QUN L CHT LNG PHNG TH NGHIM (QUALITY MANAGEMENT IN THE LABORATORY)

CHNG 1

TIU CHUN CHT LNG KHI NIM CHT LNG CHI PH CHT LNG (Quality Standards, Quality Concepts & Quality Costs)

Chng ny s trnh by: Tiu chun h thng cht lng cn p dng; Cc khi nim v cht lng, m bo cht lng, kim sot cht lng v ci tin cht lng; Gii thch cc chi ph cht lng.1.1. TIU CHUN CHT LNG Cng nhn phng th nghim Vit Nam v hu ht cc quc gia trn ton th gii v khu vc u da vo tiu chun ISO/IEC Guide 25:1990; Chu u da vo tiu chun EN 45001. Vo nm 2000, tiu chun ISO/IEC 17025 s thay th s thay th cho hai tiu chun nu trn. Cc t chc cng nhn Accreditation bodies nh Vn phng cng nhn cht lng ca Vit Nam VILAS s dng tiu chun ISO/IEC Guide 25:1990 lm1

chun mc cng nhn thng qua tiu chun TCVN 5958:1995 hoc mt s t chc khc nh NATA ca c, UKAS ca Anh, SINGLAS ca Singapore da vo ISO/IEC Guide 25:1990 v bin son li yu cu chung cho vic cng nhn phng th nghim ca tng bc. Ngun gc pht trin ca ISO/IEC Guide 25 Yu cu chung v nng lc ca phng th nghim v hiu chun. 1947 c (NATA) 1966 Anh (BCS) p dng vo lnh vc hiu chun Calibration. 1972 Tn Ty Lan. 1973 an mch, Thy in 1975 ILAC c thnh lp Internationl Laboratory Accreditation Conference 1976 Hoa K (NVLAP) 1978 Hoa K (A2LA) Nam Dng 1979 Php 1980 Anh (NATLAS) p dng vo lnh vc th nghim Testing Canada, Mexico 1982 - ISO/IEC Guide 25:1982 1990 - ISO/IEC Guide 25:1990 13.9.1996 ti Amsterdams Hi ngh ln th 14 ca ILAC chnh thc i tn ILAC t Conference thnh Cooperration Vi 44 thnh vin sng lp, trong c Vit Nam Internationl Laboratory Accreditation Cooperration Vit Nam p dng cng nhn phng th nghim t nm 1990 thng qua Php lnh cht lng hng ha ngy 27.12.1990. 1978 ISO Guide 25:1990

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Cc phng th nghim p ng yu cu ca ISO/IEC Guide 25:1990 (TCVN 5958:1995) ph hp vi cc hot ng hiu chun v th nghim cc yu cu c lin quan ca b tiu chun ISO 9000 (TCVN ISO 9000) bao gm cc yu cu ca m hnh m t trong ISO 9000 (TCVN ISO 9002). 1.2. KHI NIM V CHT LNG a) Cht lng l g? Crosby: cht lng l ph hp vi nhng yu cu qui nh. Deming: cht lng tt khng nht thit l cht lng cao Juran: cht lng l ph hp vi mc ch s dng. Ngoi cc nh ngha trn khi nim cht lng cn c xem l khng khuyt tt, l hon ho, l khng gy nhim, l mc tuyt vi, l s tha mn khch hng, l em li s thch th cho khch hng, l khng bao gi phi chu xin li khch hng v nhng thiu st (v khng bao gi c thiu st), l ln u lm ng nhng iu qui nh, cht lng l khng t tin, cht lng l khng cu ton. Cn ISO 8402:1994 (TCVN 5814:1994) th nh ngha cht lng nh sau: Cht lng thc th (i tng) to cho thc th kh nng tho mn nhng nhu cu nu ra hoc tim n. Cht lng cng c th c biu th bng mt cng thc n gin nh sau: Q = P/E Trong : P: s thc hin hoc kt qu. E: mong i ca khch hng. Khi Q = 1, th nhng mong i ca khch hng ph hp v ton b s tha mn ca khch hng t c. y l tnh trng l tng. Khi nim cht lng theo ISO 9000 c ngha l p ng nhng yu cu ca khch hng. 1.3. CHT LNG T C BNG Xc nh nhng yu cu chnh xc ca khch hng.3

m bo lun sn c tt c cc ngun lc, phng tin v k nng c yu cu p ng nhng yu cu ca khch hng. Vic lp k hoch, xy dng vn bn v thc hin h thng qun l cht lng m bo nhng mc tiu cht lng ca t chc p ng mt cch thch hp. m bo nhn vin c cung ng c y trnh , c o to, c hng dn cng vic, c gim st, c lnh o, say sa lm vic c y ngun lc c th hon thnh nhim v. m bo tt c cc hot ng c lin quan ti qu trnh cng vic c thc hin ng. m bo khi lm sai iu g th bin php khc phc c hiu qu c thc hin ngn nga ti din. Thc hin thng xuyn vic xem xt v nh gi v h thng cht lng v

qu trnh cng vic. V trn tt c: TT C CAM KT CA CC CP LNH O TRONG T CHC 1.4. M BO CHT LNG a) nh ngha ISO 8402: 1994: m bo cht lng l ton b hot ng c k hoch v c h thng c tin hnh trong h thng cht lng v c chng minh l mc cn thit to s tin tng tha ng rng thc th (i tng) s tha mn y cc yu cu cht lng b) m bo cht lng bao hm: Nhng hot ng trc tip nh thit k, trin khai, mua hng, qu trnh, bao gi, lu kho, vn chuyn n khch hng. Nhng hot ng gin tip nh tip th, qung co, ti liu k thut (t ri),

tip tn, cng vic vn phng, k ton, lm ha n, dch v khch hng. Mi vic tc ng n mi quan h gia bn cung ng v khch hng.4

Mi vic gp phn vo (hoc lm gim) s hi lng ca khch hng. Mi ngi trong t chc t gim c, cc nhn vin thc hin, n tt c nhn vin lin quan. Tm li, m bo cht lng trong phng th nghim bao gm: T chc v c cu, trch nhim v quyn hn. Tuyn dng nhn vin, dy ngh, o to v pht trin. Lnh o, ng c lm vic, gim st. Cung cp thit b, phng tin v mi trng thch hp. Chn la, xy dng v ph duyt phng php. Mua thit b v dng c. Nhn v chuyn mu. nh gi v sot xt, nhng chng trnh khc phc. Cp giy chng nhn, lu gi h s. m bo cht lng bao hm mi hot ng v chc nng lin quan n cht lng v s tin cy ca dch v c cung cp. 1.5. KIM SOT CHT LNG a) nh ngha: Juran: Kim sot cht lng l qu trnh thng xuyn m chng ta kim tra vic thc hin cht lng trn thc t, sao cho n vi chun mc v tc ng vo s chnh lch. Vi nh ngha khc: Kim sot cht lng l vic kim sot v theo di cc thnh phn ca h thng m bo cht lng. ISO 8402:1994: Kim sot cht lng l cc hot ng v k thut c tnh tc nghip, c s dng nhm p ng cc yu cu cht lng. Kim sot cht lng bao hm nhng hot ng v k thut c tnh tc nghip nhm theo di qu trnh v loi b nhng nguyn nhn khng thch hp mang li hiu qu kinh t.5

b) Qui trnh kim sot cht lng: Theo di vic tin hnh ng h thng m bo cht lng. Sm cung cp nhng ch ban u t h thng m bo cht lng. Pht hin nhng thiu st hoc sai li trong thit b, phng tin v th tc. m bo ton b h thng cht lng ang tin hnh nh d nh. Kim sot cht lng bao hm mi hot ng v chc nng c thc hin m bo rng h thng cht lng ang tin hnh nh d nh. 1.6. CI TIN CHT LNG Thit lp v duy tr mt h thng cht lng c cng nhn (nh h thng cht lng PTN) hoc c chng nhn (nh h thng cht lng theo ISO 9000) l mt bc t c cht lng sn phm no v do vy mang li tha mn cho khch hng. cng l bc thay i ln (trong qu trnh, quy trnh v do vy em li kt qu), vic lng ph v tht bi (nh hu qu gy ra) Nhng y cng l bc u tin. gi vic ci tin cht lng v gim chi ph lng ph, thay i v tht bi, ta cn tip tc ci tin mi vic ta lm. Hai iu tt gia tng trong vic ci tin cht lng l thc y nhn vin sau sa lm vic v tha mn nhng yu cu khch hng nhiu hn nhu cu ca h (hoc iu h mun). Tiu chun h thng cht lng nh ISO/IEC Guide 25 v b tiu chun ISO 9000 cung cp cho chng ta nhiu cng c t c s ci tin tip tc, bao gm: -

o to (tt c nhn vin). nh gi ni b. Chng trnh hnh ng khc phc. kin phn nh. Xem xt ca lnh o. o lng chi ph tht bi v pht hin ni no vic ci tin l cn thit (k thut thng k).

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B sung vo cc kha cnh ny ca tiu chun h thng cht lng, chng ta c th s dng nhng phng tin khc ci tin nh: Gim st vic hi lng ca khch hng (cho hu ht l khng khiu ni, nhng mt vi ni c th khc).

Thng tin thng m vi khch hng ( m bo h bit r rng nhng g bn cn v ti sao v bt c vn bn c).

im qui chiu l da vo iu tt nht trn th gii hay trong x s bn. Tiu im qun l (nhn v qu trnh ng, hn l tiu im ch cui cng)

Kiu qun l, c bit l: + Gip nhng ngi tham d / hoc lin quan n khu vc thch hp nh gii quyt vn , ra quyt nh, ci tin. + Tha nhn hoc thch hp vi nhn vin nhiu hn (chn tht). C th tham kho thm TCVN ISO 9004.4 Hng dn ci tin cht

lng. 1.7. CHI PH L G? Sai li trong th nghim v o lng v lng ph trong qu trnh thng l dn n cht lng km, trnh lm hng ngun lc ca phng th nghim. Sai li trong th nghim v o lng lm hao tn tin bc, chi ph ny c th c nhn bit v o c. Nu sai li khng c pht hin trong phng th nghim nh c chuyn n khch hng th chi ph ton b cng ln. h thng cht lng t hiu qu, iu quan trng l chi ph cht lng c tip tc nhn bit, o c v theo di ban lnh o c th nh gi y h thng cht lng v xc nh c hi cho vic ci tin. a) Chi ph tht bi Ton b chi ph mang li trong qu trnh, hng ha hay dch v khng p ng cc yu cu qui nh.7

* Tht bi t bn trong: Nghin cu vn . Th li mu. Thc hin ti vic kim sot cht lng. Hiu chun li. Hao tn thi gian ca nhn vin ch cht. Sn phm khuyt tt c sn xut (kim tra cht lng PTN). Ni cch khc, chi ph sinh ra t bt k s khng ph hp no ca th nghim, thit b, kim sot cht lng, ly mu, qu trnh sn xut, vt liu sn phm, kim tra ni b, mua hng, an ton) * Tht bi t bn ngoi: Nghin cu khiu ni. Xem li bo co th nghim. Th li mu. Lm li sn phm. Mt khch. Chi ph kin tng / tranh chp. b) Chi ph nh gi Ton b chi ph mang li trong kim sot qu trnh v kt qu ca h thng cht lng l ph hp yu cu c qui nh. Qui trnh kim sot cht lng. Kim tra thit b. S dng chun chnh. Gim st. Kim tra cng vic vn phng.8

Ch yu, chi ph nh gi lin quan n h thng v cc th tc kim sot cht lng. c) Chi ph phng nga Ton b chi ph mc phi trong lp k hoch, thc hin v duy tr h thng cht lng: Lp k hoch h thng. Lp vn bn h thng. o to nhn vin. Chng trnh m bo thit b. Trin khai v chn la phng php. Xem xt h thng. Ch yu, chi ph phng nga lin quan n h thng m bo cht lng. Cch tnh nhng chi ph ny: tnh ton mt cch y chi ph tht bi, chi ph nh gi v chi ph phng nga, nhng nhn t cha ng trong mi nhu cu ny s c lit k y trong 3 loi chi ph, xc nh chi ph thc tn hao cho tr tin lng, thit b, mu mi, vt liu, vin thng, du lch, o to, i l bn ngoi, thu li tc, thi gian th nghim c th xy ra trong mi nhn t. Nhng iu ny cn x l trong thi gian thch hp nh 3, 6 hoc 12 thng. d) Cch sp xp chi ph cht lng Trong mt h thng khng k hoch ha: Nhn mnh im li khc phc hn l phng nga. Tng chi ph tht ca nhng tht bi l khng bit. Chi ph tht bi cao a n tng chi ph cht lng khng c tha nhn.

e) Chi ph cht lng lc quan9

Xc nh mc ca cht lng v nhu cu tin cy c v ri. Nhn mnh im phng nga. Xc nh quy trnh kim sot (nh gi) chi ph hiu qu nht. Gim chi ph khng thnh cng n mc thp nht.

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QUN L CHT LNG PHNG TH NGHIM (QUALITY MANAGEMENT IN THE LABORATORY)

CHNG 2

TRCH NHIM & NGUN NHN LC (Staff Resources & Responsibilities)

Chng ny s: Nu ln trch nhim ca cc nhn s phng th nghim; Ni dung v ngha ca m t cng vic; Nhng vn cn lp vn bn.

1.1. XC NH TRCH NHIM NHN VIN a) ISO/IEC Guide 25 yu cu nhng g? Cn b qun l thm quyn v ngun lc hon thnh nhim v C cu t chc m bo mi thnh vin PTN khng chu bt k sc p Trch nhim, thm quyn v mi quan h qua li gia qun l, thc tin v kim tra Nhn vin gim st phi y s lng v hiu r cc th tc v cc phng php th. T l phi thch hp Trch nhim ca qun l k thut

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Trch nhim ca qun l cht lng Sp xp (b tr) cp ph gii quyt khi cn (bng vn bn)

Ban lnh o cng b chnh sch cht lng bao gm mc tiu v cam kt

Ch r s t chc c cu nhn vin ca phng th nghim v quan h ca h i vi cc n v khc M t cng vic ca tt c nhn vin qun l v th nghim Ch r ngi c thm quyn nh gi ring ni b phi c o to v trnh , hon ton c lp vi hot ng b nh gi C y nhn vin c trnh , kin thc v kinh nghim Bi tp: Xem xt cc yu cu ca tiu chun ISO/IEC Guide 25: 1990 Anh ch th lin kt cc yu cu trn vi cc iu trong ISO/IEC Guide 25: 1990. b) C s t chc l cha? Hu ht t chc u c mt s t chc ch r c cu ca t chc v chc nng v tr c trong s . Nhng s nh th cho chng ta bit mi quan h ca nhng chc nng vi nhau song s ch cho chng ta mt phn hoc khng nu ln iu g c v mc ch v phm vi ca mi v tr chc nng. Vi mi v tr trong s t chc, cn ghi r v mc ch ca chc nng v quyn hn, trch nhim ca ngi gi v tr . c) V sao nh vy? Nhn vin cn c bit t chc yu cu h iu g.

Nhn vin cn bit vai tr v chc nng ca h trong t chc; h c trch nhim v quyn hn no, v nhng nh hng qua li gia cc chc nng.

