4.1 C lculation of asbes os mas fraction fr om a r esid al sample 1

1 4.2 C lculation of theasbes os mas fraction fr om a sub-r esid al sample 1

1 5 L we lmit of dete tion an q antitative dete mination for the wor king curve 1

1 6 Ev luation of u c rtainty ofX R D measur ement 2

13 Test rep r t 20

A nne x A (normative) X-ray difractomete parameter for q antitati ve anal ysis of asbestos 22

A nne x B (normative) Substrate standar d mas absor ption c orrectio for

asbestos quantificatio 26

A nne x C (informative) T ypes of c ommercial asbestos-c ontaining mater ials and optimum

anal ytical proc edures 27

A nne x D (informative) Efects of matr ix r eductio methods 38

A nne x E (informative) Rang e of typical detection lmits and evaluation of uncertainty of

quantitati ve X RD me surements b X RD metho 41

Biblog raph y 45

ISO (he Int ernational Org nization for Stan ardization) is a worldwide fede ation of national s an ards

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through ISO t ech ical committ ees Each membe b dy int er st ed in a subje t for w hich a t ech ical

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ISO cola orat es closely with the Int ernational Ele trot ech ical C mmis ion (IEC) on al matt ers of

ele trot ech ical s an ardization

The proc d r s used t o develo this document an those int en ed for it furthe maint enanc ar

desc ibed in the ISO/IEC Dir ctives, Part 1 In p rticular the dife ent a pro al c it eria ne ded for the

dife ent ty es of ISO document should be not ed This document was draft ed in ac ordanc with the

edit orial rules of the ISO/IEC Dir ctives, Part 2 ( e www.iso.org dir ctives)

A tt ention is drawn t o the p s ibi ity that some of the element of this document ma be the subje t of

p t ent right ISO shal not be held r sponsible for identifying any or al such p t ent right Detais of

any p t ent right identif ied d ring the develo ment of the document wi be in the Introd ction an / r

on the ISO ls of p t ent de larations r c ived ( e www.iso.org p t ent )

Any trade name used in this document is information given for the convenienc of use s an does not

cons itut e an en orsement

F or an ex lanation on the meaning of ISO spe if ic t erms an ex r s ions r lat ed t o conformity

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Bar ie s t o Trade (TBT) se the fol owing URL: F or word - Sup lementary information

The committ ee r sp nsible for this document is ISO/TC 146, Air q alt y, Subcommitt ee SC 3, Ambient

atmos phe es

ISO 2 2 2 consis s of the folowing p rt , u de the g ene al title Air q alt y — B ulk mate ial s:

— Part 1: S mpln a d q altati ve dete min tio o asbes tos in c omme c ial b lk mate ial s

— Part 2 : Qu ntitative dete min tio o asbes tos b grav imetric a d mic rosc opic al meth ds

— Part 3: Qu ntitati ve dete min tion o asbes tos b X-ra difrac tio meth d

In the p s , asbest os was used in a wide rang e of prod ct Mat erials containing high pro ortions

of asbest os we e used in buidings and in in us ry for f ir pro fing, the mal insulation an acous ic

insulation Asbest os was also used t o r infor e mat erials an t o impro e fractur an ben ing

charact eris ics A larg e pro ortion of the asbest os prod c d was used in asbest os-c ment prod ct

These inclu e flat he t , ties and cor ug t ed she t for ro f ing, pipes an o en troughs for cole tion

of rainwat er an pr s ur pipes for sup ly of p ta le wat er Asbest os was also incorp rat ed int o

prod ct such as de orative co tings an plast ers, glues, sealant and r sins, flo r ti es, g sket an

ro d pa ing In some prod ct , asbest os was incorporat ed t o modify rheolo ical pro e ties, for ex mple

in the man factur of c i ing tie p nels an oi dri lng mu s

Whi e the asbest os conc ntration in some prod ct can be ve y high an in some cases a pro ches

1 0 %, in othe prod ct the conc ntrations of asbest os used we e signif icantly lowe an oft en

betwe n 1% an 1 % In some c i ing tie p nels, the conc ntration of asbest os used was close t o 1 %

The e ar only a few k own mat erials in w hich the asbest os conc ntration used was les than 1 %

Some ad esives, seal ng comp un s an f ile s we e man factur d in w hich asbest os conc ntrations

we e lower than 1 % The e ar no k own comme cialy man factur d mat erials in w hich any one

of the common asbest os v rieties (chry sotie, amosit e, c ocidolt e or antho hy llt e) was int entionaly

ad ed at conc ntrations lowe than 0,1 %

ISO 2 2 2-1 spe if ies the proc d r s for cole tion of samples an q altative analy sis of asbest os in

comme cial bulk mat erials using mic osco ical methods such as p lariz d lght mic osco y (PLM)

ISO 2 2 2- 2 spe if ies theproc d r s for the det ermination of asbest os mas fractions in bulk mat erials

b mic osco ical methods

This part of ISO 2 2 2 spe if ies the analytical proc d r s for the q antitative det ermination of asbest os

b X-ra p wde difraction (XRD ) The proc d r employ s a subs rat e s an ard mas a sorption

cor e tion method t o q antify asbest os that was pr viously identified b the mic osco ical method

in ISO 2 2 2-1 Whie the XRD method is useful for q altative analy sis of c y stal ne subs anc s in

p wde samples b measur ment of difraction p tt erns that can be r lat ed t o c y stal s ructur , XRD

analysis cannot dis inguish between dife ent morpholo ical ha it of the same mine al Th s, XRD

cannot disc iminat e betwe n the asbes iform an non-asbes iform analo ues of se pentine an the

amphib les Furthe mor , the primary difraction peaks for dife ent amphib les l e within a ve y

nar ow rang e an it is not p s ible t o q antify in ivid al amphib les w hen a mixtur of amphib les is

pr sent Difraction peaks a pearing in XRD p tt erns of the asbest os-forming mine als ar conside ed

t o be “ pos ible peaks of asbest os” , as umed t o r pr sent the asbest os det ect ed d ring analy sis in

ISO 2 2 2-1 Howeve , if non-asbes iform se pentine or non-asbes iform amphib le mine als ar

pr sent in the sample matrix, the “ pos ible peaks of asbest os” wi r pr sent them A ccordingly,

this method is not int en ed for a plcation t o samples in w hich non-asbes iform se pentine or

non-asbes iform amphib le mine als ar pr sent

A conventional XRD method, w hich employ s a p wde sample mou t ed in a p wde spe imen holde

an a scinti lation cou t er, can q antify a c y stal ne mat erial at a conc ntration of a pro imat ely 1 %

The XRD method using a subs rat e s an ard mas a sorption cor e tion method emplo ed in this p rt

of ISO 2 2 2 can det ect the difraction peaks of chry sotie asbest os from q antities as low as 0,0 mg

on a membrane f ilt er of 2 cm

2

ar a [0,0 mg filt er (2 cm

2

)] as shown in R efe enc s [1 ] an [14] The

amou t of sample on the f ilt er is l mit ed t o 1 mg d e t o the l mit of the X-ra a sorption cor e tion In

this method, gra imetric matrix r d ction proc d r s ar used t o r d c the matrix cons ituent an

int erfe enc mine als in a 1 0 mg commin t ed sample When the matrix r d ction achieves a r sid al

ratio of 1 % or lowe , the XRD method can pro ide a lmit of det ection of 0,0 wt% an the l mit of

q antification can be as low as 0,0 wt% When the matrix r d ction is les efe tive an the r sid al

ratio is o e 1 % of the initial 1 0 mg sample, a sub-divided 1 mg t o 1 mg sample is taken from the

r sid al sample In the case w he e noneor ve y lt le of the matrix is r d c d, the l mit of det ection can

inc ease up t o a pro imat ely 0,1 % an the lmit of q antif ication can inc ease up t o a pro imat ely

