An Introduction to Quality Assurance in Analytical Science

1. An Introduction to Quality Assurance in Analytical Science Dr Irene Mueller-Harvey Mr Richard Baker Mr Brian Woodget

2. Part 3 - Quality systems Contents: • Introduction to quality systems (slides 3,4) • QA and QC systems (slides 5-9) • Measurement traceability (slides 10,11) • Reference materials and check samples (slide 12) • Keeping track of samples (slide 13) • Quality manual (slides 14-17) • Quality system filing (slide 18) The presentation contains some animation which will be activated automatically (no more than a 2 second delay), by mouse click or by use of the ‘page down’ key on your keyboard.

3. Without a Laboratory Quality System - too many mistakes can make analysis very costly; due to expenses caused by wrong decisions, or costs of analysis • repeating analysis of samples • investigation of problems • revision of procedures • loss of good reputation

4. Prevention is Better than cure! ‘It costs less to prevent a problem than it does to correct it’ A formal quality system in the laboratory should prevent mistakes by means of: • quality assurance measures • quality control of the analytical results • thorough documentation of the system • efficient maintenance of records • regular audits of all aspects of the system

5. QA and QC systems Quality Control: planned activities designed to provide a quality product. Quality Assurance: planned activities designed to ensure that the quality control activities are being properly implemented. (As defined by the Association of Official Analytical Chemists)

6. QA Systems Quality Assurance measures apply to the laboratory analytical work overall, which includes; • identifying the person having the overall • responsibility for quality • having laboratory equipment calibrated • to recognised standards • using reference materials • joining proficiency testing schemes with • other laboratories doing similar tests

7. QC systems Quality control measures apply to each analytical test in the laboratory by use of: • reagent blanks; • verified standard solutions; • check samples (from both within the lab and from outside); Control chart • blind samples • replicate analyses; • and control charts

8. Quality systems - control charts A control chart is a means of ensuring that the method remains in ‘control’ - continues to perform in accordance with expectations. This usually means that results from analysing standards fall within + 2 standard deviations of the accepted value (within the blue lines on the chart). Any results appearing outside the red lines (+ 3 standard deviations) indicate that the method is not longer in control and requires investigation.

9. Use of QC Samples Step change Regular analysis of a single control sample will identify a system in or out of control conditions Bias Target value Drift In control Daily QC data

10. Measurement traceability In an absolute sense, the ‘true’ value can be defined only as being that value directly traceable to the base system of measurement (SI) or their derivatives - ie: to national or international standards via an unbroken chain of comparisons SI unit Transfers accuracy Provides traceability Certified reference material Laboratory working standard Analytical method

11. Measurement traceability (2) The Sample Analysed by The SI units: Kg, Metre, Mole Secondary method: e.g. lab. method Calibrated by Primary methods (often gravimetric) e.g. AOAC, EPA Calibration Standards Method routinely checked by Certified by analysis Secondary RMs In-house QC materials (fairly cheap, larger amounts, matrix matched, short life) Certified Reference Materials (CRMs - expensive, small amounts, best accuracy, long life) Periodically checked

12. Reference materials & check samples SAMPLES SUPPLIED FOR PROFICIENCY TESTING INTERNAL QC SAMPLES Internal QC samples are prepared and quantity values of target components are checked against CRMs An accredited laboratory has to prove its performance by routinely analysing samples supplied by an independent laboratory CERTIFIED REFERENCE MATERIALS (CRMs)

13. Keeping track of the samples Lab. No. F7-002 • Sample registration gives each sample a unique lab number. • The sample register records all the information about the sample. • Just like a sample’s passport, you should not confuse any sample with any other. • The history of the sample should be traceable throughout. Sample integrity Samples recorded on receipt

14. QualityManual Laboratory Quality System Quality Manual Admin 1.5.1. Page 1 of 1 Amiable Laboratory Issue No. Issue Date Title of Section Title Page Issued by QUALITY MANUAL for Amiable Laboratory Benevolent Department Well-intentioned Organisation Usual Location A quality manual defines the quality system under which the laboratory operates This Manual is issued under the authority of Issue Date ............................................................ Issue No. 3 A Person Copy No. Holder Head of Laboratory Quality Manual - cover page

15. QualityManual - contents (1)

16. QualityManual - contents (2) -

17. QualityManual - contents (3)

18. 1. Admin Audit reports 4. Procedures System reviews Blank forms List of General Procedures Memos 4.01 Calibration records Notices 4.02 Complaints and anomalies Quality Manual 4.03 Equipment records Record of anomalies 4.04 Method validation Preventive actions 4.05 Quality audits 1.2.1.(index) 4.06 Quality control records General contract 4.07 Reference standards 5. Quality Control 2. Validation 4.08 Result acceptability 5.01 Fibre analysis Fibre 5.02 Milk analysis 4.09 Result reporting 5.03 Feed analysis Milk 4.10 Result uncertainties 5.04 N by combustion Proficiency test 4.11 Sample disposal 5.05 Q.C. limits 4.12 Sample reception 3. Equipment 5.06 Test reports & log 4.13 Sample registration 3.01 Equip records 6. Staff Records 4.14 Staff records 3.02 Operating procedures Job descriptions 4.15 System reviews 3.2.1. balance 7. Standard Methods 4.16 Training and competence 3.2.2. ovens ADF 4.17 Recording and storing data 3.2.3. muffles Dry matters 4.18 Document control 3.2.4. thermometers Fat, protein & lactose in milk 3.2.5. pH meters NDF Quality system files