Nhn vin quan tm hn t c mc tiu khi bit nhng mc tiu ny l g v khi c c hi th tham gia thc hin.12

2.2. NGHA CA M T CNG VIC a) i vi t chc * Xc nh nhim v v trch nhim: Ch r mi v tr thch hp trong c cu chung. Trnh mu thun v ln xn qua nhng trch nhim c lp li hai ln hoc mt trong hai khng c ch r. * Xem xt nng lc nhn vin: Lnh o khng th thc hin s nh gi cng bng nu mc tiu v chun mc khng c xc nh. Thiu m tc cng vic, s xem xt m t thnh ch quan v c nhn. M t cng vic tp trung ch vo cng vic ch khng mang tnh c nhn. * Xp loi cng vic: Nhng cng vic v cht lng cng vic c th ch c thit lp v so snh nu cng m t cng vic c xc nh r rng. * Xc nh yu cu i vi nhn vin: Ch c th qui nh yu cu i vi nhn vin nu t t cng vic. Ch r iu ny trong tuyn dng v qung co. * o to v xy dng: Khi m t cng vic ca tng c nhn c xc nh bao gm nhim v h c th lm iu c th tr thnh d xc nh nhu cu o to v hun luyn chnh xc hn. * S tha mn cng vic, s hng sai lm vic v cam kt c nng ln: M t cng vic c xy dng r rng nht thit dn n tha mn cng vic hn, gim thiu s cng thng v m h. Nh , nhn vin hi lng hn v sau sa lm vic cng nh cam kt quan tm hn n cht lng cng vic. b) i vi nhn vin * Gim cng thng v m h:13

Nhn vin nhn thc y v nhng g mong i h m t cng vic v h cng bit c lnh o nh gi h nh th no. * C hi tham gia: Nu m t cng vic c chun b tt, ngi cng s c c hi tham d vo cc chng trnh tp hun v do h p ng c cc yu cu ra m mc tiu v chun mc ra. 2.4. CHUN B S M T CNG VIC a) Kiu Ni dung Hnh thc Lnh o nn la chn v quyt nh. b) D tho ban u Nn giao cho ngi c giao vic chun b (c th hon ton khc so so vi suy ngh ca ngi qun l). iu ny cung cp c hi bit c cng vic ngi c giao vic thc hin. c) Tho lun v xem xt d tho Ngi qun l tho lun d tho vi ngi chun b v gii quyt cc im khc bit v trch nhim hoc nhim v c giao ph. C hai cng thit lp nhng phn ch yu ca cng vic v tham gia tho lun v thng nht mc tiu. d) Lun chuyn kin Nhng ng nghip, nhng ngi ngang cp v thm ch cp di c th c mi xem xt d tho. iu ny cho h c hi xem xt m t cng vic ring ca h trong mi lin quan vi d ho. e) Chun b bn cui cng n hnh v phn phi nh m t cng vic. 2.5. NI DUNG CA M T CNG VIC a) Tiu cng vic Tn cng vic phi c m t chnh xc sao cho bn trong phng th nghim v c bn ngoi hiu y ni dung. b) Chu trch nhim vi ai?14

Ai thay mt cho cp trn? c) Ai c gim st? Ghi li mt thuc cp di. d) Cng b mc ch chung ca cng vic Xc nh mc tiu chnh ngn gn. e) Cng b mc ch tng qut ca cng vic Cng vic ch yu l mt phn cng vic c nhn nhm gp phn t c mc tiu chnh ca cng vic. Cng vic ch yu hy vit tht n gin. Phn bit gia trch nhim trc tip (iu g anh ta thc hin) v trch nhim qun l (iu g anh ta m bo rng nhng ngi khc thc hin). ng b st chc nng ph nhng quan trng. f) Thng tin no cn kim sot? Cng b cch thc v khi no c nhn s bo co v phm vi hot ng v trch nhim ca mnh. g) Cng b gii hn ca quyn lc n gin thng, cng b iu g khng c lm. h) M t cng vic cng c th bao gm Chun mc ca cng vic c yu cu (nh trnh by, chnh xc, thi gian thc hin). iu kin lm vic (gi, lng) 2.6. CNG B TRCH NHIM a) T chc ln Trong nhng phng th nghim ln vi c cu t chc n nh, vic m t cng vic thng l nhng ti liu khng mang tnh c nhn. Thng l: Lin quan chc nng hn l lin quan n c nhn. c trnh by tng qut.15

t khi sa i. Trong nhng phng th nghim nh th, cng b nhim v ring l c ch. Thng l: Mi c nhn trong phm vi cng vic ch yu lp danh sch nhng mc tiu ngn hn c th cn t c. Tr thnh c s cho mc tiu thc hin v nh gi thc hin. Cn c bo mt, ch c c nhn v ngi qun l ca h bit. b) T chc nh Trong nhng phng th nghim nh, c cu nhn vin cn phi thch nghi hn, linh ng hn. Mt ngi c th m nhim nhiu chc nng.

Khi thay i nhn vin, cng vic hoc c thm nhng chc nng quan trng, mt vi chc nng c th c chuyn t c nhn ny sang c nhn khc.

Nhn vin m nhim nhiu hn mt chc nng thng c kinh nghim. Trong nhng phng th nghim nh th, cng b nhim v ring l c ch. Thng l: Gi ra ng thi tt c nhim v mi c nhn mong i thc hin di nhiu chc nng.

D dng chuyn chc nng t c nhn ny sang c nhn khc khi nhn thy nhn vin b qu ti.

c) Bt k t chc no Trong phn ln bn m t cng vic, cng vic ch yu cn thit phi c vit trong iu khong chung nu m t cng vic l c gi tr tng i. Thng khng nn a qu nhiu mc tiu, ngn hn m nhn vin phi t c. Cng b nhim v ring l trong nu nhim v then cht trong iu kin thc t t c mc tiu ngn hn sao cho hp l.

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Trch nhim ca cng vic chnh c th thng c din t bng s lng hay bng thi hn cui cng hoc bng nhng mc tiu c th cho thi k ti.

Nhng ch th th xc nh nhng mc tiu ngn hn t c v cung cp c s cho vic nh gi v t nh gi. 2.7 XEM XT NH K Khi thay i nhn vin v chc v, ni dung ca m t cng vic v cng b nhim v phi c thay i theo. Thm ch vi s thay i nh khng quan trng nhng din ra nhiu cng yu cu thay i m t cng vic v cng b nhim v. M t cng vic nn c xem xt t nht hng nm m bo rng cng vic tip tc m t ng trch nhim nhn vin. Cng b nhim v thng c bin son hng nm cho ti thi k 12 thng. Thng vic ny c lm kt hp vi nh gi nhn vin. M t cng vic v cng b nhim v cng phi c xem xt bt c khi no thay i quan trng trong nhn vin hoc trch nhim. 2.8. XY DNG NGUN NHN LC a) ISO/IEC Guide 25 yu cu Phng th nghim phi lu gi h s thch hp v trnh , o to v kinh nghim ca nhn vin. b) PTN phi lm g? Mc ch ca yu cu ny l lnh o phng th nghim nn: Xc nh trnh , chuyn mn, kin thc v k nng c yu cu cho mi nhn vin trong phng th nghim. Lp h s v theo di trnh , o to v kinh nghim ca mi ngi trong phng th nghim. i chiu kh nng c nhn vi chc v c giao trn c s trnh , o to, kinh nghim, kin thc v k nng.

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p dng yu cu ny, qun l phng th nghim s nh gi nhu cu c th ca phng th nghim. Nguyn tc chung l: Trnh , o to, kinh nghim nn c xc nh cho mi cp qun l, gim st hoc chuyn gia k nng trong phng th nghim. H s trnh , o to v kinh nghim ca mi thnh vin trong nhn vin phng th nghim nn c lu gi. 2.9. H S NHN VIN Ti thi im tuyn dng, mi nhn vin mi s cung cp thng tin v trnh v trc tin v kinh nghim cng tc cho lnh o PTN. Qua mt thi gian, c nhn s c c nhn yu cu o to thm, v s c kinh nghim cng tc v trnh kh hn. Do h s c nhn v kt qu o to phi c lu gi v nn bao gm vi hoc tt c nhng chi tit sau: a) Trnh Chi tit nhng kha hc qua, cc t chc / hi m h tham gia qua. b) Kinh nghim cng tc Tm li kinh nghim cng tc trc y, bao gm v tr gi, hot ng thc hin v thi gian tham gia. c) o to Chi tit ca tt c cc lp o to m c nhn tham d nn c lu gi, h s ny nn bao gm chi tit v lnh vc o to, xc nh ngi ging dy hoc t chc o to, thi gian tham d v bt k giy chng nhn c cp. H s o to ny nn c cu to theo nhng biu mu c sn ca nhng lp o to bn ngoi, ni b v lp hun luyn ngh nghip cho cng vic v chc nng c th. d) Hi ngh v chuyn (seminar) H s v c nhn tham d trong hi ngh v chuyn , c bit ni c nhn trnh by hay thuyt trnh nn c lu gi vo h s.

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e) Hi vin ca Hip hi v y ban H s v hi vin ca vin chuyn mn v hip hi cng nn c lu gi. f) Quan tm c bit C nhng phng th nghim quan tm n cc thng tin c bit v nhn vin, thng hot ng khng chnh thc c khi c th c ch trong ni lm vic, chng hn:

Hi vin hot ng ca tp on dch v t nguyn c th l du hiu ca nng lc lnh o.

nh gi nh mt ti t thch hp vi sn khu hoc tranh lun x hi pht huy k nng ni.

Hiu bit ngn ng khc c th gip khi chuyn dch ti liu nc ngoi. Kin thc v s tay k nng pht trin bi nhng s thch c th c dp x dng trong phng th nghim khi nhim v c bit cn n. Cc loi h s ch c th c gi ni c o c v tnh ng i trong phng th nghim. 2.10. TM LI ng qu lo l h thng cht lng c cu to v lp vn bn nh th no cho tt. S thnh cng v hiu lc ca bt k phng th nghim ty thuc vo vic PTN c y nhn vin c k nng, gim st thch hp v qun l hiu qu.

Nhn vin gim st phi y s lng v nng lc c quyn kim sot k thut thng qua cc hot ng ca phng th nghim.

Nhn vin no c cp php thao tc m khng chu mt sc p no.

Tt c cc nhn vin th nghim phi c o to thch hp, v tip tc o to c th ch r chc nng v cng vic trong kh nng h. Phm vi ca mi chc nng trong phng th nghim, v gii hn quyn lc ca c nhn nm gi nn c vn bn ha trong m t cng vic v giao tip trong phng th nghim.

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Bt c ni u c th, cng vic chnh bao gm trong m t cng vic nn c mc tiu r rng trong cng b nhim v.

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QUN L CHT LNG PHNG TH NGHIM (QUALITY MANAGEMENT IN THE LABORATORY)

CHNG 3

QUN L O TO (Management of Staff Training)

Chng ny s: Trnh by o to l g? V sao v khi no cn o to? o to nhng g v o to u? Lm th no o to t hiu qu?.3.1. GII THIU o to l mt phng php nhm nng cao kh nng thc hin ca c nhn thng qua vic qun l c h thng vic hc tp cch c x mi, kin thc mi p ng mc tiu ca c nhn v t chc. Nhng pht trin cng nhm ci thin cch c x, k nng v kin thc ca nhn vin, song khng cp bch nh o to. Pht trin mt thnh vin trong t chc l cho nhu cu tng lai. 3.2. TI SAO PHI O TO? Mt phng th nghim lin quan n vic o to v nhiu l do. Mt nhn vin mi ln u tin m bo mt cng vic cn phi c o to hon thnh nhin v ca mnh, bt k nhn vin t chc no. Ngay c nhn vin c kinh

21

nghim cng cn phi thng hiu cc hng dn ca t chc, cch b tr phng th nghim cng nh tnh thng nht v h thng v chnh sch ca t chc . Hn na, hot ng ca phng th nghim khng phi l mt qu trnh tnh. Khch hng mi, sn phm mi, thit b mi u c nh hng n cng vic v lm thay i bn cht ca cng vic. Thm ch nu khng c nhng s thay i su sc nh vy, th phng php cng lun lun pht trin v cc nhn vin phi c nng cao nghip v p ng nhim v mi, trch nhim mi. C nhn vin c ln nhn vin mi u phi c o to. Ba mi nm trc, o to s dng cho 10 n 15 nm. Hai mi nm trc, o to s dng cho 8 n 10 nm. Mi nm tr li y, o to ch cn s dng cho 5 n 8 nm. Nm nm gn y, o to ch cn s dng cho 2 n 3 nm. Ngy nay, o to ch s dng 1 n 2 nm. iu ny ni ln rng tin b khoa hc ngy cng pht trin nhu cu cu o to cng lun thay i theo. 3.3. KHI NO CN O TO? o to l mt qu trnh lu di, mt s u t v nhn lc v cng l iu cn thit khi cc mc tiu, k hoch ca t chc c thc hin trong tng lai. Khi c k hoch m rng hoc hp ng lin quan n cc hot ng mi (thit b khc, t chc khc, v tr khc) nhn vin phi c o to trc khi cc s thay i din ra. Tng t, khng phi lc no cng d dng d on c nhu cu o to v c s thiu ht v nhn s. Do , nu chng ta d on c cc yu cu thay th v o to kip thi nhn vin k thut v nhn vin qun l th c th gim bt s ht hng v nhn s trc khi vn ny xy ra. 3.4. O TO U? Khi xem o to l cn thit, vic quyt nh o to ni b hay bn ngoi cn phi c xem xt k. C hai hnh thc o to trn u c nhng thun li v

22

hn ch ca n, do phi cn nhc sao cho ph hp vi c nhn, t chc v mc tiu o to. a) o to ni b Thun li: - Hc vin hc ti ch. - Hng dn c th i vi cng vic v phng tin hin c. - Vic o to c theo di d dng. - Vic o to linh ng v d sa i. Nhng: - Cn c k hoch v cam kt ca nhn vin. - Tn nhn vin v thit b hin c. - nh hnng n ton b cng vic. - Cc thi quen xu d c b qua. b) o to bn ngoi Thun li: - Tt cho vic dy kin thc c bn v k thut c bit. - Khng nh hng n nhn vin v phng tin hin c. - c cung cp ngun o to. - Mi trng khc nhau. Nhng: - Tn km c v thi gian v tin bc. - Khng c th i vi hot ng ca nhn vin. - Ni dung kha hc khng linh hot 3.5. O TO CI G? Xc nh nhu cu o to: Trc khi bt u chng trnh o to, chng ta cn bit nhn vin o to nhng g. ng bao gi gi nh mi vic. Chng ta cn bit nhn vin bit g v k nng no h c v lnh vc no h cn o to. C th nhn bit s thiu ht v k nng v kin thc ca nhn vin thng qua s quan st, t cu hi, chng trnh kim tra cht lng thm ch c thi c. Cc qu trnh ny c thc hin di danh ngha nh gi k nng (Skills Audit).23

p dng k thut phn tch nhu cu o to l mt cch xc nh xem nhu cu o to hin c, liu i hi o to g p ng nhu cu . C nhiu k thut phn tch nhu cu o to. Cch ph bin nht l: 1. Bn cu hi (Questionnaires) Cc bn ny c nhiu hnh thc: a) Lnh o chun b mt danh sch cc lnh vc cn o to, v nhn vin s nh du cc yu cu theo th t u tin i vi h. b) T bng cng b nhim v nhn vin lp danh sch cho tng nhim v c giao ca mnh v trong mi nhim v c yu t chnh no cn thc hin nhim v. i vi tng yu t ny, h ch th ghi ch mc o to m h cn (v d o to nhiu, o to t) c) Gim st vin lp danh sch tt c cc k nng v kin thc cn thit cho tng nhim v, nh gi nhn lc tng nhn vin tng ng vi tng nhim v. thc hin tt (b) v (c) phi c s lin kt gia nhn vin v gim st vin ca h, nhm to nn mt hnh nh r nt hn v nhu cu o to, v s tip cn tp th tt hn. 2. Phng vn tng ngi Hnh thc ny mt nhiu thi gian hn l phng php lp bng cu hi, nhng c th thu c nhiu thng tin hn. Cc cuc hp nh gi nhn vin v thi im tt xem xt nhu cu o to (hoc nhu cu pht trin). t c s phn tch chnh xc nht nhu cu o to, cn p dng nhiu phng php phn tch nhu cu o to. 3.6. O TO NH TH NO? (Tham kho hnh 1) a) Lp k hoch o to tn km v cn u t ln v thi gian v tin bc. Do , phi lp k hoch cn thn thu c hiu qu mong mun. Thng nht v nhu cu o to