0,3 % When matrix r d ction achievesa r sid al ratio of a pro imat ely 3 % of the original weight, the

l mit of q antif ication is a pro imat ely 0,1 % These l mit of det ection an q antification ar furthe

degraded if int erfe enc X-ra peaks or high b ckgrou d X-ra int ensities from matrix mat erials ar

A ir quality — Bulk materials —

Part 3:

This p rt of ISO 2 2 2 is primariy int en ed for q antitative analy sis of samples in w hich asbest os has

be n identif ied at es imat ed mas fractions lowe than a pro imat ely 5 % b weight

This p rt of ISO 2 2 2 ext en s the a pl ca i ity an l mit of det ection of q antitative analy sis b the

use of simple proc d r sof ashing and/ r acid tr atment prior t o XRD q antification

This p rt of ISO 2 2 2is a plca le t o the asbest os-containing mat erials identified in ISO 2 2 2-1 The

folowing ar ex mples of sample matric s:

a) any buiding mat erials in w hich asbest os was det ect ed b the analy sis in ISO 2 2 2-1;

b) r si ent flo r ti es, asphaltic mat erials, ro fing felt an any othe mat erials in w hich asbest os is

embed ed in an org nic matrix an in w hich asbest os was det ect ed w hen using ISO 2 2 2-1;

c) wal and c i ng plast ers, with or without a gr g t e, in w hich asbest os was det ect ed w hen using

ISO 2 2 2-1

If non-asbes iform se pentine or non-asbes iform amphib le mine als ar inclu ed in the matrix, the

XRD peaks that ar as umed t o be “ pos ible peaks of asbest os” wi l r pr sent these mine als This

method is not for a plcation t o natural mine als that ma contain asbest os or any prod ct that

incorporat e such natural mine als This method is int ended only for a plcation t o buiding mat erial

samples that contain delbe at ely ad ed comme cial grade asbest os inclu ing tr molt e asbest os

This p rt of ISO 2 2 2 is int en ed for use b analy st w ho ar fami ar with X-ra difraction methods

an the othe analytical proc d r s spe ified in the R efe enc s [5]an [6] It is not theint ention of this

p rt of ISO 2 2 2 t o pro ide b sic ins ruction in the fun amental analytical proc d r s

2 Normati ve r eferences

The folowing document , in w hole or in p rt, ar normatively r fe enc d in this document an ar

in ispensa le for it a pl cation F or dat ed r fe enc s, only the edition cit ed a pl es F or u dat ed

r fe enc s, the lat es edition of the r fe enc d document ( inclu ing any amen ment )a pl es

ISO 2 2 2-1:2 1 , Air q alt y — B ulk materials — Part 1: S mpln a d q altati ve dete min tio o

asbes tos in c omme c ial b lk mate ial s

ISO 2 2 2- 2:2 14, Air q alt y — B ulk mate ial s — Part 2 : Qu ntitati ve dete min tio o asbes tos b

gravimetric a d mic rosc opic al meth ds

3 Terms and definitions

F or the purpose of this document, the folowing t erms an def initions a ply

t erm a pled t o a group ofsi cat e mine als belonging t o the se pentine an amphib le groups w hich

ha e c y stal z d in the asbes iform ha it, causing them t o be easiy sep rat ed int o long, thin, flexible,

s rong f ibr s w hen c ushed or proc s ed

Not e 1 to entry: T e C emical Abstracts S rvice R egistry Numb r of the most common asb st os varieties are:

chry sotile (1 0 1 2 – ), c ocidolite (1 0 1 2 –4), gru erite asb stos (Amosite) (1 172–73 5), anthop yl ite

asb st os (7 5 6–67 –5), tremolite asb st os (7 5 6–68 6)an actinolite asb stos (7 5 6–6 –4).Other varieties

of asb stiform amp ib le, such as richt erite asb stos an winchite asb stos

[2 ]

, are also fou d in some prod cts

such as vermiculite an talc

gravimetric matrix reductio

proc d r in w hich cons ituent of a mat erial ar sele tively dis olved or othe wise sep rat ed, lea ing

a r sid e in w hich any asbest os pr sent in the original mat erial is conc ntrat ed

[ SOURCE:ISO 2 2 2- 2:2 14, 3.2 ]

3.5

integral intensity

peak ar a cou t ( int egral cou t)of a designat ed XRD peak aft er subtracting the b ckgrou d ar a

3.6

l mit of detection

weight of asbest os on a filt er d sample w hich prod c s a det ecta le XRD peak u de the measur ment

con itions shown in An ex A

Not e 1t o entry: Expres ed as a per enta e mas fraction of the original sample

3.7

l mit of quantificatio

weight of asbest os on a f ilt er d sample for w hich the int egral int ensity ofthe XRD peak can be measur d

Not e 1 to entry: Expres ed as a per enta e mas fraction of the original sample Limit of q antif ication is

conventional y e pres ed as thre times the limit of detection

3.8

matrix

mat erials in a bulk sample within w hich f ibr s ar dispe sed

[ SOURCE:ISO 2 2 2-1:2 1 , 2.3 , modif ied]

3 9

original sample

sample taken from a buiding mat erial prod ct w hich was analy sed using ISO 2 2 2-1

analytical sample r maining aft er tr atment with formic acid or othe a pro riat e tr atment t o r mo e

matrix cons ituent

This p rt of ISO 2 2 2 is for a plcation t o buiding mat erial samples an the targ et rang e for the mas

fraction of asbest os is from 0,1 % t o 5 % In this method, gra imetric matrix r d ction proc d r s

ar used t o r d c the matrix cons ituent an int erfe enc mine als in a 1 0 mg commin t ed sample

The e is no up e l mitation for q antif ication;this XRD method can q antify asbest os upt o 1 0 % The

lowe en of the rang e depen s on the r sid al ratio o tained b the matrix r d ction methods When

the matrix r d ction method is not efe tive an 1 0 % of the sample r mains, the l mit of det ection

(LOD ) is 0,1 % an the lmit of q antif ication (LOQ) is 0,3 % When lowe v lues of the r sid al ratio

can be achieved, the LOD an LOQ can de r ase t o 0,0 % or smale Howeve , the LOD an LOQ that

can be o tained d ring analy ses of actual buiding mat erials also depen s on the X-ra peak sele t ed

for analy sis an w hethe int erfe enc X-ra peaks or high-int ensity b ckgroun from matrix mat erials

ar pr sent

5 Limit of quantification

This XRD method can det ect 0,0 mg asbest os in a 1 mg sample on a filt er of ar a 2 cm

2

an q antify

0,0 mg asbest os in a 1 mg sample on a f ilt er of ar a 2 cm

2

The ma imum sample weight for w hich

the X-ra a sorption can be cor e t ed is a pro imat ely 1 mg on a filt er of ar a 2 cm