24

S tham gia vo chng trnh o to s khng c kt qu tr khi mi ngi u thng nht v nhu cu o to ca mnh. ra mc tiu Nhng mc tiu ny s m t mc hot ng m hc vin t c cui kha hc. iu cn thit l phi xc nh mc tiu r rng, thc t, tt nht l nn t di dng cc hot ng c th o c. Quyt nh ni dung o to Ni dung o to phi c xc nh p ng nhu cu t ra. N phi ph hp vi trnh ca hc vin v phi r rng v kin thc hoc k nng. Ni dung o to phi bao gm nhng im sau: (1) Kin thc: bao gm ba loi: - Thng tin c bn (nguyn vt liu, trang, thit b, phng php, phng thc m cng vic tin trin, cch ghi h s v bo co, kim sot cht lng, thi gian cho php) - Cch nhn bit sai st trong qu trnh, cch khc phc v phng nga. - Ti sao phi thc hin cc php th v kt qu c s dng ra sao. (2) K nng: Cn lm g, lm nh th no, h qu ra sao (tng giai on nh cng nh tng giai on ln). (3) Thi : bao gm: - An ton, v sinh. - Cht lng (tm quan trng nu thc hin ng, hu qu nu thc hin sai). Quyt nh cc phng php o to hu hiu nht Chn phng php sao cho ph hp nht vi iu kin hot ng do mc tiu ra v phng php phi to iu kin cho hc vin thc hin tt cng vic ca mnh trong thc t. Cui cng, chn cc phng thc sao cho hc vin c th thu thp c nhiu kt qu trong mt khong thi gian nht nh.

25

Nu thch hp, tt c chng trnh o to nn kt hp c ba phng cch hc: nhn, nghe, thc hnh (v d: ch cho hc vin thy, ni cho hc vin nghe, yu cu hc vin thc hnh). D nhin, vic la chn phng php o to thch hp phi da trn cc tiu chun hnh chnh nh ngn sch, ngun lc c sn v tnh thc t. o to ngi hng dn Nhn vin c nng lc cao cha hn l ngi hng dn gii v chnh h cn phi c tr gip tr thnh ngi hng dn tt. Chi ph Chi ph cho chng trnh o to cn c tnh ton v so snh vi nhu cu ca t chc v li ch ca n. u tin ca t chc l g v c li ch g khi so snh vi ph tn b ra. Nu chi ph qu cao, cn xem xt li nhu cu o to v sa i li chng trnh (nu cn thit). b) Thc hin vic o to v lu h s Trong qu trnh o to, chng ta phi chun b cho hc vin. ng tic thi gian gii thch mc ch chng trnh o to v n s lm tng ng c hc tp v s tip thu ca hc vin d dng hn. Chng ta phi gii thch v hng dn ti liu hc tp cho hc vin mt cch t t. C th lm vic vi mt checklist nhng trnh khi thi gian biu qu cng ngt d gy tht vng v nhm chn. Hy dy tng bc quan trng v dng li mt cht nhn mnh cc im then cht. phn thc hnh, nn c ngi hng dn. Hy khuyn khch ng v chn chnh ngay cc sai phm (nu c th c). Hy hc vin gii thch cho chng ta bit h ang lm g. Hy kin nhn. Hy lm gim s lo lng ca h bng mt thi thn thin v gn gi. Hy lun c nhng sa i trong o to, tt nht l dng cc k nng c vo trong cc ng dng mi. Khuyn khch vic t cu hi v phn hi ca hc vin cc im quan trng. Hy biu dng cng vic v cc qu trnh tt v hy trnh s phn ng tiu cc t pha ngi hng dn.

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Cui cng, lp h s o to c s nh gi mc tip thu ca hc vin (tham kho hnh 2: v d v h s o to). nh gi khng nht thit phi c bi kim tra chnh thc m c th quan quan st v so snh cch thc hin vi mc tiu c v tiu chun v tc . Xc nh nhu cu H s Gii thch: - Cch thc - Thng tin - Thi

Phn hi: - C th - Tc th

Hng dn: - T t - Trong K bnh thng

nh gi u n c) nh gi

Thc hnh

o to v tn km, do hiu qu ca n phi c nh gi. Gi tr ca o to ch c th o c qua cc hot ng c ci tin. Khi nh gi cc chng trnh o to, nn hi cc cu hi sau y: Vic o to c c thc hin mt cch t chc (c lp k hoch vi mc tiu r rng p ng cc yu cu t ra hay khng? K hoch o to c c thc hin khng? Vic o to c p ng cc mc tiu ra hay khng? Vic o to c p ng cc mong i ca hc vin hay khng?

27

Khng d nh gi hiu qu ti chnh ca o to bi v rt kh tch vic o to ra khi cc yu t khc. Cc thng tin thu thp c qua qu trnh nh gi s cho chng ta thy r cc vn cn c thay i. Vic nh gi cng nhm xc nh cc yu km lm cho vic o to khng hiu qu hoc cc mc tiu chn c thch hp hay khng? 3.7. TM TT o to l mt yu t then cht trong cc trch nhim ca lnh o. t hiu qu cao, vic o to phi c ra v thc hin nghim tc. Vic thit lp chng trnh o to phi c tnh h thng v phi th hin c nhu cu ca t chc v ca hc vin. Nhu cu o to phi c xc nh, vi mc ch r rng, hp l v c th o c. Ni dung o to, phng php truyn t phi ph hp vi kh nng ca hc vin. Qu trnh hc tp phi c lp h s v nh gi v xem xt v tnh hiu qu ca chng trnh o to. Lun nh rng hc vin l cha kha ca s thnh cng trong o to. Chnh h, nhng ngi ham hc hi s tm thy cch h phi lm t kt qu tt, thm ch khi vic o to khng c hon ho v c hiu qu nh mong mun. Ngc li, nu h khng mun hc hoc khng ng vi ni dung, hoc phng php o to th chc chn khng thc hin c vic o to. Do , nhng ngi qun l v cc hng dn vin phi to cho hc vin mt mi trng hc tp tt v khch l cc nhu cu hc tp ca h.

28

HNH 1 CC BC CA MT CHNG TRNH O TO C H THPNG Chun b gio dc gm: - Kin thc/nhn bit sai st - K nng/h qu - Thi /s an ton

c lp mc tuu to Hc vin c nng lm g sau kha hc

Chia nh cng vic theo tng giai on hc tp

Chn phng php v cc phng tin tr gip cho o to

nh hoc cp nht u cn thit)

nh gi hiu qu o to Hc vin c th lm g i vi cc yu cu t ra?

- Chn hc vin - Tin hnh ging bi - Kim tra hc tp (quan st, t cu hi)

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(QUALITY MANAGEMENT IN THE LABORATORY)

CHNG 4

TIN NGHI & MI TRNG PHNG TH NGHIM (Laboratory Accommodation & Environment)

Chng ny s:

Gii thch nh ngha v phng th nghim theo ISO/IEC

Guide 25:1990.

Trnh by cc kha cnh v tin nghi & mi trng v qun

l lnh vc ny.4.0. PHNG TH NGHIM L G? ISO/IEC Guide 25:1982 nh ngha phng th nghim l ni o lng, th nghim, hiu chun, hoc xc nh cc ch tiu, s ph hp ca vt liu hoc sn phm. ISO/IEC Guide 25:1990 nh ngha phng th nghim l mt t chc th nghim v/ hoc hiu chun. Tin nghi c th nh ngha nh l phng tin m cc hot ng th nghim c tin hnh. Nn nh rng th nghim ch l mt chc nng ca phng th nghim, ngoi ra cn c cc chc nng khc nh chun b mu, thun ha mu, lu gi h s v bo co. Cn xem xt mc ca khoa hc v cng ngh m s dng30

H thng ny m bo vic o to lun gn vi cng vic

QUN L CHT LNG PHNG TH NGHIM

Xc nh cng vic - C cn o to

iu

th nghim trong phng th nghim tp hp cc d liu. Ngi ta cho rng vic tin nghi ca mt phng th nghim c th c rt nhiu dng. Rt nhiu trng hp v vic th nghim hoc o lng hay ngay c hiu chun phi c tin hnh hin trng bi v cc mu th khng th mang n phng th nghim c. Tin nghi ca phng th nghim tt nhin bao gm c mi trng, m cc iu kin ca n cn phi c xc nh, cc kt qu th nghim khng b nh hng. 4.1. TIN NGHI Tin nghi v mi trng ca mt phng th nghim khng th xem xt mt cch phin din, cn xem xt c nhng kha cnh ca phng tin khng tc ng trc tip n cc kt qu th nhim nh: Thit k Xy dng Khng gian Kho tng c Cc dch v An ton.

i vi cc phng th nghim trong giai on xem xt thit k mi (hoc sa sang li), c th tham kho cc hng dn v nhiu thng tin khc khng tiu chun AS2982 Laboratory Construction. Cc yu cu tng qut v tin nghi:-

Tin nghi ca phng th nghim phi to mi trng th nghim, tha mn cc iu kin ring bit ca cc phng php th, phi c ch nhn vin c th tin hnh cng vic mt cch hiu qu v phi c c s vt cht thch hp t cc thit b v cc h s.

-

Cc yu cu v tin nghi thay i rt nhiu ty thuc vo bn cht ca cc mu th nghim, phng php th v mc chnh xc i hi.

31

-

Cn lu m bo rng thit b th nghim v cc chun khng b tc ng bi n mn, nhit , dao ng, ngun in khng n nh, nh hng bi v t tng.

-

Cc mu th phi c bo v thch hp khng b h hng hoc nhim bn.

-

Cc khu vc khng tng thch phi c cch ly mt cch hiu qu. Cc my tnh cn phi t trong nhng iu kin thch hp, thng thng l phng c iu ha nhit (xem ISO 554:1976).

-

-

Vic tip cn, s dng tt c cc khu vc nh hng n kt qu th nghim v an ton thng tin cn phi c xc nh v kim sot.

4.2. MI TRNG Ty thuc vo cc yu cu ca vt liu cn th nghim hoc phng php s dng m m rng phm vi mi trng phng th nghim. Tt nhin tng cng ngh u c yu cu c th, nhng thng thng l cc yu t: nh sng: bao gm c t nhin v nhn to. Nhit mi trng v m lin quan. Thng gi (bao gm vic ht kh c), kim sot nhim bn. Bc x t trng. m thanh.

Mi phng th nghim u c mi trng lm vic v cng phi cn ch n s tin li v an ton cho nhn vin. Nhng thng s no cn phi xem xt thm?-

Gi v sinh phng c. Ting n. An ninh Khong cch An ton Cc tin nghi khc (v d nh n ung)

-

-

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Mi trng tn hnh cc hot ng th nghim hoc tiu chun phi khng lm sai lch cc kt qu hoc nh hng khng tt n chnh xc ca php o. Cn c bit quan tm n mi trng ca cc hot ng th nghim, hiu chun tin hnh hin trng nhiu hn l cc iu kin sn c trong phng th nghim. Phng th nghim phi c c phng tin theo di (cc phng tin ny phi c hiu chun), kim sot v ghi chp c hiu qu cc iu kin ca mi trng mt cch thch hp. Cn ch n cc yu t v d nh s v trng, bi, s nhim t trng, m, in p, nhit , m thanh, bin dao ng cng phi thch hp vi cc php th/hiu chun c tin hnh. a) nh sng C nhiu tranh lun v tm quan trng ca nh sng t nhin trong phng th nghim. Cc ca s s to nh sng nhng cng gy nn s mt tp trung ca nhn vin do cc s kin xy ra bn ngoi tc ng nn. Nhn chung, tng din tch lm vic bn trong l khng n nh v thng thng v ph thuc vo cc chc nng. Theo l thuyt, vic thiu cc ca s c th gii quyt bng vic thng gi, chiu sng, la chn b mt v mu sc ca tng nhng hu ht cc phng th nghim u xem y nh l vic tiu tn khng cn thit. Hai vn do nh sng t nhin mang li l chi v bc x nhit t nh sng trc tip. Mt vi ha cht c th tr nn nguy him nu b tc ng ca nh nng trong mt khong thi gian di. Thm vo , mt vi dng c khng th chu c nh nng trc tip. Nhng vn ny c th c gii quyt bng mt trong cc cch nh: dng mi che bn ngoi, ca l sch, rm ca hay knh phn chiu. Tuy nhin khng c cch gii quyt no l hon ho c, mi bin php u c mt hoc nhiu iu khng thun li. V d nh ca l sch v rm ca s l ni thun li cho bi bm vo. C th c mt vi vn v chi ca nh sng nhng ngi ta c th d dng xc nh c cng sng thch hp v bng cch s dng cc b mt khng phn chiu trong phng th nghim. Mt ln na xin nhc li l cn lu n vn trnh bi. nh sng nhn to thng cn thit, m bo cng nh sng thch hp c ch th trn thit b v cc th nghim ngoi quan bng mt (nh so mu). n