2

In this method,

gra imetric matrix r d ction proc d r s ar used t o r d c the matrix cons ituent an int erfe enc

mine als in a 1 0 mg commin t ed sample When a 1 0 mg sample containing 0,0 mg asbest os is

r d c d b matrix r d ction t o 1 mg (r sid al ratio: 1 % ), the XRD method can det ect the 0,0 mg

asbest os on the filt er C nseq ently, 0,0 % asbest os in the original sample of 1 0 mg can be det ect ed

In this case, the LOD an LOQ of the XRD method ar a pro imat ely 0,0 % and 0,0 %, r spe tively

When the matrix r d ction methods ar les efe tive an mor than 1 mg of the sample r mains,

the LOD an LOQ can inc ease up t o 0,1 % an 0,3 %, r spe tively An LOQ of a pro imat ely 0,1 % is

achieved w hen the sample is r d c d t o a pro imat ely 3 % b the matrix r d ction methods

The LOD an LOQ that can be achieved d ring analy sis of actual buiding mat erials depen on the

folowing:

a) the ty e of asbest os being analy sed;

b) w hethe a se on ary peak is being measur d be ause the primary peak has o e la ping peaks;

c) the dife enc s betwe n the sour e of asbest os in the sample an that of the s an ard asbest os

r fe enc mat erial used t o de ive theworking curve;

d) the ext ent t o w hich gra imetric matrix r d ction can r mo e matrix mat erials;

e) thepr senc of int erfe enc X-ra peaks or high b ckgrou ds from matrix mat erials;

f) thep wer of the X-ra g ene at or an the ty e of X-ra det ect or used

6 Symbols and abbr eviated terms

asbest os mas fraction of one sub-r sid al sample (% )

w asbest os mas fraction in buiding mat erial prod ct or othe prod ct ( % )

r weight los ratio aft er heat tr atment for a sample containing org nic cons ituent

V int egral X-ra difraction int ensity in cou t

s

i

s andard deviation of int egral X-ra difraction int ensity of i times

a gradient of working curve

lower l mit of det ermination of asbest os mas fraction (% )

7 Requir ements for quantification

A pr r q isit e for use of this p rt of ISO 2 2 2 is that the sample shal ha e be n ex mined using

ISO 2 2 2-1

Q uantification of asbest os beyon the es imat e of mas fraction achieved using ISO 2 2 2-1 ma not

be ne es ary, depen ing on the a pl ca le r gulat ory lmit for definition of an asbest os-containing

mat erial, the v riety of asbest os identified an w hethe the sample can be r co niz d as a man factur d

prod ct Common r gulat ory definitions of asbest os-containing mat erials rang e from “ pr senc of any

asbest os” t o > ,1 %, > ,5 % t o > % b mas fraction of one or mor of the r gulat ed asbest os v rieties

F or many bulk samples analy sed using ISO 2 2 2-1, it is intuitively o vious t o an ex e ienc d analy st

that the asbest os mas fraction far ex ce ds these mas fraction lmit In the case of these ty es of

samples, an ex e ienc d analy st can also confidently det ermine that the asbest os mas fraction is

wel below these r gulat ory lmit Mor pr cise q antif ication of asbest os in these ty es of samples

is un e es ary, sinc a mor pr cise an signif icantly mor ex ensive det ermination of the asbest os

mas fraction wi l neithe chang e the r gulat ory s atus of the asbest os-containing mat erial nor any

subseq ent de isions conc rning it tr atment Annex C show s a ta ulation of mos asbest os-containing

mat erials, the v riety of asbest os used in these mat erials an the rang e of asbest os mas fraction that

ma be pr sent An ex C also in icat es w hethe , in g ene al, the es imat e of asbest os mas fraction

pro ided b the use of ISO 2 2 2-1 is sufficient t o es a lsh the r gulat ory s atus of the mat erial or

w hethe q antification of asbest os b this p rt of ISO 2 2 2 is ne es ary The analys should r fe t o

An ex C for guidanc on the pro a le asbest os mas fractions in spe ific clas es of prod ct an the

o timum analytical proc d r t o o tain a r la le r sult

Asbest os was neve delbe at ely incorp rat ed for any fu ctional purp se int o comme cialy

man factur d asbest os-containing mat erials at mas fractions lowe than 0,1 % A ccordingly, if any

one or mor of the comme cial asbest os v rieties (chry soti e, amosit e, c ocidolt e or antho hy llt e)

is det ect ed in a man factur d prod ct, the as umption can be made that asbest os is pr sent in the

prod ct at a mas fraction ex ce ding 0,1 % The efor , if the r gulat ory def inition of an asbest

os-containing mat erial in a jurisdiction is eithe “ pr senc of any asbest os” or gr at er than 0,1 %, then

det ection of one or mor of the comme cial asbest os v rieties in a r co niza le man factur d prod ct

aut omaticaly defines the r gulat ory s atus of the mat erial If the r gulat ory definition is eithe 0,5 %

or 1 % an the mas fraction of asbest os is es imat ed t o be lowe than a pro imat ely 5 %, then mor

pr cise q antification is ne es ary t o guarant ee the r gulat ory s atusof the mat erial

Det ection of tr mol t e, actinolt e or richt erit e /winchit e in a mat erial does not alow any as umptions

t o be made r g rding the asbest os mas fraction be ause these asbest os v rieties we e, in g ene al, not

delbe at ely ad ed t o the prod ct Rathe , they g ene aly oc ur as ac es ory mine als in some of the

cons ituent used t o man factur prod ct Sinc the non-asbes iform analo ues of the amphib les

ar not g ene al y r gulat ed, it is also ne es ary t o disc iminat e betwe n the asbes iform an

non-asbes iform analo ues of these mine als When pr sent, these amphib le mine als oft en oc ur as

mixtur s of the two analo ues in in us rial mine als

It is not p s ible t o spe ify a single analytical proc d r for al ty es of mat erial that ma contain

asbest os be ause the rang e of matric s in w hich the asbest os ma be embed ed is ve y dive se Some

mat erials ar amena le t o gra imetric matrix r d ction an some ar not

The r q ir ment for q antification beyon that achieved in ISO 2 2 2-1 ar summariz d in Ta le 1

Table 1 — Summary of requirements for quantificatio of asbestos in bulk samples

Ty e of mat erial

R egulat ory control l mit

“Any asbest os”

If an commer ial asb st os variety is

detected, no further q antif ication is

req ired

If asb stos is detect ed at an estimated

mas fraction of < %, more precise

q antif ication is req ired t o esta lish

If asb st os is detected at an estimated mas fraction of

< %,more precise q antif ication is req ired to esta lish

the re ulat ory

status of the mat erial

8 A pparatus and r eag ents

8.1.1 S mple c ommin tio equipment

An a at e mortar an pes le, or a mi l, is r q ir d for grinding of samples t o suita le siz s for XRD

measur ment This eq ipment shal be used in a neg tive pr s ur HE A-filt er d d s ho d with a

minimum fac velocity of 0,4 m/s

8.1.2 Negati ve pres ure, HEPA-fitered dust hoo

A HEPA-f ilt er d d s ho d with a minimum fac velocity of 0,4 m/s is r q ir d t o ac ommodat e

eq ipment or commin tion of samples

8.1.3 A nal ytical balanc e

An analytical b lanc with a r ada i ty of 0,0 0 0 g (0,0 mg) or lowe isr q ir d

8.1.4 Mufle furnac e

F or ashing of samples t o r mo e int erfe enc org nic cons ituent , a mufle furnac with a minimum

t empe atur of 5 0 °C, an a t empe atur s a i ty of ± 0 °C, is r q ir d

8.1.5 Ultrasonic cle ner

An ultrasonic cleane is r q ir d for dispe sion of r sid al samples befor car ying out the f iltration

proc s

8.1.6 Glas fitratio as embl y (25 mm diameter )

A glas f iltration as embly with a v cu m f iltration flask is r q ir d

8.1.7 General laborator y supples

The folowing sup les an eq ipment, or eq iv lent, ar r q ir d:

a) glas ine p pe she t , a pro imat ely 1 cm × 1 cm, for ex mination of the original samples an

thecommin t ed samples;

b) disp sa lealuminium or plas ic weighing cups, a pro imat ely 3 cm t o 5 cm in diamet er;

c) samplng ut ensis, inclu ing twe z rs, ne dles an othe s;

i) polyt etrafluoroethy lene (PFTE) co t ed glas fibr filt ers, 2 mm diamet er

8.1.8 X-ray difractometer

An X-ra p wde difract omet er using Bra g -Br ntano (p ra-focusing) g eometry is r q ir d an

eq ip ed as folow s:

a) co pe targ et X-ra tube, with a powe of 1,6 k W or highe ;

b) sample spin e t o impro e p rticle s atis ics;

c) nickel f ilt er, gra hit e monochromat or or othe X-ra o tics with simiar or bett er ene g r solution

t o o tain a monochromatic X-ra beam (CuK α lne);

d) high-efficiency p sition-sensitive X-ra det ect or, e.g position-sensitive semicon uct or det ect or

NOTE Due to the low det ection limits req ired, older ty e s intilation or proportional cou t er are not

recommen ed

8.2 Reag ents

8.2.1 Dust-free distiled water

8.2.2 C nc entrated formic acid, r eag ent g r ade.

8.2.3 Sodium h ydrox ide pelets, r eag ent g r ade

8.2.4 Isopr opyl alc ohol, r eag ent g rade

9 Q uantitati ve X RD method and principle

9.1 Quantitati ve X RD methods using an ex ternal standard

Sinc the int ensity of an XRD peak depen s on the amou t of a c y stal ne subs anc in a sample, the

mas fraction of a c y stal inesubs anc can be det ermined b measur ment of the difraction int ensity

Howeve , as the dif raction int ensity is influenc d not only b the mas fraction ofthe c y stal ine

mat erials but also b the a sorption of the X-ray s b the sample it elf, the measur d int ensity should

be cor e t ed for this a sorption t o ena le q antif ication The wel-k own q antitative methods for

cor e ting the a sorption in XRD of powde samples ar the int ernal s an ard method an the s an ard

ad ition method

[5][6]

The analytical ac uracies of thesemethods ar high for mos subs anc s; howeve ,

for f ibrous particles, such as asbest os, ac uracy can sufe be a use the f ibr orientation v ries gr atly

an this afe t the difraction int ensity An ext ernal s an ard method using a subs rat e s an ard was

develo ed for smal samples of p wde

[7]

an it was simplfied b mou ting the sample on a co pe

foi an measuring the difraction int ensity from the foi with and without the sample in plac A

cor e tion fact or can then be calculat ed from the o se ved att en ation ofthe difraction peak from

Then, a t echniq e was develo ed in w hich a sample of airb rne p rticulat e is cole t ed on

a p lycarbonat e f ilt er an the particulat e is r -dep sit ed on a sive membrane f ilt er

[1 ][1 ][1 ]

It was

r co niz d that a fibrous sample dep sit ed on a thin filt er yields a s a le an r prod cible difraction

int ensity d e t o the fact that fibr s ar orient ed paralel t o the f ilt er surfac

[1 ][14]

A thin f ilt er asbest os

sample is plac d on a subs rat e metal plat e an the dif raction int ensities from b th asbest os on

the f ilt er and the subs rat e metal plat e can be measur d be ause a thin filt er does not significantly

a sorb X-ray s The t ech iq e using a membrane filt er of mix ed est ers of c lulose an a subs rat e zinc

plat e was develo ed for measur ment of airb rne q artz samples

[1 ]

These XRD methods using a

subs rat e metal filt er or a thin filt er on a subs rat e metal plat e ar emplo ed b v rious org nizations

for q antitative analy sis of asbest os an c y stal ine si ca

[16][17][18][1 ]

The subs rat e s an ard mas

a sorption cor e tion method is emplo ed in this part of ISO 2 2 2

9.2 Summar y of the quantitati ve method

The XRD method spe if ied in this part of ISO 2 2 2is a plca le t o the q antitative analy sis of asbest os

in asbest os-containing samples as identif ied b ISO 2 2 2-1 The o se ved difraction int ensities of al

c ys al ne subs anc s in a sample ar att en at ed as a r sult of X-ra a sorption b the sample matrix

The att en ation of the difraction int ensities from a c y stal ine subs anc can be cor e t ed using a

cor e tion fact or, b sed on the r d ction of the difraction int ensity of the subs rat e s an ard mat erial,

as shown in An ex B The difraction int ensities from asbest os in the working curves shown in Annex A

ar those that ha e be n cor e t ed for the att en ation d e t o X-ra a sorption The weight of mat erial

on a f ilt er (2 cm

2

) should be les than 1 mg

[1 ][14]

F or weight up t o 1 mg, u de o timum con itions,

the difraction int ensity ( int egral int ensity) of asbest os can be measur d t o as low as 0,0 mg f ilt er

(2 cm

2

),

[1 ][14]

pro ided that int erfe enc X-ra peaks or high b ckgrou d from matrix mat erials ar

not pr sent F or the q antif ication of asbest os in bulk mat erials b this part of ISO 2 2 2, gra imetric

matrix r d ction methods ar used t o r mo e as much as p s ible of the matrix cons ituent of the

sample, so that any asbest os is conc ntrat ed t o a highe mas fraction in the final r sid al sample

A summary of the q antitative proc d r is as folow s

a) An a pro riat e sub-sample (0,5 g or mor ) is taken from the original sample, in w hich asbest os has

alr ady be n identif ied b ISO 2 2 2-1

b) The sample is grou d an sieved through a 2 0 μm mesh sieve t o pr p r a commin t ed sample It

is ne es ary t o grin the sample in this wa in orde t o o tain high q alty data b XRD analy sis

Depen ing on the matric s, such as org nic component , it ma be ne es ary t o ash the sample

befor grin ing

c) A sub-sample of 1 0 mg is taken from the commin t ed sample and tr at ed with formic acid an / r

ashing and the r sid e is filt er d ont o a membrane f ilt er, such as a PTFE-co t ed glas fibr f ilt er,

a si ve f ilt er or a p ly iny lchloride (PVC) f ilt er Aft er weighing, if the r sid al ratio is lowe than