33

hunh quang thng c xem l tt hn n dy tc bi v n cung cp nh sng tt hn v li t ta nhit. b) Nhit mi trng v m lin quan Hai yu t ny ca mi trng trong phng th nghim thng khng tch ri mc d trong cc trng hp ring bit, yu t ny c th quan trng hn yu t kia. V d m thng l yu cu nghim ngt trong thun ha mu th; trong khi nhit mi trng l rt quan trng i vi cc phng php th i hi th nghim mt nhit nht nh (nh trng hp nui cy vi sinh, phn ng enzyme) hoc khi dng c hay my tnh i hi phi kim sot mi trng. Trong hu ht cc trng hp, cc mc nhit v m lin quan yu cu trong thun ha mu c to ra nh cc phng thun ha c bit. Mt vi thit b nhm gim bt chi sng s lm tng thm nhit mi trng, nhng gii php duy nht ch l iu ha nhit . c) Kim sot thng gi v s nhim bn Nhu cu thng gi cho phng th nghim bao gm vic lm khng kh trong lnh vo phng th nghim cng nh y bi, kh thi v kh c ra khi phng th nghim trong qu trnh th nghim sn phm. Vic thng gi mt phng th nghim (c bit l nhng phng th nghim nh) thng t hiu qu v tn km bng vic m ca ra vo v ca s. Nhng y khng l gii php l tng, v vn bi v nhim bn thng xuyn s gy nh hng. C nhiu thun li ngay c i vi phng th nghim nh nu lp t h thng thng gi. Cc qui trnh s dng vt liu c bit l nhng vt liu to ra kh hoc bay hi nn tin hnh trong t ht, l ni c lp vi h thng thng gi. V tr cc l thot phi lu n mt ca cc cht c ht ra. Trong mt vi trng hp khi t l thot ny phi c x l chng n mn hoc gy c. Cn m bo rng ca vo ca h thng thng kh khng qu gn vi ca ra ca h thng. Cc t ht ring l hin nay (khng c ng ng dn) c sn chc nng lm sch, bng cch s dng mt h thng lc lm sch khng kh trc khi thi n vo trong phng th nghim. Mt s h thng lc mi ch c p dng trong iu34

kin ring bit v yu cu cch thc khc nhau pht huy tc dng chng n mn. Mc d vy vic p dng rng ri cc h thng lc ny ngy cng tr nn ph bin hn. H thng thng gi cho cc phng cha ng nguy c gy nhim nn c duy tr p sut khng kh i vi nhng phng tip gip v gn hnh lang khng kh c thi t vng an ton. Vic s dng cc t an ton sinh hc trong nhng khu vc ny thng l yu cu bt buc. i vi cc yu cu v iu kin phng v trng, nn s dng cc t cch ly hoc trong trng hp yu cu din tch ln hn, nn s dng h thng lc v lm sch phng. i vi mi trng khng yu cu v trng nhng phi sch bi, th c th tha mn bng h thng lc khng kh i vo. i vi nhng cng vic yu cu iu kin c bit hoc thay i h thng thng kh th phi kim tra thng xuyn m bo rng cc iu kin cn thit c tha mn. d) V sinh Nhn chung vic duy tr iu kin ca mi trng s c nh hng n cht lng ca cc kt qu lin quan. Thm ch nu tin cy ca kt qu th nghim khng b nh hng trc tip th mt ni lm vic do bn hoc ln xn s lm cho nhn vin khng tp trung v gim nng sut. Mt phng th nghim km v sinh c th do khong cch thit b, vt liu hoc h s khng thch hp. iu ny cn phi c nhn nhn, tuy nhin trong mt vi trng hp mi trng khng ngn np li do chnh thi ca nhn vin, thiu t trng hoc thiu nhit tnh vi cng vic, thiu s quan tm n cc thit b s dng v cht lng ca kt qu do h to ra. Trong bt k trng hp no, phng th nghim km v sinh thng phn nh vic qun l cng nh khng c bin php gii quyt cc vn hoc khng nhn ra vn . e) Ting n Ting n qu ln s gy nguy hi cho sc khe. My ly tm, my bm, my sng, ng c, in thoi, m thoi ni chung, v tuyn v v ting n t bn ngoi l cc vn ln cn hn ch gim cc ting n khng mong mun ny. Ting n

35

c th c truyn n cc khu vc ln cn thng qua cc c c nh, cc ng thng gi v cc tng ngn, c bit l nhng tng lng. Rt nhiu tc ng ca ting n trong phng th nghim c th c hn ch, gim thiu hoc t nht l kim sot nu p dng cc gii php sau:-

S dng trn nh cch m. Gii hn cc ting n n cc phng ring bit hoc to khong trng. Tri thm trn cng nhiu din tch cng tt. S dng cc tm panel rng trn cc bc tng v phng ng ca ng dn gim vn tc ca khng kh.

-

-

To iu kin v khuyn khch s dng cc thit b bo v khi ting n. S dng cc trn nh nhn to kt hp chiu sng, thng gi v ngn ting n.

4.3. AN NINH Nhn chung, ngoi thit k v qun l th nghim phi chng minh tnh thng nht trong thit k v iu hnh phng th nghim m bo an ninh v cc l do sau: Cc phng th nghim thng lin quan n cc ngun thuc phin hoc cht kch thch. Chng thng c ly trm v nhiu l do. Cc thit b t tin. Bn trm thng t nhp vo phng th nghim v sau ph hng cc thit b hoc tin nghi. H s ca phng th nghim i khi rt quan trng i vi mt vi phng th nghim. Cc tnh bo chuyn nghip c th e da an ninh ca cc phng th nghim ny. Trong mt vi phng th nghim, cc mu th chun b cho th nghim hoc hiu chun thng rt c gi tr v i khi khng th thay th c, do vy chng cn phi c bo v. (ch : Chun mc cng nhn phng th nghim i hi phng th nghim phi c cc th tc m bo bo mt kt qu v cc quyn s hu khc cho khch hng).36

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Nhn vin lm vic ban m trong cc phng th nghim, c bit l phng th nghim ring l, c bit thng c nguy c. H khng nhng bo v phng b tn cng m cn phi cung cp cc trang b cn thit gi gip trong cc trng hp khn cp.

37

QUN L CHT LNG PHNG TH NGHIM (QUALITY MANAGEMENT IN THE LABORATORY)

CHNG 5

QUN L & CHT CHUN (Equiment Management & Reference Materials)

Chng ny s: Nu ln cch qun l thit b v cht chun nh gi, t hng & a vo s dng Cch kim sot vic s dng thit b Cc ti liu lin quan n thit b

5.0. TNG QUT Mt phng th nghim cn thit phi trang b v bo qun tt tt c thit b dng c o, chun chnh, cht chun v cc phng tin ph cn thit thc hin cng vic th nghim v o lng. Nu thit b nm ngoi s kim sot, trc khi s dng vo mc ch o lng v th nghim, lnh o phng th nghim phi m bo sao cho thit b phi ph hp vi cng vic, c bo dng thch hp v c tiu chun. 5.1. THIT B

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Hu ht tt c phng th nghim u cn vi loi thit b thc hin th nghim, o lng hoc hiu chun. T thit b theo ngha rng l nhng th cn thit trong phng th nghim. Dng c khoa hc nh l knh hin vi, my quang ph hoc my phn tch tp m. -

My mc th nghim nh my o cng, my th va p, my th nn. Cm th nghim c bit th cu trc hoc ng c. Dng c o nh pan-me, vonmt hoc cn. Thit b son mu th nh my tin, my mi, my ct mu. Thit b theo di nh p k, cp nhit hoc ng h lu lng V ngay c nhng th rt n gin nh my trn, khun mu, dng c thy tinh

V vy: Nu cn thit b, nht thit phi sm. Nu c, thit b phi ph hp vi mc ch s dng. Nu a vo s dng, thit b phi c bo tr. Nu chnh xc ca thit b nh hng n tin cy ca kt qu th, thit b phi c hiu chun hoc kim nh. V thit b phi c qun l v c kim sot thng qua h thng vn bn c hiu lc. Trong ch ny, chng ta s xem xt: a) nh gi la chn, mua sm v a vo s dng thit b mi. b) Bo tr thit b.c) Kim sot vic s dng thit b d) Lp s sch ti liu v thit b phng th nghim

Chng trnh m bo thit b phng th nghim, hiu chun v dn xut chun s c nu chng 6.39

5.2. MUA SM THIT B MI Phng th nghim thng cn sm cc thit b mi. L do mua sm l v: a) Cn tng khi lng cng vic. b) M rng phm vi th nghim v o lng ca phng th nghim. c) p dng cng ngh mi. d) Thay th thit b c hao mn hoc cn loi b. Thit b mi thng t tin nn cn c u t lu di. Sai lm trong cng vic mua sm c th s gy ra phin phc v lng ph cho nhiu nm sau. Do vy lnh o cn phi nh gi v la chn cn thn m bo chn ng thit b mi cn cho mt vi hoc tt c cc nhu cu trn. 5.2.1. Pht hin nhu cu a) Chng ta mua thit b v l g? tng cng khi lng cng vic? Php th mi? Cng ngh mi? Gim chi ph? Thay th?

b) Chng ta i hi g i vi thit b mi s mua?

Tnh ph hp vi mt vi c trng k thut? Hay nhiu c trng k thut? Phm vi vn hnh? nhy, gii hn pht hin? chnh xc, tp trung, khng m bo? Tng thch vi my tnh? n gin hay phc tp?

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D h hay chc chn? Gii hn kinh ph.

5.2.2. Nu kh nng la chn a) Ai c th cung ng? Hng ch to hay i l tiu th? Trong nc hay nc ngoi? C dch v hu mi? Hng danh ting?

b) C kiu no? p ng i hi. C th la chn nhiu kh nng? Kh nng dung ha? Ch to theo yu cu ngi s dng? Ph tng thay th? Thi gian giao hng? Tng gi (k c gi tr gia tng)? Bo hnh?

5.2.3. nh gi v la chn a) Chn cch no? Tra cu ti liu. Tham vn nh cung cp. Yu cu ti liu tham kho. Hi ngi s dng qua. Quan st vn hnh.

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Trc nghim trong phng th nghim kim nghim s dng th.

b) nh gi ci g? p ng hon ton yu cu? Phm vi vn hnh? nhy, gii hn pht hin? chnh xc, tp trung, khng m bo? Thi gian khi ng (vn hnh)? Vn hnh thng sut? Tng thch vi my tnh? Chi ph vn hnh?

c) Cc chun mc khc Sch hng dn s dng v bo tr? Nhc im v thit k? Tnh d s dng? Yu cu c bit v mi trng? Gy n, rung ng hoc x khi? An ton? Lp va phng th nghim? S phi sa i g khng? S dng di lu?

5.2.4. Qu trnh quyt nh a) Gi n t hng, nhng Nh ng tm tt bt c iu g v nn nu chi tit cn thit

trong n t hng.42

Nh nu yu cu bo hnh bng giy t.

b) Sau khi thit b nhn v Hy lp t cn thn. nh gi y . Tin hnh hiu chun nu cn thit. ng tr ht tin khi my cha lp t v vn hnh.

c) Trc khi ht hn bo hnh nh gi li ton din thit b. Thng bo cho nh cung cp bng vn bn

5.3. A VO VN HNH Mua xong thit b cha phi xong, cn phi a vo vn hnh thit b sao cho n hot ng hon ton v tr thnh mt b phn tin cy ca ton b thit b phng th nghim. 5.3.1. Lp t Chn ni thch hp. To mi kh nng dch v thit b. Kim tra k cng thit b. 5.3.2. a vo vn hnh nh du thng nht d nhn dng thit b (i vi tt c thit b quan trng v cht chun). a vo danh mc kim k. Qui trnh trch nhim. Hiu chun (nu cn thit). Vit thnh vn bn trnh t vn hnh. Vit thnh vn bn qui nh an ton.

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Hng dn nhn vin vn hnh. Xy dng th tc kim sot cht lng. Xy dng chng trnh bo m o lng. Xy dng k hoch bo tr. 5.4. BO TR Mt khi c thit b mi, cn phi xy dng k hoch bo tr. 5.4.1. K hoch bo tr a) V sao phi c k hoch

ko di tui th thit b. To tin cy. Hn ch s c. Bo m lun c thit b s dng.

b) Lc no tin hnh bo tr? Chng trnh thng xuyn. Theo thi gian hoc theo mc s dng. Theo thi v cng vic trong nm.

c) Vic bo tr i hi g? Ty thuc thit b. Lau chi. Tra du m. Kim tra iu kin. Xem cc chi tit (chuyn) ng. Kim tra phn in t.

d) Bo tr nh th no?

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Tham kho sch hng dn ca hng ch to. Thu thp kinh nghim. Hi ngi s dng qua. Vit qui trnh hng dn. Lp phiu kim tra (cheklist)

e) Ai lm vic bo tr? i l dch v: - c hun luyn v c nng lc. - Theo hp ng dch v. - lm mt thi gi ca i ng. Nhng: - Khng phi lc no cng c. - Khng p ng kp thi. - Lun t . Nhn vin PTN: - V quyn li thit thc. - Bt c lc no. - Lun r hn. Nhng: - nh hng n cng tc chuyn mn. - Cha c tp hun c bit. - C th gy nhiu chuyn khng lng. f) Bo tr u? Ti PTN: - iu nn lm. - C th xem ngi bo tr tn g. - Trnh khu vn chuyn gy h hi. - t tn thi gian. Ti xng i l: - i khi cng cn thit. - C dng c chuyn dng.

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- Mi trng thch hp. 5.4.2. H s bo tr Lp l lch cho mi thit b. Ghi chp chi tit ca mi ln bo tr. Ghi h hng v sa ci g. Xc nh chi ph. 5.4.3. H thng k hoch Thng bng cch no? Chu k ln k tip. Thi gian . Xem xt nh k. 5.5. MY TNH Khi s dng my tnh c nhn l tr trc tip d liu hoc kim sot vn hnh, phng th nghim cn chng t rng ton b h thng l thch hp. Tnh chnh xc v tc tnh, gp phn chnh vo tnh thch hp ca thit b. Tn hiu o c pht hin phi ph hp vi chnh xc cn thit trong ton dy o. H thng phi tch ly d liu bo m rng cc gi tr i hi phi c ghi nhn v b nh phi sc lu gi cc d liu c sn sinh. Cc h thng phi thng bo cho ngi s dng cc giai on ca qu trnh ang din ra bnh thng. Cc chng trnh phi gip ngi vn hnh nhn ra sai li hoc s gin on. Phn mm cng cn s bo tr thng xuyn. Cc chng trnh c ci bin v m rng phi c kh nng p dng th. Cc kt qu ca php th phi c chng trnh lu gi v lin kt vi l lch bo tr. 5.6. KIM SOT S DNG THIT B H thng qun l thit b phi y chi tit bo m rng mt nhn vin bit c tnh trng hin ti ca mi thit b h cn s dng.46

Nhn vin cn phi bit: Tnh trng hot ng hin thi ca thit b. Nhng gii hn s dng. Tnh trng hiu chun hin hnh.