1 %, the filt er d r sid al sample is used for the q antitative analy sis of asbest os b the XRD

method Prior t o the q antitative analy sis, a q altative XRD scan is r commended t o ex mine the

difraction int ensities of any asbest os mine als an also t o che k w hethe peaks from any othe

mine als in the matrix int erfe ewith them

NOT For some la ging samples composed of calcium silicates, a chemical tre tment using formic

acid is sometimes not efective an more than 1 % resid e remains aft er the tre tment In this case, an

alkali tre tment using 2 % sodium hydro ide solution is efective to red ce the matrix T e proced re is

des rib d in 1 3

d) When the r sid e from the matrix r d ction b ashing an tr atment with formic acid or alkal

ex ce ds 1 %, take a sub-r sid al sample of 1 mg t o 1 mg from ther sid al sample an trans e

it ont o a filt er The ma imum amou t of sample on a membrane filt er is l mit ed t o 1 mg d e t o

l mitations of the mas a sorption cor e tion

e) When matrix r d ction of a 1 0 mg commin t ed sample yields a r sid al sample of 1 mg (r sid al

ratio: 1 % ), the XRD method can pro ide a lmit of det ection (LOD ) of a pro imat ely 0,0 % an

a l mit of q antification (LOQ) of a pro imat ely 0,0 % When the r sid al ratio is highe , the LOD

can inc ease up t o 0,1 % an the LOQ can inc ease up t o 0,3 % A LOQ of a pro imat ely 0,1 % is

achieved w hen matrix r d ction r sult in a r sid al ratio of a pro imat ely 3 % Howeve , the

LOD an LOQ that can be o tained d ring analy ses of actual buiding mat erials also depen s on the

X-ra peak sele t ed for analy sis an w hethe int erfe enc X-ra peaks or high-int ensity b ckgrou d

from matrix mat erials ar pr sent

9.3 Preparation of wor king curve and measurement

Measur the difraction int ensity from the subs rat e s an ard metal c plat e (zinc, aluminium, et c ), t o

w hich is at ached a blan f ilt er ( he same ty e of filt er t o be used for the pr p ration of the working

curves)

Asbest os s an ards (1 2, Not e 1) in the rang e betwe n 0,0 mg an 5 mg ar dep sit ed on the f ilt ers

an the each f ilt er is plac d on a subs rat e s an ard zinc plat e The difraction int ensities from zinc an

asbest os ar then measur d for each f ilt er

The difraction int ensity of a zinc plat e t o w hich a f ilt er containing asbest os is at ached wi be

att en at ed comp r d with that of zinc plat e t o w hich a blan f ilt er is at ached From this att en ation

ratio, the cor e tion fact or, K

f, is calculat ed using F ormula (B.1) The a sorption-cor e t ed difraction

int ensity of the asbest os is calculat ed using F ormula (B.2)

The working curve is o tained b plot ing the weight of asbest os in the rang e between 0,0 mg filt er

(2 cm

2

) an 5 mg filt er (2 cm

2

) on the a scis a an the r spe tive a sorption-cor e t ed difraction

int ensities of the asbest os on the ordinat e

F or the q antitative measur ment of asbest os in a sample, the weight of asbest os (mg) cor esp n ing

t o the o se ved difraction int ensity can be o tained b comp rison of the a sorption-cor e t ed

difraction int ensity of the asbest os in the sample with the difraction int ensity shown in the working

curve The asbest os mas fraction (% ) is then calculat ed from the ratio of the weight of asbest os an

the weight of the original sample, i.e 1 0 mg

9.4 Interferenc e minerals

Befor q antitative analysis, it is ne es ary t o inves ig t e w hethe any int erfe enc mine als ar

pr sent from w hich difraction peaks a pear at or near those of chry sotie or amphib le ( e Ta le 2)

Pr cise che ks of difraction p tt erns for p t entialy o e la ping peaks can es a l sh the exist enc of

these int erfe enc mine als When a difraction peak from an int erfe enc mine al a pears at or near

that used for det ermination of asbest os, chemical tr atment (using acid an / r alkal) ma efe tively

dis olve those int erfe enc mine als an also r d c the matrix When int erfe enc mine als can ot

be r mo ed efe tively b such tr atment, it wi l be ne es ary t o use a se ondary difraction peak of

asbest os for the q antif ication ( e 1 1 an 1 2) When a se on ary peak is emplo ed for q antitative

analy sis, the q antif ication lmit of the measur ment is sometimesdegraded

10 Preparation ofcomminuted sample

The v rious sample pr p ration proc d r sdesc ibed in ISO 2 2 2- 2 for the q antif ication of asbest os

b PLM can also be used for this XRD method

Commin tion of asbest os-containing mat erials can g ene at e airb rne asbest os f ibr s an is the efor

hazardous A ccordingly, the pr p ration of samples shal be car ied out in a HEPA-f ilt er d containment

a paratus

10.1 Preparation of comminuted sample from orig inal sample

Pr p r the commin t ed samples from the original samples as folows

a) Original samples analysed b the q altative analy sis in ISO 2 2 2-1 ar pulveriz d int o p wde

The commin tion proc d r shal be asfolow s

1) If the original sample is hard, sc a e mat erial from the side surfac using a k ife or othe

a pro riat e t ool Obtain a pro imat ely 0,5g of sub-sample befor put ing it in a pulve iz r

2) F or the commin tion, use a mortar (p r elain mortar, a at e mortar or alumina mortar,

et c ), W iley mi , an ultra-c ntrifug l cutt er, a vibrating mi l, a b l mi or othe a pro riat e

pulve izing devic

3) F or some r si ient mat erials, such as asphaltic an viny l mat erials, ashing at a t empe atur

lowe than 45 °C for a pe iod ofa pro imat ely 1 h is efe tive for r mo al of the org nic

cons ituent ( e ISO 2 2 2- 2:2 14, 6.2) Aft er ashing, the sample is mi led using an a at e

mortar or a vibrating mi l

b) Take car t o a oid ex ces ive commin tion

c) A smal p rtion of the commin t ed sample is p s ed through a 2 0 μm mesh sieve A dditional

commin tion an sieving is car ied out u ti the entir commin t ed sample has be n p s ed

through the sieve To faci itat e sieving, wet sieving using wat er or iso ro y l alcohol has be n fou d

t o be efe tive Al of the sieved sub-samples ar combined t o comprise the commin t ed sample

10.2 He t treatment of c omminuted samples that c ontain or ganic c onstituents

The analys shal r fe t o the method desc ibed in ISO 2 2 2- 2:2 14, 1 4

The tr atment of a commin t ed sample ha ing org nic cons ituent shal be as folows

a) Plac each of the thr e ran omly-sele t ed sub-samples of a out 0,2 g each int o a pr -weighed

c ucible (m

c

b) Weigh the c ucible with the combined sample (m

a)

c) Plac the c ucible in a muf le furnac set at a tempe atur of (45 ± 1 ) °C an heat for

a pro imately 1 h

d) Aft er heating, lea e the c ucible an cont ent t o co l in clean con itions an weigh (m

b) Then

calculat e the weight los ratio (r) ac ording t o F ormula (1):

is the weight of the original sample befor heating (g);

m is the weight of the original sample aft er heating (g)

10.3 Pretreatment for preparation of r esidual samples

The pr p ration of r sid al samples for q antitative det ermination of asbest os shal be car ied out as

folows (r fe t o the method desc ibed in ISO 2 2 2- 2:2 14, 1 3)

a) Weigh a 2 mm diamet er PTFE-co t ed glas f ibr filt er (m

1) (he eaft er r fe r d t o as “f ilt er” an

mou t it on a subs rat e s andard metal plat e (zinc, aluminium, et c ) in the g oniomet er of the X-ra

difract omet er and measur the difraction int ensity of the metal through the filt er

b) Weigh 1 0 mg of the commin t ed sample pr cisely (t o the near s 0,0 0 1 g) (m

2: weighed v lue

of commin t ed sample) an put it in a conical flask A dd 2 ml of 2 % formic acid an 40 ml of

dis i led wat er an dispe se the sample in solution b using an ultrasonic cleane for a out 2 min

c) P t each flask int o a wat er b th at a t empe atur of 3 °Can shake the flask for 1 min

d) Fi t er the sonicat ed sample on t o a pr -weighed f ilt er using a v cu m f iltration a p ratus

e) Aft er drying the f ilt er with the r sid al sample at a out 8 °C, weigh the filt er (m

3) The dife enc

betwe n m

3

1

is the mas of the r sid al sample

f) The r sid al ratio ( % )is calculat ed using F ormula (2):

When the r sid al ratio ex ce ds 1 %, a sub-r sid al sample shal be pr p r d in ac ordanc with 1 4

A tr atment with alkal is sometimes ne ded t o r d c matric s in buiding mat erials consis ing of

calcium si cat es(e.g la ging) The proc d r is as folow s

a) Weigh the f ilt er (m

1) an measur the difraction int ensity of the b se metal plat e as desc ibed in

1 3 a)

b) Weigh a pro imat ely 1 0 mg of the commin t ed sample consis ing of calcium si icat e la ging

(m

2

) an plac it in a 1 0 ml conical flask A dd 60 ml of 2 % sodium hydro ide solution an

heat it t o r duc the v lume t o a pro imat ely 5 ml Alow the flask an cont ent t o co l t o ro m

t empe atur

c) Fi t er the suspension on t o a pr -weighed f ilt er using a v cu m filtration a paratus Aft er the

f iltration, wash the r sid es on the filt er using 2 % formic acid an wat er

d) Aft er drying, weigh the filt er (m

3) The dife enc (m

3

− m

1)is the weight of the r sid al sample an

the r sid al ratio (% ) is calculat ed using F ormula (3):

NOT 1 T in P F -co t ed glas fibre filt er are freq ently used for the me surement of airb rne d st in

working en ironments This ty e of filt er rarely a sorbs moisture, it provides ex celent weight sta ility Glas fibre

filt er prod ce a larg e an bro d X-ray b ckgrou d at arou d 2 ° t o 2 ° at 2θ for the C K α line, w hile the dia nostic

difraction pe ks of asb st os ap e r at arou d 1 ° t o 1 ° an arou d 2 ° t o 3 ° at 2θ w here the X-ray b ckgrou d

is very low In ad ition, P F -co t ed glas fibre filt er are e tremely thin an highly transparent t oX-ray s

NOTE 2 In this XRD me surement method, the resid al sample af er the matrix red ction tre tment is f ilt ered

ont o a P F -co ted glas f ibre f ilter an the f ilter is dried b fore weighing The f ilter sample is mou ted directly

in the g niometer of the X-ray difract omet er P F -co ted glas f ibre f ilter are convenient or me suring b th

the weights of resid al samples an the int ensities of difraction pe ks from substrate stan ard metals an

asb stos

Othe membrane f ilt ers such as sive , p ly iny lchloride (PVC) or mix ed est ers of c lulose (MEC) ma

also be used

10.4 Preparation of sub-residual samples

F or r sid al samples ex ce ding 1 mg, pr par sub-r sid al samples as folow s

a) Take a sub-r sid al sample of 1 mg t o 1 mg from the r sid al sample an dispe se it in dis i led

wat er using the ultrasonic cleane

b) Using a v cu m filtration a p ratus, f ilt er the sonicat ed sub-r sid al sample ont o a pr -weighed

PTFE-co t ed glas fibr f ilt er an dry the f ilt er at a out 80 °C

c) Aft er drying, weigh the f ilt er and subtract the weight of the blank filt er t o o tain the mas of the

sub-r sid al sample (m

3: weight of the sub-r sid al sample)

11 Difraction peaks for anal ysis ofasbestos and ofinterferenc e materials

11.1 Difraction peaks for quantitati ve anal ysis of asbestos

The difraction peaks used for the q antif ication of asbest os ar in icat ed in Ta le 2, in w hich mine al

names r lat ed t o asbest os, the Int ernational Cent er for Difraction Data (ICDD ) f ile n mbe s, d-spacing

(Å), difraction angle for CuK α X-ra s, int ensity ( I/I

1) an r fle tion in ic s (h l) ar shown Each

difraction peak has a smal fluctuation in the angle (2θ) an the int ensity ( I/I

1) in actual samples

Wheneve p s ible, the main difraction peaks at 1 ,1° for chry soti e an at 1 ,4°t o 1 ,7° for amphib les

ar used for q antitative analy sis When the peak of a matrix mine al int erfe es with the main peak

from chry sotie or amphib le, these on ary dif raction peaks at 24,4° for chry sotie an 2 ,4° t o 2 ,2°

for amphib lesar used

When a sample contains two or mor kin s of asbest os, spe ial proc d r s ar r q ir d The v rieties of

asbest os pr sent ar k own aft er completion of the analy sis b ISO 2 2 2-1 F or mixtur sof chry soti e

an any v riety of amphib le asbest os, the in ivid al conc ntrations can be measur d F or mixtur s

of dife ent v rieties of amphib le asbest os, the e ar calbration difficulties If the mixtur consis s of

amosit e an c ocidolt e, the calbrations ar sufficiently simiar that the difraction peaks a pearing

near 1 ,5° or 2 ,6° can be int erpr t ed as the sum of the mas fraction of the two kin s of amphib le

asbest os F or mixtur s of amphib les with dife ing calbrations, it is not p s ible t o q antify the

r sult

Table 2 — Dif raction pe ks used for q antitative analy sis of asbestos

Amp ib les Gru erite (Amosite)

Rie eckite (Crocidolit e)

Cop er target, K lne

ICD Fie No Dif a tion data c mpied b Joint Commite on Powder Difra tion Stan ards-nternational Center for

Dif a tion Data, Mineral Powder Dif a tion Fie Data Bo k 19 0

The difraction patt erns of r fe enc asbest os samples ar shown in Figur 1 a) t o e) W ith the ex ception

of a q artz peak in Figur 1 b)(amosit e) an Figur 1 c)(c ocidolt e), al difraction peaks in Figur 1 b)

t o e) ar at ribut ed t o those of the amphib le asbest os of each ty e The difraction peaks used for

q antification ar marked b a double cir le (he main peak) an a single cir le ( he se on ary peak)