5.6.1. Tnh trng hot ng hin thi Thit b mi sm ch c s dng khi vic lp t v vn hnh th kt thc. Thit b sai hng khng c dng nu cha hon thnh vic sa cha. Thit b ht thi hn hiu lc hiu chun th khng c s dng. Khi pht hin vic s dng thit b ht hn tiu chun, b h hng hoc c xc nh khng hp php, phng th nghim phi xem xt li hu qu i vi kt qu th ca trong thi gian trc . 5.6.2. C cu kim sot H thng h s ca thit b s phi cha ng nhng chi tit v tnh trng vn hnh hin thi ca mi thit b, nhng mi nhn vin phng th nghim cn phi c thng bo ngay tc khc hoc nhng lu qua cc hnh thc: a) C lp b) Bng ch dn treo tng c) Dn nhn - Rt cc b phn h hng. - Gn ni t thit b. - Vn hnh hon ton. - Hn ch s dng. - Cm s dng. d) nh bn, dn nhn thng bo tnh trng i vi chi tit nh (th d ch r ngy kim nh cui cng hoc thi hn kim nh ti). Hy nh rng mu sc rt c ch tnh trng thit b. Cc nhn hoc bng c in bng nhng mu sc khc nhau lm nhn vin ch v tnh trng vn hnh ca mi thit b. 5.7 LP VN BN THIT B

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Mun h thng qun l thit b c hiu qu, nht thit phi lp thnh vn bn v cc chi tit ca tng thit b, qui trnh vn hnh, bo tr bo dng, vic hiu chun v c chng trnh bo m cht lng. H thng vn bn ny gm:

Bn kim k thit b. Nhng hng dn vn hnh ca nh ch to. Qui trnh bo tr v h s bo tr. Hiu chun v h s hiu chun. C ch nhc nh (call-up-mechanisms)

5.7.1. Cng tc kim k kim sot v qun l thit b, trc ht phng th nghim phi bit mnh c thit b g. iu c ngha l phng th nghim phi thit lp mt h thng ghi nhn tt c nhng thng tin v thit b mnh c hoc mi mua. H thng kim k ny phi c xy dng nhm p ng nhu cu ca phng th nghim. H thng ny x l khc nhau i vi cc thit b ln v nh hoc r tin mau hng. a) Thit b chnh Tn, kiu. S lot sn xut. Nh ch to iu kin ghi nhn. Ngi tip th, ngi bn. Ngi dch v bo tr. Ngy nhn v bo tr. Thng tin v bo hnh. Gi. M s thit b.48

V tr trong phng th nghim. Tm lc lch s v bo tr v hiu chun (k c hng hc, s

c, ci tin, sa cha). Ngy thanh l, ngng s dng.

(Nhng yu cu trong ISO/IEC Guide 25:1990) b) Nhng thit b nh v r tin mau hng (minor) nh dng thit b. Ngun cung cp. Vic s dng. S lng thng xuyn trong kho vt t trong kho vt t. S lng t hng b sung. Qui nh c hng b sung.

Thng thng, ph trch phng th nghim phi kim k v lu tr s sch. nhiu phng th nghim, h s v cc thit b nh, r tin mau hng c bo qun ti kho v ngi th kho kim sot hoc nhn vin phng th nghim s cp nht mi khi h ly s dng. 5.7.2. H thng bo tr Phi c h thng bo tr chnh thc i vi tt c cc thit b chnh yu. H thng ny phi bao gm h s cho mi thit b v: Nhn dng thit b. Chng trnh bo tr. Nhng cng vic bo tr do cng ty bo tr thc hin. Nhng cng vic bo tr do phng th nghim thc hin. Qui trnh bo tr. Kim tra chc nng.

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H s ghi chp sai hng v sa cha. H s cng vic bo tr n gin. Kim sot v dn nhn. Nhng h s ny c th theo mu ca s tay bo tr, nhng phi lin kt s hiu chun hoc lm c hai s tay, nhng i khi cng tm thy s tay phng php. 5.7.3. H thng hiu chun v m bo o lng Phi ghi vo h s ton b chi tit v h thng hiu chun v m bo o lng i vi tng thit b. Thng thng nhng h s ny tng t v bn cht v cch trnh by nh h s bo tr. Chng sau s cp c th v ni dung h s loi ny. 5.7.4. C ch nhc nh (call-up-mechanisas) H thng qun l thit b c hiu qu hay khng cng nh vo vic h thng (qun l) t n phi c c c ch nhc nh thch hp. Nhng nhn vin phng th nghim chu trch nhim bo tr hoc hiu chun thit b khng th lm vic bng tr nh. Vy h thng (qun l) phi gip h trong nhng trng hp cn ch n cc thit b ring l. H thng qun l phi tnh in ch dn v thi gian khi trin khai bo tr hoc hiu chun. H thng s c cung cp cho h nhng ch dn trc cho php nhng vic cn lm kp thi. C ch nhc nh c th di dng sau: Bng ghi, s ghi (thng khng tin cy). K hoch cng vic hng ngy (qui nh cho mt nm). T giy dn tng (d nhn thy nhng hn ch phm vi). B th (d mt hoc b qun u ). a vo my tnh (c l tt nht). Cho d chn cch no th cn thit phi cp nht h s mt khi cng tc bo tr hoc hiu chun hon tt.

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5.7.5. Qun l h thng Mi phng th nghim phi t xy dng cho mnh mt h thng h s thch hp vi iu kin ring ca n. Mt h thng thch hp i vi mt phng th nghim ny c th rt phc tp i vi phng th nghim khc hoc mt h thng c th hu hiu mt phng th nghim nh nhng khng hu hiu mt phng th nghim ln. Khi xy dng mt h thng qun l h s, phng th nghim nn xem xt: a) Tnh d p dng h thng cng n gin cng tt! b) Tnh d cp nht h thng cng n gin cng tt! c) Tnh d cp nht nhn vin s v hiu qu nu c thay i. d) S phn phi c la chn h s no cn c qun l tp trung, h s no do phng th nghim qun l? e) Giao trch nhim ai s c trch nhim bo qun v cp nht h s? 5.8. TM TT Vic qun l c hiu qu thit b v cht chun trong mt phng th nghim i hi phi: a) Mua sm thit b mi trn c s nhn bit c nhu cu;b) Cha nn mua sm thit b chng no cha nh gi nghim tc liu thit b

c tha mn yu cu ca phng th nghim hay khng? c) Lp t v a vo vn hnh trc khi chnh thc s dng cho mc ch;d) Thit b ln v chnh yu cn phi c bo tr v hiu chun.

e) Phi vit thnh vn bn cc qui trnh vn hnh, bi tr v hiu chun i vi cc thit b ln v chnh yu; f) Nhn vin th nghim phi nhn thc y v tnh trng vn hnh ca thit b nh s dng;g) Nhng h s ring cho tng thit b v cht chun phi c lu gi vo h

s kim k thit b, ghi li lai lch ca cng vic bo tr, hiu chun cc thit b ln v chnh yu;51

h) Trn ht, h thng qun l phi c xy dng sao cho c th tha mn nhng nhu cu thc s ca phng th nghim v phi tht n gin trong thao tc v duy tr.

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QUN L CHT LNG PHNG TH NGHIM (QUALITY MANAGEMENT IN THE LABORATORY)

CHNG 6

O LNG, LIN KT CHUN & HIU CHUN(Measurement, Traceability & Calibration)

Ch ny gip hc vin: - Hiu c cc khi nim v hiu chun - Xy dng v p dng chng trnh m bo o lng phng th nghim v - Cc phng thc cng h thng hiu chun o lng

6.0. HIU CHUN V LIN KT CHUN TCVN 5958-ISO/IEC Guide 25:1990 yu cu - Tt c cc trang thit b o lng v th nghim c nh hng n chnh xc hoc hiu lc ca cc cng vic hiu chun hoc th nghim phi c hiu chun v hoc kim nh trc khi a vo s dng. Phng th nghim phi lp chng trnh hiu chun v kim nh phng tin o v th nghim ca mnh Chng trnh phi c xy dng v iu hnh m bo cc php o do phng th nghim thc hin u c ni vi chun quc gia, nu c. Giy chng nhn hiu chun phi ch r tnh dn xut vi chun quc gia v phi cung cp cc kt qu o v khng m bo.

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- Gia cc ln hiu chun v kim nh, cc chun chnh v trang thit b o lng, th nghim phi c kim tra thch hp - Gia cc ln hiu chun v kim nh, cc chun chnh v trang thit b o lng, th nghim phi c kim tra thch hp. Theo , phng th nghim cn phi thit lp mt chng trnh m bo o lng. Chng trnh m bo o lng. C mc tiu: m bo rng cc kt qu o lng, th nghim phi t chnh xc thch ng. Vi mc ch: To lng tin cho ngi s dng kt qu th nghim. S dng cc kt qu th nghim ng phc v kim tra cht lng

nguyn/vt liu, sn phm hng ha; cung cp cc thng tin xc ng cho cng tc nghin cu, nh gi cc n, cng trnh hoc cho cc dch v php l v dn s. C phm vi: Theo mc ch ca php o v php th. Khng vt qu mc chnh xc hay tin cy cn thit. Cho tt c cc lnh vc, khu vc hot ng m cht lng kt qu th

nghim c nh hng. 6.1. NH NGHA V KHI NIM Hiu cc nh ngha v khi nim s gip cho lnh o phng th nghim c hnh ng ng. Cc nh ngha di y c trnh by trong TCVN 5958:1995, TCVN 5814:1994 v trong mt s ti liu mi nht. Hiu chun (Calibration) Tp hp cc thao tc xc minh, trong iu kin qui nh, quan h gia cc gi tr c ch bi phng tin do hoc gia gi tr c th hin bng vt o vi cc gi tr tng ng bit ca i lng cn o.54

L vic so snh gi tr ca i lng th hin bng phng tin o vi gi tr tng ng th hin bng chun o lng. Php lnh o lng (d tho 1999) Kim nh (Verification) S khng nh qua vic kim tra v cung cp cc bng chng rng cc yu cu qui nh c tha mn. TCVN 5958 L vic xc nh v chng nhn ca t chc c thm quyn i vi phng tin o p ng y cc yu cu qui nh. Php lnh o lng (d tho 1999) Cn lu rng c hai khi nim trn c ngha ring khc. Trc y, t chc tiu chun quc t dng t Validation kim tra s ng n thay c hai. a s cc nc, vn hiu chun c t ra cho tt c cc hot ng, cn kim nh ch gii hn mt s phng tin quan trng dng trong thng mi. nc ta, kim nh l bt buc i vi cc phng tin o dng trong thng mi hoc c lin quan n an ton v sc khe, lao ng v mi trng hoc dng cho hot ng php l, cn hiu chun l t nguyn v phc v cho sn xut, nghin cu khoa hc. S lin kt chun hay tnh lin kt chun (Traceabitily) c th ca kt qu php o c th lin h n cc chun quc gia thng qua mt chui so snh khng t on. Ghi ch: Ni chung khi nim dn xut chun m ch vic lin h vi chui chui quc gia quc t tng ng trong o lng. TCVN 5958:1995 S dng thut ng dn xut chun thay v thut ng lin kt chun khng m bo o (xem chng khng m bo o) 6.2. CC H THNG HIU CHUN H thng hiu chun

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Mt h thng qun l nhm bo m rng, khi thc hin php o, khng bo m do thit b o gy ra c nh lng v ph hp vi yu cu xc nh ca php o. Cc yu cu: ng, chnh xc v khng m bo o c qui nh bi: - Khch hng - c tnh k thut - Phng php th - Thit b - Phng th nghim 6.3. CC TIU CHUN V H THNG HIU CHUN Mt s c quan quc gia v quc t bin son tiu chun ban hnh cc tiu chun m t cch thc thit k, thit lp v duy tr h thng hiu chun, l: MIL-C-45662A M) BS 5781 : 1979 ASS 3912 hoc ISO 10012 Cc yu cu bo m cht lng i vi thit b o. H thng o lng v ghiu chun (Vin tiu chun Anh) Cc yu cu i vi h thng hiu chun (Tiu chun qun i

Tt c cc tiu chun v h thng hiu chun tha nhn rng: a. Mc ch ca hiu chun l to lng tin trong o lng.b. Phi thit k h thng sao cho cc nhu cu ca phng th nghim c p

ng. c. H thng phi thch ng c nhng thay i ca nhu cu. d. H thng phi c kh nng pht hin ngay nhng sai st v ch r nhng hnh ng kp thi hiu chun sai st. e. H thng phi to c kh nng lin kt chun n h thng chun quc gia (v cui cng n h thng chun quc t)56

6.4. PHNG THC HIU CHUN Vic hiu chun thit b c thc hin theo mt trong 3 phng thc sau (hoc kt hp): a) Phng php hiu chun vt l (physical calibration) Cc dng c hot ng da trn c tnh vt l nh khong cch, khi lng, p dng, nhit , lc, o in, t trng hoc suy din t cc c tnh trn, u thuc vo phng thc ny. Theo hiu chun dng c phng th nghim l s so snh chng vi dng c c chnh xc cao hn (thng t 3 n 10 ln) xc nh khng bo m o do thit b gy ra. b) Phng thc so snh (comparative techniques) Phng thc ny dng cc cht c thnh phn hoc c tnh bit trc (cht v vt liu chun) xy dng ng c tuyn ca phng tin o. ng c tuyn s so snh gi tr c trn phng tin o vi cc gi tr ca cc cht chun. Phng thc ny p dng cho cc thit b, dng c nh ph k, quang ph k, sc k, my phn tch t ng, pH k hoc my o in dn Phng thc hiu chun mt s loi thit b o cng cng thuc loi ny v vt chun dng y (lm chun cng) khng phi l s suy din (dn xut) t mt chun vt l o lng. c) Phng thc so snh lin phng (interlaboratory comparisons) Khi c 2 phng thc trn khng th p dng, cch duy nht c th c c hiu chun (xc nh cng) ca thit b l s so snh lin phng thng xuyn. Thuc loi ny l cc phng thc hiu chun cc thit b kim nghim y t, cc php hiu chun cc thit b chun cao nht ca cc quc gia vi nhau. 6.5. LIN KT CHUN (HIU CHUN VT L)

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M hnh l tng Vin cn o quc t BIPM Phng hiu chun quc gia Cc phng hiu chun c cng nhn Ngi s dng phng tin o (PTN)

V m hnh thc t

Phng hiu chun quc gia Cc phng hiu chun c cng nhn Ngi s dng phng tin o (PTN)

a) Trong cc m hnh nu trn, vic lin kt chun t c thng qua mng

li cc phng th nghim (tt hn ht l c cng nhn) ni tip lin tc (khng t on) t ngi s dng phng tin o (phng th nghim) cho n phng hiu chun o lng quc gia v ngay c cho phng o lng quc t. Mt nc quc gia c c h thng y v lin tc. Tuy nhin c th thiu mt s php hiu chun c bit bc cao. Nu h thng y , cn thit phi ni kt bc cc phng th nghim vi nhau (khng theo th t cao thp k tip) b) Chun v cht chun, nu c th, phi c lin kt chun t chun o lng quc gia hoc cht chun, tuyt i khng dng cho mc ch no khc. Cc chun ny phi c hiu chun bi c quan c nng lc c lin kt vi cc chun quc gia hoc quc t. 6.6. CCH TIP CN HIU CHUN

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Trc y v c hin nay, do hn ch nhn thc, phng th nghim quan nim v hiu chun theo nhiu cch khc nhau, i khi mang tnh ch quan hoc thiu ng n l: Hiu chun l cng vic ca nh sn xut phng tin o kim.

iu ny cha dng hon ton. i khi vic hiu chun ch l hnh thc hoc thiu c s tin cy (ty theo tng quc gia). Hn na cc yu t v vn chuyn, thay i iu kin mi trng v s dng s lm mt hiu lc ca hiu chun, cho d c Giy chng nhn. T chc vic hiu chun ngay sau khi nhn phng tin Cch thc ny hon ton ng v cc hng cung ng thng m nhn (commissioning) hoc yu cu phng hiu chun s ti thc hin. Nhng nh th vn cha . T chc hiu chun nh k theo mt chu k nh trc. iu quan trng l xc

nh chu k nh th no. Nhiu phng th nghim hon ton ph thc vo c quan (Phng) hiu chun bn ngoi khi h hiu chun. Hn na, phng th nghim cng d dng tin vo chu k do bn ngoi qui nh, ngay c khi t mnh tin hnh hiu chun. Cch tip cn hp l v ph hp vi cc yu cu i vi mt phng th nghim c cng nhn phi l s theo di thng xuyn s hot ng ca thit b o lng th nghim. Ni cch khc l lnh o phng th nghim khng ch p dng mt trong cc cch thc nu trn, m phi kt hp chng, v iu cn thit l phi kim sot (thng qua theo di) tnh trng hot ng ca phng tin. Cch tip cn ny phi th hin trong chng trnh m bo o lng phng th nghim. 6.7. THEO DI HOT NG CA THIT B (Chng trnh bo m o lng phng th nghim) Mt h thng qun l thit b cn phi c xy dng sao cho khng ch c cc php tiu chun chnh yu c thc hin theo cc chu k thch hp m vic kim tra s hot ng ca thit b cng phi tin hnh thng xuyn nu c th bo m tin cy lin tc ca cc php o. Chng trnh bo m o lng (CTBL) bao gm cng nhiu cng tt cc yu t sau:59

* a vo khai thc thit b (commisioning) Hiu chun ban u Kim tra ban u * Kim tra tnh nng hot ng (operational checks) Vic kim tra u n nh k (thng l kim tra qua bng mt v khng cn ghi h s) Tin hnh hng ngy, hng tun hoc trc khi s dng (th d s dng thng xuyn cc chun o lng, cht chun, mu trng dung dch im pH, my m phng x) * Kim tra nh k (periodic checks) Cn kim tra m rng nhiu hn i vi chnh xc v hot ng ca thit b vi chu k di hn (th d, so snh vi cc thit b khc vi chu k 6 thng nhng thit b o nh nhit k chng hn) * Bo tr thng xuyn c tnh phng nga (routine preventive maintenance) * Ti hiu chun ton b (complete recalibration) * Ghi chp v phn tch d liu lch s nhm mc ch on trc xu hng (theo di s tri ca ch th) 6.8. MT TH D V CHNG TRNH BL CN IN T * a vo s dng (khai thc) Hiu chun ton din: v cng, lp li, tuyn tnh, sai s gc, kim tra qu cn mc (lp) sn * Kim tra tnh nng hot ng Mc cn bng ca cn trn bn Kim tra im khng mi khi cn * Kim tra nh k Hng thng: kim tra cc thang o bng qu cn chun (n gin hn hiu chun)

60

Chu k 6 thng: kim tra lp li * Bo tr Hng nm hoc 6 thng mt ln nu b bm bi hoc c du hiu st r, n mn do mi trng. * Ti hiu chun 3 ln trong mt nm hoc theo kinh nghm * Phn tch d liu Tp hp tt c d liu kim tra Phn tch cc d liu Ghi ch: Khi tp hp cc d liu v lch s, nu xc nh sc xu hng suy gim v cng, chnh xc v khng m bo, cn iu chnh thi gian cc khu, nht l khu hiu chun nh k. 6.9. NHNG U IM CA CHNG TRNH BL - Bit c s tri ca thit b, thay i tnh nng hot ng hoc h hng - Bo m tin cy ca kt qu o mi lc - Xc nh chu k hiu chun thch hp. 6.10. TI HIU CHUN C BIT a) p dng i vi - Dng c o khng dng ton b dy o. - Dng c o khng s dng trong phm vi gii hn - Dng c o b h cp chnh xc b) Li ch - Ch ti hiu chun lin h mt ht n nhu cu ca PTN - Gim chi ph hiu chun c) Nhng ri ro

61

- Nhng cng vic mi v khn c th cn s m rng phm vi vn hnh hoc phm vi s dng nhm gii hn lp li. - Cc thit b b loi c th cn phi em s dng li. d) Cn phi kim sot - H s bo m thit b 6.11. HIU CHUN TI PHNG TH NGHIM (NI B) Ch c nhng ngi c giao quyn v c o to tng xng mi c tin hnh cc php hiu chun ni b v cc cng vic kim tra hoc so snh lin phng. Tt c cc qui trnh ny phi nu r cc phm vi chp nhn hoc cc gi tr chp nhn cng cc hng dn hiu chnh nu cn. i vi cc php hiu chun hay kim nh ni b, qui trnh phi qui nh: a) Ghi vo h s cc d liu b) Ghi c n v cc d liu c) H s phi k tn v ngy d) Ghi r cht chun hay phng tin o chun c dng hiu chun (v xc nhn chng phi c hiu chun trc ). 6.12. HIU CHUN BNG CHT CHUN Nu phi dng cht chun c chng nhn (hoc cha c chng nhn nhng so snh) phng th nghim cn phi chng t rng: a) Cc cht chun phi tin hnh hiu chun trn ton phm vi ; b) Cc h s phi c lu gi nhn din v ngun gc cht chun; c) Ton b ti liu v cc gi tr c chng nhn cht chun phi lu gi; d) Cc ti liu v cc gi tr c chng nhn phi bao gm c chi tit v cch thc kim tra s ng n ca cc gi tr c chng nhn. 6.13. HIU CHUN H THNG KIM NGHIM C MY TNH - C th pht sinh nhiu kh khn c bit nu cc tn hiu nhp hc xut ca mt thnh phn no khng th truy cp.

62

- Nu c th cch ly tng thit b khi h thng x l d liu, ngi ta c th hiu chun thit b bng nhng phng php thng thng ng thi kim tra s ng n ca h thng x l d liu mt cch ring bit bng cch ci t cc b chuyn i A/D v h thng giao din. - Nu khng th cch ly thit b, phi hiu chun ton b h thng trong tng th. - Cc phn mm c cung cp sn cng vi thit b hay phn mm do phng th nghim thit lp cng phi c x l tng t chng hot ng khng sai li - Trong nhiu trng hp, c nhng phn mm chun cha ng cc d liu th nhm kim tra h thng. - Cn ch , cc phn mm chun phi bao trm ton b phm vi lm vic ca thit b v c kh nng lin hp cc tnh hung ring l pht hin cc sai li v tnh logic ca chng trnh hoc tiu chng trnh. 6.14. CHU K HIU CHUN Cn ch cc yu t: - Kiu thit b - Khuyn co ca nh sn xut - Phng php th chun - Cc d liu v xu hng - Mi trng - chnh xc ca php o - Cc yu cu ca c quan cng nhn phng th nghim 6.15. C CH NHC NH Qun l phng th nghim cn c cch thc nhc nh v thi gian, trch nhim v cch thc thc hin cc cng vic lin quan n chng trnh m bo o lng phng th nghim. 6.16. TM TT

63

Mi phng th nghim u cn mt h thng bo m o to s tin tng vo kt qu th nghim khi thng bo cho khch hng hay cho mc ch ni b. Mi h thng kim tra s ng n ca phng tin o lng th nghim phi: a) Hiu chun thit b mt cch h thng nhm bit c mt cch chc chn sai s ca php o hoc php th. b) Kim tra xc nhn s ph hp ca thit b vi cc yu cu qui nh; c) To c tnh lin kt chun vi chun quc gia hoc chun quc t; d) c h tr bi chng trnh bo m o lng nhm theo di tin cy ca thit b v dng c cn thit cho vic o v th nghim.

64

QUN L CHT LNG PHNG TH NGHM (QUALITY MANAGEMENT IN THE LABORATORY)

CHNG 7

PHNG PHP TH

(Test Methods)

Chng ny s: - Gii thch cc loi phng php th - Trnh by vic qun l v p dng cc phng php th - v kim sot vic s dng cc ti liu ny

7.0. PHNG PHP TH Phng php th l c s tin hnh cc hot ng o lng, th nghim hoc tiu chun. Vic s dng cc phng php th khng ging nhau hoc vic khng tun th cc phng php th c qui nh thng dn n cc sai bit v tranh ci.

65

Vic lp vn bn v kim sot cc phng php th dng trong phng th nghim l cn thit t c cc kt qu ng tin cy; do : Tt c phng php th phi c vit thnh vn bn; Tt c phng php phi c duy tr, cp nht v sn c cho nhn vin 7.1. CC LOI PHNG PHP TH Ty theo bn cht ca cng vic v yu cu ca khch hng m phng th nghim c th s dng:

Phng php th tiu chun (standard methods) do cc c quan tiu chun quc gia hoc quc t bin son v cng b, nh ISO, ASTM, BSI, AOAC, TCVN

Phng php th c cng b (published methods) do cc nh khoa hc xy dng v cng b trong cc tp ch hoc cc ti liu khoa hc.

Phng php th ni b (in-house methods) do phng th nghim t bin son p ng cc nhu cu ring ca mnh.

7.2. PHNG PHP TH TIU CHUN a) u im c tha nhn v tip nhn trong nc hoc quc t Cho php so snh kt qu gia cc phng th nghim khc nhau Khng cn ti o to nhn vin khi di chuyn ni lm vic c th nghim trc khi s dng, t gy ri ro Lun cho cc d liu v chnh xc, tp trung v khng m bo o t cc th nghim gia cc phng th nghim Lun c sot xt v cp nht nh s phn hi D dng ng dng vo cc phng th nghim. b) Nhc im Khng chuyn su66

Kh c p dng trc tip trn cc mu th phng th nghim hoc theo nhu cu th nghim

t khi i din cho cng ngh hin i v c quan bin son sot xt thn trng v chm

Thng qu phc tp, chnh xc, chm chp hoc tn km cho mc ch ca phng th nghim

Nhiu tiu chun quc t khng lun sn c.

7.3. PHNG PHP TH C CNG B a) u im

Thng st thc vi cng ngh hin hnh

Thng st thc vi nhu cu ca phng th nghim b) Nhc im Thng xut hin mt phng th nghim, khng c hiu lc nu em so snh lin phng. Cc d liu v chnh xc v tp trung thng khng c cung cp hoc khng ng tin cy Thng phi xy dng hoc b sung nhiu ph hp vi nhu cu ca phng th nghim Thng t c chp nhn rng ri trong nc hoc quc t Him khi c xem xt hoc sa i v khng c phn hi ca ngi s dng. 7.4. PHNG PHP TH NI B a) u im c xy dng nhm p ng nhu cu ca phng th nghim trn c s nng lc hin c. c xy dng cho mt cng vic hay mt loi mu th c th. Thng t tn km v nhanh hn

67

D c sot xt sa i v cp nht b) Nhc im t c chp nhn trong nc hoc quc t

c son cho mc ch qui nh, nhng c th p dng mt cch sai tri cho cc mc ch khc.

t hoc khng c cc d liu v chnh xc, tp trung hoc khng m bo o.

Thng khng c hiu lc th nghim so snh lin phng

Cha ng nhiu vn , v c s l thuyt kh hiu.

7.5. LA CHN PHNG PHP a) Ai quyt nh hoc chn phng php no? Yu cu lut php? S mong i ca cng ng? Yu cu c bit ca khch hng? Thay i iu kin phng th nghim? Tng hay gim chnh xc hoc tp trung? Nhp thit b mi hoc cng ngh mi? Cn gim chi ph hoc tng tc th? Cc phng php hin thi khng tha mn. b) Chn la phng php:

Phng th nghim thc hin bt k php th no c nhiu hn mt phng php phi ghi vo bin bn l do la chn phng php tr phi khch hng khng yu cu. Phi ghi chi tit da trn c s chn mt phng php c th v tnh trng no phng php c chn.

7.6. GII THIU MT PHNG PHP a) Xem xt ban u68

Ti sao phng php ny cn thit? Ai s s dng kt qu v nhm mc ch g? y l php th mi hoc s thay th php th hin hnh? Cn dng c o mi hoc cn hiu chun b sung? Cn thm nhn lc hoc hun luyn b sung? Cn thm cc dch v th nghim hoc ngun lc khc? Th thng xuyn hay ch th mt ln hoc lu lu mi th? Hp ng vi phng th nghim khc c hay hn khng? b) Th nghim c gii hn

Tin hnh php th d dng hay kh khn?

Tc thc hin? thi gian thc hin?

Chi ph thc hin gi cng, thit b - dng c s dng hoc cc chi ph khc?

i hi k nng hoc tay ngh c bit? Cn c bin php an ton g?

tin cy ca phng php?

Phng php p ng c nhu cu phng th nghim? c) nh gi y Dng nhiu ngi th nghim xc nh tp trung

Kim tra bit chnh xc v mc pht hin

d) Thc hin Lp thnh vn bn phng php th Hun luyn nhn vin th nghim Xy dng chun mc kim tra cht lng

D kin sot xt sau ny (t nht sau mt nm)69

7.7. S TAY PHNG PHP TH Trong cc trng hp, phng php th tiu chun m t chi tit tt c php th, v c cc qui trnh lin quan, l th s tay cht lng ca phng th nghim phi lit k tn v ni lu gi cc phng php ny. Trong cc trng hp khc, th ti liu phi ng nh vic bin son s tay phng php th da trn cc hot ng th nghim ca phng th nghim. S tay phng php th phi bao gm: oo o

Phng php th ni b Phng php c cng b Phng php ci bin t phng php th tiu chun Hng dn v th nghim

o

Ngay c i vi nhng phng, th nghim thng s dng phng php th tiu chun, cng cn phi vit li cc phng php th ring cho mnh, bi l: o Phng php th tiu chun thng bao qut nn cha ng

nhiu im khng cn thit cho iu kin phng th nghim o Phng php th tiu chun i khi m t nhiu qui trnh la

chn, nhng i vi mt phng th nghim c th li khng tng ng v khng th chp nhn c hoc thm ch khng cho php p dng; o Phng php th tiu chun c khi li khng vit y m ch

vin dn cc phng php th tiu chun khc; o Phng php th tiu chun c trnh by i dng m nhn

vin phng th nghim khng d dng s dng; o Phng php th tiu chun khng th nu c th thit b c

th c dng cho mt phng th nghim ring bit no hoc nu cc qui trnh ring bit cho vic x l mu hoc kt qu th; o Phng php th tiu chun qu t hoc i khi khng d dng

mua c. 7.8. NI DUNG S TAY PHNG PHP TH70

Mi phng php th trong s tay phi cha ng cc thng tin sau: Tiu Ngy ban hnh Vic y quyn s dng Bng tra cu

Ti liu tham cu (vi vic thng bo v s sai bit)

Nguyn l Phm vi p dng

Nhng hn ch s dng (th d phm vi o, cc tr ngi hoc cc yu t mi trng)

Cc qui trnh v an ton Cc yu cu v mu Cc yu cu thit b Ha cht cn dng Cc qui trnh th nghim Cch tnh ton (cc v d) Ghi chp v h s chnh xc, tp trung, khng m bo (k c qui trnh thit lp v trnh by khng m bo o) Cc qui trnh kim sot cht lng Cc vn gp phi, cc hnh ng khc phc Tay ngh ca nhn vin v yu cu o to Cc thng tin c ch khc v phng php, cc v d v cc bin bn lm vic cng nh bo co s b th nghim.