Tr mol t e an actinol t e ar membe s of a sold solution se ies, the comp sition of w hich v ries with

the conc ntration of iron The XRD p tt ern o tained from an u k own sample, the efor , ma dife

from the patt ern exhibit ed b each en -membe mine al shown in the ICDD/JCPDS f ile The efor ,

tr molt e an actinol t e ar cat eg oriz d as tr molt e /actinolt e ex cept w hen the patt ern fit eithe that

of tr molt e or actinolt e as lst ed in the ICDD/JCPDS f ile

a) Chry sotie (JAWE 1 1;Coalng mine, USA)

b) Amosite (JAWE 21 ; Transv aal mine, South Africa)

Al difraction peaks ex cept the q artz peak (Q) in Figur 1 b) ar at ribut ed t o those of amosit e

c) Crocidol te (JAWE 311;Transv aal mine, So th Africa)

Al difraction peaks ex cept the q artz peak (Q) in Figur 1 c) ar at ribut ed t o those of c ocidol t e

d) Tremolte asbestos (JAWE 4 1; Yama a mine, Japan)

Al difraction peaks that a pear d in Figur 1d)ar at ribut ed t o those of tr molt e

e) Anth p y ll te asbestos (JAWE 5 1; a mine in Afghanistan)

Al difraction peaks that a pear d in Figur 1e)ar at ribut ed t o thoseof antho hy llt e

Figure 1 — XRD patterns of typical asbestos

11.2 Interferenc e minerals

11.2.1 Pos ible interfer enc e minerals

When a difraction peak of a matrix mat erial o e la s or adjoins the f irs difraction peak of asbest os,

the se on ary peak of asbest os should be used The efor , befor q antitative analy sis, the XRD

p tt ern of the sample should be ex mined t o det ermine if any difraction peaks of int erfe enc mine als

o e la or adjoin with the dia nos ic difraction peaks of asbest os When a dif raction peak from a

matrix mine al o e la s the main peak of chry sotie (1 ,1° or amphib le asbest os (1 ,4° t o 1 ,7° , the

se on ary difraction peak of 24,4° for chry sotie or of 2 ,4° t o 2 ,2° for amphib le asbest os is used for

q antitative analy sis, using a r sid al or sub-r sid al sample When chry sotie and chlorit e co-exis in

a sample, the use of the se ondary difraction peak of chry soti e is r commen ed for q antif ication as

chlorit e does not int erfe e with this peak The use of se on ary asbest os peaks for q antif ication can

lead t o highe lmit of q antification than for primary difraction peaks

Mine als that show a difraction peak near the dif raction angle of 1 ,1° (2θ) of chry sotie ar the

se pentine mine als lzardit e an antig orit e, ka l n mine alsinclu ing haloy sit e, chlorit e (clnochlor ),

sepiol t e, ve micult e, synthetic mine als of g psum (C SO

4) an hydrat ed calcium si cat es such as

xonotlt e or t obe morit e, as shown in Ta le 3 The difraction angle of 1 ,1° for chry sotie is slghtly

dife ent from the peaks of g psum (1 ,7° , x onotlt e (1 ,7° , ka lnit e (1 ,4° , chlorit e (1 ,4° an

sepiolt e (1 ,8° Depen ing on the r lative mas fractions of chry soti e an the int erfe enc mine al,

the peak from chry sotie can ot alway s be disc iminat ed from those originating from these mine als

w hen they ar pr sent Ve micul t e used in buiding mat erials has usual y be n heat ed at a t empe atur

of a out 7 0 °C or mor , ca using the b sal sp cing of 14,5 A t o be r d c d t o 1 A, the efor the peak at

7,1 A (004 ) from ve micult e is no long er pr sent

The e a pear t o be no dif raction peaks of mine als showing angles simiar t o 1 ,4°t o 1 ,7° (2θ) of the

main peaks of amphib le, but the difraction peaks of calcit e (2 ,4° , x onotlt e (2 ,0° an t obe morit e

(2 ,0° a pear near the se ondary peaksofamphib le The efor , it isbett er t o use the main difraction

peaksnear 1 ,5° (2θ)for the q antitative analy sisof amphib le

Table 3 — Dif ractio pe ks of q antitative analy sis of asbestos and pos ible interference

minerals in buiding pro ucts

Minerals ICDD File

Asb stos Gru erite (Amosit e)

Rie eckit e (Crocidolite)

Pos ible intererenc minerals of chrysotie an amp ibole asbes os, respe tively

ICD Fie No Dif a tion data c mpied b Joint Commite on Powder Difra tion Stan ards-nternational Center for

Dif a tion Data, Mineral Powder Dif a tion Fie Data Bo k 19 0

11.2.2 Mas reductio tr eatments for dis ol ving interferenc e minerals

The gra imetric matrix r d ction methods desc ibed in ISO 2 2 2- 2 ar useful t o r mo e some

int erfe enc mine als in ad ition t o some of the matrix of a sample Ashing or chemical dig es ion

using formic acid or alkal is sometimes efe tive t o incine at e or dis olve int erfe enc mine als in the

matrix As desc ibed in ISO 2 2 2- 2, if the q antitative analy sis is t o det ermine amphibole v rieties

only, suc es ive r fluxing in acid and alkal can efe tively r mo e int erfe enc mine als, inclu ing

some si icat es, lea ing any amphib le mine als unalt er d An ex mple showing these efe t is shown

in An ex D

12 Quantitati ve anal ysis by X RD employing substrate standard mas absorption

c orrection

12.1 General

The difraction int ensity of a c y stal ne subs anc can be measur d using eithe the peak height or

the peak ar a ( int egral int ensity) Sometimes the peak height of difraction peaks from asbest os v ry

depending on the sour e of the asbest os, but the v riation ofthe int egral int ensities is smal F or this

analytical method, comme cial y-a aia le s an ard asbest os samples ar suita le for pr p ration of

calbration filt ers It is also important t o r cord the identities of the r fe enc s an ards used in the

analy sis be ause the weight of asbest os on the sample f ilt er is o tained b comp ring the difraction

int ensity o tained from the sample f ilt er with that o tained from the f ilt er pr p r d from the p rticular

asbest os s andard

12.2 Preparation of wor king cur ve

F or samples pr sumed t o contain asbest os mas fractions highe than a pro imat ely 1 %, pr p r the

wor king curve in ac ordanc with wor king curve I F or samples pr sumed to contain asbest os mas

fractions lowe than a pro imat ely 1 %, pr p r the wor king curve in ac ordanc with wor king curve I

Working curves shal ha e a cor elation coefficient of at leas 0, 99

NOTE 1 Stan ard asb stos samples are availa le from several org nizations inclu ing the folowing: JAWE

[Explanation of JAWE stan ard substances (in Japanese), 1 86; Tokyo, Japan ], NIST (Off ice of Stan ard R eference

Materials, Gaither burg, MD 2 8 9, USA), HSE (T le B , Davies LST, Ad ison J (1 96) Asb stos reference

stan ards ― Made availa le for analy sts An Oc u Hy g 40, 71 –714) UIC reference stan ards are also

availa le from several commer ial sour es

NOTE 2 Substrate stan ard metal plates such as zinc, aluminium, etc are commer ial y availa le