71

Cc phng php th tiu chun do cc t chc tiu chun quc gia hoc quc t bin son u cha ng cc thng tin nu trn. Nhng phng php nh vy khng nht thit phi nh my li m c th c s dng nguyn bn gc, c km theo bt k mt thng tin b sung no cn thit. Cc phng php th ni b v cc phng php th c cng b a) C th c dng nu khng c phng php th tiu chun. Tuy nhin phng th nghim phi c th chng t c rng nhng phng php l ng tin cy. b) Nhng phng php ny phi: o c ph duyt y . o Phi ghi thnh vn bno Phi c mt h thng thng xuyn xem xt s ph hp k thut

ca phng php. C th duyt phng php theo: o Cc phng php khc c xy dng o Dng cc cht chun c chng nhn v / hoc o Thng qua so snh lin phng Nu dng phng php th nhanh o Phng th nghim phi ph duyt phng php theo phng php th tiu chun (v lu tr vic ghi chp ph duyt)o Phng th nghim phi m bo kh nng s dng phng php

khng nh trong bt c tnh hung c bt ng.o Hng dn th nhanh phi c cp nht v lu gi trong s tay phng

php th. Cc phng php th theo dng ny c th phn phi cho cc nhn vin phng th nghim bng cc hnh thc; t hng dn hoc th hng dn phng php hoc tuyn tp phng php ghp cng s tay hng dn. D dng no, phi bo m:

72

o Bo v s tay hoc cc t ri phng php khng b h hng trong s dng. o Phn pht n tay nhn vin thc hin php th o Bo m rng chng s khng c bt c ai khng c trch nhim sa i. o Loi b cc phng php ht hiu lc khi s tay.

7.9. KIM SOT PHNG PHP TH qun l phng php th trong khp phng th nghim cn thit phi p dng cc nguyn tc ca vic kim sot ti liu c hiu lc. Vic kim sot p dng cho cc loi s tay phng php th, s tay hng dn v cc t hng dn cng vic v k c cc phng php th tiu chun. Cc phng th nghim c cng nhn phi thng xuyn sot xt cc phng php mnh bin son. i khi, cc phng php c thay th c th vn cn thch hp v nhiu l do nh vic thc hin hp ng, do vy cn lu gi nhng phng php nh th. a) Trch nhim Bin son Sa i y quyn Ban hnh b) Phn phi Lp danh sch ngi nhn Phn phi

c) Lp danh mc s tay K ra cc phng php Lp danh mc theo m s73

d) Kim sot e) Xem xt

Lp danh mc theo ni dung

Vic sao chp Cc ti liu loi b Cc sa i bt hp php Thanh tra nh k

Nhu cu thay i Vic duy tr Lu tr cc phng php b loi b

7.10. CC VT T KHC CN THIT CHO CC PHNG PHP TH Phng th nghim cn phi bin son th tc v:

Vic mua sm v nhng vt t/ vt liu

Vic nhn hng v c tnh ca chng c th nh hng

Lu kho n tin cy ca vic o/ kim

7.11. S DNG CC PHNG PHP TH Phi tun th n tng chi tit qui nh ca phng php th tiu chun, nhng phng php ni b v nhng phng php vit thnh vn bn. thc hin vic ny, nhn vin phng th nghim phi duy tr thng xuyn bng vic thng xuyn xem xt cc phng php th. i vi cc phng php khng thng xuyn s dng, phi c bin php duy tr nng lc ca phng th nghim bng cch tin hnh cc php th thc hnh c k hoch nh k mi mt qu hoc 6 thng hoc tin hnh hng lot t tp dt vi vic s dng cc mu chun hoc cht chun bit trc gi tr, trc khi th thc t. Phi ghi chp y kt qu cc t tp dt ny.

74

Trong trng hp yu cu tin hnh th phng th nghim khc ngoi s kim sot ca phng th nghim mnh v c s chp thun ca khch hng, phng th nghim phi ghi vo h s nhng khc bit v thng bo trn bo co th nghim 7.12. TM TT Cc phng php c th l cc tiu chun quc gia, quc t, cc ti liu c cng b hoc do phng th nghim bin son. Mi loi phng php c u v nhc im nht nh. Vic la chn loi phng php phi khng nh hng n phng th nghim v khch hng ca phng Phng php mi (v sa i so vi phng php hin c) cn phi c nh gi y trc khi p dng. Phng php phi c lp thnh vn bn Cc s tay tham kho v hng dn ring bit c th c dng. Vic kim sot ti liu tt phi c thc hin xuyn sut tt c cc phng php th.

75

QUN L CHT LNG PHNG TH NGHIM (QUALITY MANAGEMENT IN THE LABORATORY)

CHNG 8

CC KHI NIM V KHNG M BO O(Concepts of Uncertainty of Measurement)

Ch ny gip sinh vin: Thy tm quan trng ca khi nim khng m bo o vi hot ng th nghim. Hiu v phn bit cc thut ng lin quan n cht lng kt qu o v th nghim Hiu c cc bc tin hnh nh gi khng m bo

8.0. V SAO CN KHNG M BO O Cc yu cu v chun mc phng th nghim i vi Phng hiu chun Giy chng nhn hiu chun phi ch r tnh dn xut vi chun quc gia v phi cung cp cc kt qu v (cng vi) khng m bo (o): Phng th nghim v hiu chun: Mi giy chng nhn (hiu chun) hoc bin bn th nghim (bo co th nghim) phi gm t nht cc thng tin sau:76

a)

.. ..

l) Cng b v khng m bo c lng ca cc kt qu th nghim v hiu chun (nu thch hp) iu 13.2 TCVN 5958:1995/ISO/IEC Guide 25 Mt phng hiu chun hoc mt phng th nghim khi t tin hnh hiu chun php p dng mt qui trnh c lng khng m bo o i vi tt c cc php hiu chun v cc loi hiu chun. Cc phng th nghim phi xy dng v thc hin cc qui trnh c lng khng m bo o Phng th nghim phi c gng xc nh tt c cc thnh phn ca khng m bo v c lng thch hp m bo rng cc bo co th nghim khng gy n tng sai lch v khng m bo. Vic c lng phi da trn s hiu bit v cch thc tin hnh php th v trn phm vi o ng thi phi s dng cc d liu v kinh nghim ca khu trc Thc hin v cng b c lng khng m bo Bt buc i vi php hiu chun v phng hiu chun Cn i vi php th v phng th nghim

Nhm mc ch khng m bo ca kt qu hiu chun Cung cp d liu cho php hiu chun / o khc khng m bo ca kt qu o lng v th nghim Cung cp d liu cn thit cho kt qu v khong tin cy v v gii hn ti hn Phm vi p dng Cc php o, php hiu chun, php th nh gi cht lng v trnh kt qu o lng, th nghim.

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8.1. NHNG V D N GIN a) Bi ton qua Hai ngi mun qua sng trn con c ti trng ti a 140,0kg. cn thn, h tin hnh cn mnh bng mt chic cn c hiu chun v xc nhn vi khng m bo m rng mc cn n 100 kg l 0,2kg. Cc kt qu cn c l 72,3kg v 67,5kg. Bn c ngh rng hai ngi s yn tm xung ? gii p, chung ta cn tha nhn m khng cn hiu r v sao cch thc c lng v cch tnh khng m bo php cn m trnh by di y. Gi thit l cc gi tr thu c nu trn l trung bnh cng ca nhiu php cn do phn khng m bo ngu nhin l khng ng k. Ch cn l phn khng m bo do phng tin cn gy ra v d nhin nhng tc ng mi trng ln kt qu cn l khng ng k. Khi lng tng trung bnh l: 72,3 + 67,5 = 139,8kg Mi kt qu cn c khng m bo nh nhau l 0,2kg Tng hp li, khng m bo m rng l :Uexp = 0, 22 + 0, 22 = 0,28kg Chng ta nn hiu rng Uexp s cung cp khong tin cy cho kt qu 139,8kg nh l 0,28kg Ni cch khc, gi tr cn tng cng s dao ng t (139,8 0,28) = 139,52kg n (139,8 + 0,28) = 140,08kg By gi chng ta c th ni i iu v quyt nh ca ngi i . Xc sut trng ti 140,0 kg b vt qu l 95% Hai khch i chc chn khng dm mo him hy vng 5% khng b chm . b) Bi ton o din tch bc tng Mt b ni tr mun xc nh din tch bc tng phng tnh cng qut sn cn phng, B dng mt thc cun chiu di c chia vch n tng centimt o chiu ngang N v mt thanh g mng khong 2 mt o chiu cao C ri o li on g bng thc cun. Cc s o trung bnh nh sau:78

N = 398 cm, C1 = 200 cm v C2 = 143 cm Din tch bc tng A = 398 x (200 + 143) = 136.514 cm2 13,6514 m2 S o din tch c lm trn l 14,00 m2 v b ni tr ngh rng mnh cho s o din tch nh vy vi sai s khong (13,6514 14,00) / 13,6514 = 25% l chp nhn c. Cu hi t ra khng phi l vic lm trn c sai s bao nhiu m l thc cht php o phm sai s hay khng m bo l bao nhiu v c ngha g i vi vic lm trn s ca b ni tr. Chng ta cng phi t iu kin l cc yu t gy sai s khi o (nh nhit , lc cng thc, c sai do mt) l khng ng k v rng thc cun c hiu chun vi cc sai s nh hng mm (khng ng k). C cho rng bc tng c cc cnh hon ton vung gc vi nhau. Cc d liu v thc cun cung cp cho ta nhn nh rng. Mi php o cnh ngang N u m bo rng s o chc chn dao ng trong khong trn di 1 cm (hay 1cm) Mi php o chiu cao c khong dao ng ln hn v trc tin phi m thanh g vo tng, ri sau o thanh g (hay on g) trn thc cun. Nh vy ta c th ni chc rng C1 v C2 c khong dao ng trn di 2 cm (gp i so vi o chiu ngang) Theo l thuytv c lng khng m bo trong trng hp ny, ta c th p dng trng hp phn b xc sut kiu hnh ch nht v khng m bo s l: UN = 1/ 3 = 0,58 cm hay 0,58/398 = 0,21%

UC1 = UC2 = 2/ 3 = 1,15cm Nu tng hp cc thnh phn khng m bo chiu cao vi nhau, chng ta c: UC =(1,152 + 1,152 ) = 1,62 cm hay 1,62/343 = 0,47%

Tng hp t cc thnh phn khng m bo ca php o chiu cao v php o chiu ngang, chng ta c khng m bo din tch tnh theo phn trm l:79

UA/A = (0,212 + 0,472 ) = 0,51% Nu an ton, chng ta cn nhn khng m bo va tnh c vi mt h s m rng l 2, by gi chng ta c khng m bo m rng l 1,02 1,0% Nh vy, vic b ni tr lm trn s o din tch l 14m 2 thc ra phm phi mt sai s 2,5% l cao hn ng k so vi khong tin cy l 1% din tch. c) Nhng iu nhn xt c lng khng m bo, chng ta cn d liu trc , hoc do php

hiu chun cung cp nh v d a), hoc chng ta phi t tm (hoc c lng) nh v d b). ngha ca v d a) l: vi khng m bo c lng c, chng ta mi c kt lun xc ng v kt qu o/ th, tc chng ta s bit c cht lng ca kt qu v t mi a ra c kt lun th d nh c vt hay khng vt gii hn cho php. iu ny thng xy ra trong th nghim v nh gi cht lng sn phm, hng ha. ngha ca v d b) l: nu khng lm trn, ngi thc hin php o c th

din t kt qu cng vi khng m bo, v ngi s dng kt qa s nhn bit c s s dng chng nh th no, th d c th lm trn s c ngha khng? Trong trng hp ny, kt qu o nn cng b nh sau: Din tch bc tng A = 13,65m2 0,14m2 c 2 v d chng ta u n gin ha n mc khng tnh n cc thnh phn nh hng khc, nhng iu m sau ny chng ta khng th b qua. 8.2. THUT NG LIN QUAN KHI NIM KHNG M BO V c nhiu ti liu v nhiu cch nhn nhn khc nhau v cc thut ng v khi nim lin quan n o lng, cn thit phi thng nht v hiu chnh xc cc thut ng v khi nim, nu mun tip cn ng n khi nim khng m bo o. Ti liu trch dn sau y c cc t chc quc t bin son, gii thiu, nhiu quc gia c nn o lng pht trin nh M, Anh quc, c tha nhn v p dng. [1] International Vocabulary of Basic and General Terms in Metrology, gi tt l VIM80

[2] Guide to Expression of Unacertainty in Measurement gi tt l Guide, k hiu G. [3] TCVN 6165:1996 VIM:1993 o lng Thut ng chung v c bn hiu v quan trng l phn bit cc khi nim l vic kh. Nhng iu gii thch sau y gip chng ta t nhiu theo hng . GI TR THC (CA I LNG ) (true value) Gi tr ph hp vi nh ngha ca i lng ring bit. Ch : Gi tr ny c th xc nh c bng php o hon ho. V bn cht khng th xc nh c gi tr thc. GI TR THC QUI C (Conventional true value) Gi tr qui cho mt i lng ring bit v c chp nhn, i khi bng tha c, c` khng m bo ph hp vi mc ch Ch : y l gi tr gn ng vi gi tr n mc ta c th b qua s chnh lch gia chng vi nhau. Thng thng ngi ta ch dng gi tr thay cho gi tr thc hay gi tr thc qui c I LNG O (Measurand) i lng ring bit c o Th d: p sut hi nc ca mt mu nc 20oC Nh vy phi nu ra cc c im k thut ca i lng o. I LNG NH HNG (Influence quantities) i lng khng phi l i lng o nhng nh hng n kt qu o. Th d: nhit ca mt thc o chiu di; nng bilirubin trong php o nng haemoglobin ca mt mu huyt tng ngi. KT QU (CA) PHP O (Result of a measurement) Gi tr qui cho i lng o nhn c t php o.

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Ch : ngi ta cn phn bit gia kt qu o cha c hiu chnh v kt qu o c hiu chnh v gi tr trung bnh. Phi trnh by y cng vi cc thng tin v khng m bo ca php o. S (H S) HIU CHNH (Correction, Correction factor) Gi tr c cng vo (nhn vi) kt qu o cha c hiu chnh. Ch : s hiu chnh bng gi tr m ca sai s CHNH XC CA PHP O (accuracy of measurement) Mc gn nhau ca gia kt qu o v gi tr thc ca i lng o. Ch : chnh xc l mt khi nim nh tnh. Phi phn bit v trnh dng tp trung thay cho chnh xc chnh xc ca php o khc vi chnh xc ca phng tin o/dng c o. LP LI (CA KT QU O) (repeatability) Mc gn nhau gia kt qu cc php o lin tip cng mt i lng o trong nhng iu kin nh nhau. iu kin nh nhau gi l iu kin lp li, bao gm cng mt th tc o, cng ngi quan st, cng phng tin o, cng a im o, cng u kin mi trng v xy ra trong thi gian ngn. TI LP (CA KT QU O) (reproducibility) Thng s gn vi kt qu ca php o, c trng cho s phn tn cc gi tr c coi l hp l ca i lng o. Ch : khng m bo s khng c ngha nu ng ring mt mnh. Khi nim v nh ngha cng nh phng php xc nh n, din t trong kt qu php o rt phc tp v c nhiu thay i theo thi gian. p dng iu ny, cn phi nghin cu v thc hnh nhiu, ph thuc vo loi hnh hot ng th nghim (o lng hoc hiu chnh hoc th nghim), vo lnh vc th nghim c th (c, in, ha, xy dng, sinh hc)82

SAI S CA PHP O (error of measurement) Kt qu ca php o tr i gi tr (thc) ca i lng o. Ch : ngi ta dng gi tr thc qui c thay cho gi tr thc trong khi tnh sai s. Sai s l mt khi nim nh lng. N ch ni ln tnh cht ca mt kt qu o, trong khi khng m bo o ch trng n nhiu kt qu o (loi kt qu o) Mc d khng th bit c gi tr nhng c th c lng c khng m bo o. Nu so snh bng phng tin o vi chun m khng m bo ca chun v ca qui trnh so snh l khng ng k so vi khng m bo do thao tc o gy nn, ta c th xem php so snh l cch thc xc nh sai s ca phng tin o. iu ny rt thng thng trong vic hiu chun v kim nh phng tin o. Chng ta cn rt nhiu thut ng lin quan n khng m bo o m ti liu ny khng gii thiu su hn, m ch nu ra phn bit: Cn phn bit cc loi sai s ca php o. Sai s tuyt i sai s tng i Sai s ngu nhin sai s h thng i vi phng tin o cn phn bit cc thut ng Sai s - cp chnh xc

Sai s ca phng tin o - chnh xc ca phng tin o Sai s c bn Sai s ch th Sai s 8.3. CN LM R THM Cc thut ng chnh xc (CC-acuracy), lp li (repeatability-LL), ti lp (reproducibility-TL), s bin i (variability) v khng m bo (uncertainty-KB) l cc th d i din cc khi nim nh tnh v php o, do hy cn thn khi s dng chng.83

- sai s ng - sai s im 0 - ng (khng c sai s h thng)

Do , hy trnh dng chng nh nhng t ng ngha hoc dng m ch cc c lng nh lng ca php o. Th d: Cu chnh xc ca kt qu o din t di dng lch chun thu c trong iu kin lp li (nh nhau) l 2mA l chp nhn c. Nhng ni chnh xc ca kt qu o l 2mA l khng th chp nhn c. Quan h gia sai s v khng m bo cn c hiu r, t s c s phn bit v nh lng khi biu din kt qu o. Sai s c nh ngha l hiu s gia mt kt qu ring l v gi tr thc ca php o. Do , sai s l mt gi tr n l. V nguyn tc, phn h thng ca mt sai s c th c hiu chnh nu nh mi ngun gc gy nn sai s u c bit. mc d phn ngu nhin ca sai s (theo nh ngha) thay i t ln xc nh ny n ln xc nh k tip. Trong iu kin cho php v cn thit thao tc vin th nghim phi tin hnh hiu chnh bng cch cng vo kt qu o s hiu chnh *(hoc nhn vi h s hiu chnh). Tuy nhin, v s (h s) hiu chnh cng ch l s xp x nn sau khi hiu chnh, kt qu o vn cn d lng ca sai s (h thng). D lng ny s tham gia to ra khng m bo, gi l khng m bo hiu chnh. Mt khc, khng m bo c dng ca mt khong, v nu c c lng cho mt phng php o v mt i lng do th c th p dng cho mi php o nh m t. Khng th hiu chnh mt thnh phn no ca khng m bo. S khc bit gia sai s v khng m bo ca kt qu o cn th hin ch l kt qu ca mt php o sau khi hiu chnh c th may mn l rt gn vi gi tr (thc) ca i lng o, v do sai s c b qua. Tuy nhin khng m bo c th vn cn rt ln, n gin bi v ngi o khng bit chc rng kt qu gn vi gi tr thc n mc no. khng m bo ca kt qu ca mt php o khng bao gi c xem nh i din cho chnh sai s cng nh sai s c gi li sau khi hiu chnh. 8.4. S LC V CCH C LNG KHNG M BO Phn loi thnh phn khng m bo

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iu c bn khc vi l thuyt trc y (trc khi hng dn v din t khng m bo ban hnh), t nm 1995 trong cc ti liu ngi ta yu cu phn bit gia cc kiu c lng khng m bo khc nhau. l: c lng loi A khng m bo Chng c nh gi bng cc phng php khc nh t d liu hiu chun ca chun, phng tin o; t cc i lng nh hng nh mi trng, thao tc Cc bc tin hnh c lng khng m bo Bc 1: lp m hnh ton a ra hoc c lng m hnh ton hc gia i lng u ra Y v n i lng u vo Xi. Bc 2: Thu nhn cc gi tr i lng u vo xi Xc nh gi tr c lng ca cc i lng u vo xi, bng cc php o (hoc lot o) hoc bng cch khc. Bc 3: Lp biu thc khng m bo Lit k tt c cc ngun v i lng nh hng trong qu trnh o v xc nh khng m bo do cc i lng ny gy ra ( khng m bo thnh phn) Bc 4: c lng khng m bo chun thnh phn Ln lt xc nh khng m bo chun loi A v loi B ca tt c cc thnh phn khng m bo. Cn p dng cc kin thc v tnh thng k, cc dng phn b xc sut, l thuyt v cc bc t do. Bc 5: Tnh khng m bo chun tng hp Uc Lin hp v ton hc cc thnh phn khng m bo trong c ch n h s trng lng (h s nhy cm) Bc 6: Tnh khng m bo m rng Uexp Xc nh h s bao qut (ph) t s bc t do hiu dng, xc sut tin cy v cc khng m bo thnh phn. Nhn h s bao qut vi khng m bo chun tng hp. Bc 7: Din t kt qu php o

85

Vit biu thc gm gi tr trung bnh hp l ca i lng u ra cng vi khng m bo m rng (c du ) v km theo s cng b v xc sut tin cy.

86

QUN L CHT LNG PHNG TH NGHIM (QUALITY MANAGEMENT IN THE LABORATORY)

CHNG 9

QUN L MU TH(Management of Test Items)

Chng ny s trnh by v qun l: - Ly mu - Nhn mu - Nhn dng v bo qun mu - Vn chuyn v kim sot - Thanh l mu9.0. TNG QUT Khi im ca tt c phng th ngghim l mu th, mu vt hoc mu in hnh do khch hng gi n phng th nghim hoc do phng th nghim t tin hnh thu thp. Qun l mu th l rt quan trng, n bao qut tt c cc giai on t lc ly mu, bo qun, vn chuyn, nhn dng, tip nhn ti phng th nghim, chia mu, son mu, kim tra bo qun trong kho v n khi thanh l. Tuy nhin, khng phi tt c iu nu trn u p dng cho tt c phng th nghim. 9.1. LY MU

87

a) Phm vi cng vic m phng th nghim lin quan c th khc nhau. Mt s phng th nghim khng c trch nhim ly mu, hoc ch mt phn, s khc li phi chu trch nhim hon ton v ly mu. Loi phng th nghim nu sau phi c cng nhn c hot ng ly mu v nhn vin phi c o to v gim st y .b) Cc phng th nghim c trch nhim ly mu phi c th tc bng vn bn qui

nh ly mu v da vo c s cc tiu chun quc gia hay quc t hin hnh. Phng php ly mu ni b phng th nghim phi c c s thng k vng vng v phi ph hp vi mc ch. Phi c dng c ly mu nh th tc qui nh v phi bo qun chu o v phi ph ho vi c kch v dung sai qui nh trong cc qui trnh ly mu lin quan.c) Phng th nghim c trch nhim ly mu phi thng bo vic s dng th tc ly

mu no trn bo co (kt qu) th nghim. iu ny ht sc quan trng khi mu i din cho l sn phm. d) Ni no phng th nghim khng c trch nhim ly mu m ngi ly mu khng c kh nng cung cp cc ti liu tng ng ch r mu c ly theo dng cc th tc tiu chun, th iu ny phi c nu trong bo co (kt qu) th nghim, th d vit mu c th nh c gi n. Tuy nhin phi tm cch lin kt li t ngi nhn mu.e) Nu ngi ly mu khng phi l nhn vin phng th nghim, m l khch hng

nh cung cp, nhn vin cng ty h phi c cung cp cc ti liu hng dn ly mu hoc cc thng tin cn thu thp cho mi loi mu. Trong nhiu trng hp ngi ly mu phi c dng c cha sch c dn nhn v ngi ly mu phi c tp hun v k thut ly mu thch hp v cc ti liu cn thit. 9.2. BO QUN V VN CHUYN MU a) Phng th nghim cn phi vit th tc qui nh v c phng tin thch hp trnh tnh trng lm thay i, nhim bn hoc h hi mu hiu chun hoc mu th nghim trong qu trnh vn chuyn, lu kho, bo qun, chun b mu, v tin hnh hiu chun hay th nghim. Phi km theo cc hng dn lin quan v mu th.

88

b) Nu mu hiu chun hoc mu th cn bo qun trong iu kin mi trng c bit, cn phi duy tr iu kin, theo di v ghi chp khi cn thit c) Ch tun th cc qui nh ca nh nc v vn chuyn hng ha i vi mu cn vn chuyn bi cc phng tin vn ti cng cng, c bit ch trng qui nh vn ti hng khng (IATA) 9.3. NHN DNG MU a) Phng th nghim cn c h thng vn bn qui nh cch ghi du v k hiu thng nht v khng d b mt (xa, m, rt) gip nhn dng mu v truy xut h s.b) Cn phi lm nu mt mu th khng c dn nhn hoc dn nhn khng ng

cch: Loi b chng? Yu cu cung cp mu khc? Yu cu ngi ly mu cung cp thng tin? Ghi iu ny trong bo co (kt qu) th? ISO/IEC Guide 25:1990 yu cu, phi tham kho kin khch hng nu thy ng vc v nhn dng mu hoc s ph hp vi th nghim. kin ca khch hng phi c ghi li trong h s mu hay bo co th nghim. Nu bn c yu cu th mu m mu li yu cu p dng phng php th cho ring n, th phi ch iu ny ghi trn bo co th nghim v c h s th nghim. 9.4. NHN, KIM TRA V THANH L a) Tt c cc phng th nghim phi c th tc bng vn bn v: Nhn mu th Ghi s sch nhn mu Bo qun mu Lu mu Thanh l mu89

S tay cht lng phng th nghim phi ch r th tc qun l mu t lc nhn mu cho n lc thanh l mu Phi qui nh r iu kin nhn mu b) Khi nhn mu, phi ghi vo s nhn mu ca phng th nghim, mu s c th c nhiu hnh thc khc nhau. (1) Cn phi ghi chp g Tn ca khch hng? Tn mu ca khch hng? Yu cu th ca khch hng? Ngy v gi nhn mu? Tnh trng mu (bt thng, khc vi yu cu tiu chun) M ha mu ca phng th nghim? M t mu? (2) Hnh thc s ghi chp C s d liu my tnh? S nht k nhn mu? Mu giy c km theo mu? Mu giy yu cu th ca khch hng? Phiu xut xng (KCS)? (3) C cn phi cho s phng th nghim

Phng th nghim a chc nng (b phn) Khch hng a dng c th c nhiu tn Cc l khng c tn Khch hng mun bo mt Nhm thng k ti chnh90

C s d liu my tnh D qun l v tra cu khi kim tra Cc mu c bit trong kim tra cht lng ca PTN

(4) C cn t Yu cu th nghim v Theo di tin trnh Phng th nghim c nhiu b phn Cn c s chi tit ha yu cu Theo di tin trnh th nghim

c) Nu phi nhn mt mu khng ng tin cy m khng c kh nng loi b n, phng th nghim phi vit r rng iu thiu st mnh nhn thy trn h s th nghim v bo co th nghim d) Ni no mu hiu chun hoc mu th nghim (nguyn mu hay ch mt phn) cn c bo qun an ton (th d v l do cc s liu bo co cn gi kn hay cn phi th li sau mt thi gian ch i), phng th nghim nht thit phi bo m vic lu gi ni an ton theo yu cu. e) Mt s mu th v cht ph thi ca phng th nghim cn thanh l (c bit trong th nghim ha, sinh hc v y t) phi c thc hin theo cc qui nh ca nh nc. 9.5. TM TT Mt trong nhng nguyn nhn dn n cc kt qu thiu chnh xc l vic qun l mu th. V vy, cn ch nhng iu quan trng sau: Hun luyn nhn vin k cng trong khu qun l mu Phi c cc th tc v cc bc ly mu, chuyn gia mu thc hin bn trong v bn ngoi phng th nghim Phi ghi chp ng v y v cc kha cnh ca vic qun l mu, c bit l vic dn nhn trn mu th.

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QUN L CHT LNG PHNG TH NGHM (QUALITY MANAGEMENT IN THE LABORATORY)

CHNG 10

GHI CHP & BO CO(Records and Reports)

Chng ny s: - Trnh by h thng ghi chp v bo co - Nhng iu nn trnh trong ghi chp v bo co10.0. CC H THNG GHI CHP V BO CO Phng th nghim va l ni s dng va l ni cung cp thng tin. Vic ghi chp v x l cc s liu th nghim v ban hnh phiu kt qu th nghim khng phi l cc hot ng h tr (ph) m chng l nhng b phn ch yu ca ton b qu trnh th nghim. Vic ghi chp cung cp cc bng chng xc thc v cch thc hin th nghim, v thit yu cho vic gii quyt ng n cc vn th nghim, tranh chp gia cc phng th nghim hoc khiu ni ca khch hng. ng tic l vic ghi chp ng s liu v bo co kt qu cn b nh gi thp tm quan trng v hu qu l cc sai li v thiu st trong h thng ghi chp l mt trong ba l do chnh gy tranh chp gia cc phng th nghim v khiu ni ca khch hng. 10.1. C TRNG CA H THNG GHI CHP

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Mi phng th nghim phi xy dng v duy tr mt h thng ghi chp ng c cc chc nng cc iu kin v nhu cu ca mnh. Cho d h thng ghi chp s dng bt c biu mu no, phi p ng c cc yu cu sau y:

Kh nng truy cp ngun gc t lc nhn mu ban u, trong sut cc hot ng th nghim, n khi pht hnh bo co v lu tr bn sao ca bo co.

Tnh y cung cp s m t r rng tng hot ng th nghim v kt qu ca chng.

Tnh ng n cung cp c cu pht hin v sa cha cc sai li trong khi ghi chp, tnh ton v ghi chp s liu.

S r rng nhm gip cho ngi hiu bit cng vic c th nhn ra v nhn dng v hiu c nhng iu ghi chp.

Lu tr tt c cc s liu th, cc quan st th nghim v cc bn sao ca bo co phi c gn gi mt cch an ton sao cho c th thu hi d dng, an ton v bo mt cho khch hng, tr phi c cc yu cu khc v mt php lut.

Tnh n gin ng lm phc tp hn mc cn thit p ng cc yu cu ca phng th nghim v ca khch hng.

10.2. GHI CHP TH NGHIM TRONG PHNG TH NGHIM Tt c cc ghi chp th nghim phi r rng d c v chi tit cho php mt ngi khc