12.2.1 Pr eparatio of wor king cur ve I

Working curve method I wi be used t o analy se samples that ar es imat ed ac ording t o 9.2 c) t o

contain r latively high mas fractions of asbest os (> % ) Pr p r working curve I as folows

a) Weigh blank filt ers an measur the difraction int ensities from subs rat e s an ard metals on

w hich the blan f ilt ersar mount ed for pr p ration of the working curve

b) Weigh ac urat ely (t o the near s 0,0 0 0 g) 0,1 mg, 0,5 mg, 1,0 mg, 3,0 mg an 5,0 mg (hese ar

r fe enc v lues)of the asbest os r fe enc s an ard mat erial an put them in f ive sep rat e conical

flasks A dd 2 μl, 1 0 μl, 2 0 μl, 6 0 μl an 1,0 ml of 2 % formic acid and 40 μl, 2 0μl, 400 μl, 1ml

an 2 ml of dis i led wat er or iso ro y l alcohol t o these conical flasks using mic o-pipett es an

tr at them in an ultrasonic cleane for at leas 1 min

c) Plac each flask into the wate bath at a tempe atur of 3 °C for 1 min, pe iodical y shaking

the flask

d) Fi t er each of the suspensions ont o a 2 mm diamet er PTFE-co t ed glas f ibr filt er using v cu m

f iltration eq ipment Dry the f ilt ers an weigh t o the near s 0,0 0 0 g Use these filt ers as the

s an ard samples t o de ive working curve I

e) Mount each s andard f ilt er sample in the X-ra difract omet er an measur the difraction int ensities

of the metal ic subs rat e s an ard plat e an the r lev nt asbest os peaks Plot the working curve in

ac ordanc with the calculation of the subs rat e s an ard mas a sorption cor e tion desc ibed in

Annex B F or the subs rat e plat e, metals such as zinc or aluminium ma be used

12.2.2 Pr eparatio of wor king cur ve I

Working curve method I wi l be used t o analy se samples that ar es imat ed ac ording t o 9.2 c) t o

contain r latively low mas fractions ofasbest os (> % ) Pr par working curveIas folow s

a) Weigh blank filt ers an measur the difraction int ensities from subs rat e s an ard metals on

w hich the blan f ilt ersar mount ed for pr p ration of the working curve

b) Weigh a ccurately a ppro imately 1 mg ofthe asbestos s an ard sample an pla ce it in a 5 0 ml beake

with 1 0 ml iso ro yl alcohol Plac the beake in an ultrasonic b th for at leas 1 min to dispe se the

asbestos Trans e the asbestos suspension to a 1 00 ml v lumetric flask an make up to a v lume

of 1 0 0 ml b ad ition of iso ro yl alcohol The conc ntration of this suspension cor esp n s to

0,0 mg of asbestos pe ml If desir d, a suspension with the same conc ntration of asbestos can be

pr p r d b dispe sing 5 mg of asbestos in iso ro yl alcohol in a 5 0 ml v lumetric flask

c) Using a pipett e, take alq ot of 1 ml, 3 ml, 5 ml, 1 ml, 3 ml, 5 ml an 1 0 ml of the original

suspension and put each int o a conical flask

When taking each al q ot, shake the v lumetric flask containing the original suspension vig orously

an immediat ely with raw the alq ot using a pipett e

If the original suspension is lef t o s an for an ext en ed pe iod, the asbest os ma floc ulat e It

is very diff icult t o r -dispe se the flocs of asbest os an it is the efor ne es ary t o pr p r a new

suspension

d) Ad 1 μl, 2 μl, 6 μl, 1 0 μl and 2 0 μl of formic acid t o each alq ot of suspension, r spe tively,

an tr at in the ultrasonic b th for at leas 1 min

e) Plac each flask into the wate bath at a tempe atur of 3 °C for 1 min, pe iodical y shaking

the flask

f) Fi t er each of the suspensions ont o a 2 mm diamet er PTFE-co t ed glas f ibr f ilt er using v cu m

f iltration eq ipment Dry the filt ers an weigh t o the near s 0,0 0 0 g Use these f ilt ers as the

s an ard samples t o de ive working curve I

If the volume of suspension t o be filt er d is les than 1 ml, ad iso ro y l alcohol t o inc ease the

v lume t o at leas 1 ml This is t o ensur that a u iform dep sit is o tained on the filt er

g) Mount each s andard filt er sample in the X-ra difract omet er an measur the difraction int ensities

of the metal ic subs rat e s an ard plat e an the r lev ant asbest os peaks Plot the wor king curve in

ac ordanc with the calculation of the subs rat e s an ard mas a sorption cor e tion desc ibed in

Annex B F or the subs rat e plat e, metals such as zinc or aluminium ma be used

12.3 Proc edure for quantitati ve anal ysis

Car y out the q antitative analy sis as folow s

a) Mount the r sid al sample or sub-r sid al sample as pr p r d in 1 3 an 1 4 on the sample s an

in the g oniomet er of theX-ra dif ract omet er

b) Measur the difraction int ensities of the metal (zinc, aluminium, et c ) from the subs rat e

s an ard metal plat e an asbest os in the filt er sample u de the same con itions as those used

for the pr p ration of the working curve Ap ly the mas a sorption cor e tion t o the difraction

int ensities ac ording t o thesubs rat e s andard mas a sorption cor e tion proc d r desc ibed in

Annex B

c) Calculat e the mas of asbest os from the working curve pr p r d in 1 2 and the asbest os mas

fraction (% )

d) R epeat the proc d r s in a) t o c) on at leas thr e r sid al or sub-r sid al analytical samples an

r port he a e ag e v lue as the asbest os mas fraction ( % ) for the bulk mat erial

12.4 Calculation of asbestos mas fraction

Calculat e the asbest os mas fraction (% ) in the commin t ed sample ac ording t o 1 4.1or 1 4.2

12.4.1 Calculatio of asbestos mas fractio fr om a resid al sample

Calculat e the asbest os mas fraction in each r sid al sample using F ormula (4 ) C lculat e the a e ag e

asbest os mas fraction for at leas thr e r sid al samples using F ormula (5)

When the proc d r in 1 2 is used t o pr par the r sid al sample from a commin t ed sample that

contains an org nic comp nent, cor e t the calculat ed mas fraction b the weight los ratio, r

2and w

3);

is theweight of the commin t ed sample (mg);

R is theweight los ratio In the case of no weight los :r = 1;

w is theasbest os mas fraction in the original sample ( % )

12.4.2 Calculatio of the asbestos mas fractio from a su -r esid al sample

Calculat e the asbest os mas fraction from one sub-r sid al sample using F ormula (6) C lculat e the

asbest os mas fraction for thr e sub-r sid al samples using F ormula (5)

In the case of the sub-r sid al sample pr p r d b r d cing the mas of a r sid al sample un e the

heating conditions as in icat ed in 1 2, it hal be cor e t ed b the weight los ratio, r:

is theweight of the sub-r sid al sample (mg);

r is theweight los ratio In the case of no weight los :r = 1

12.5 Lower l mits of detection and quantitati ve determination for the wor king curve

Make 1 r plcat e measur ment of the int egral difraction int ensity of asbest os using the minimum

amou t of s an ard sample, 0,0 mg filt er(2 cm

2

) t o 0,1 mg filt er(2 cm

2

), pr p r d at the time of

pr paration of the working curve C lculat e the s an ard deviation of the int egral difraction int ensity

Calculat e the LOD of the working curve from the gradient of the working curve using F ormula (7)

Calculat e the LOQ of the working curve from the gradient of the working curve using F ormula ( 8)