Quality assurance

Question 1

Define quality?

Answer 1

the totality of features and characteristics of a product or service that bear on its ability to satisfy stated or implied needs

Question 2

Define quality assurance?

Answer 2

all those planned and systematic actions necessary to provide adequate confidence that a product, process or service will satisfy given quality requirements

Question 3

Define quality control?

Answer 3

the operational techniques and activities that are used to fulfil requirements for quality

Question 4

What does quality control relate to?

Answer 4

Ensuring the quality of specific sample or batches

Question 5

What does quality control include?

Answer 5

• Analysis of reference materials
• Analysis of blind samples
• Use of quality control samples & control charts
• Analysis of blanks
• Analysis of spiked samples
• Inter-laboratory comparisons

Question 6

Define quality system?

Answer 6

the organisational structure, responsibilities, procedures and resources for implementing quality management

Question 7

Define quality management?

Answer 7

the aspects of the overall management function that determines and implements the quality policy

Question 8

Define quality policy?

Answer 8

the overall quality intentions and directions of an organisation as regards quality as formally expressed by the top management

Question 9

What are the parameters that need to be considered when selecting an analytical method to ensure quality?

Answer 9

• the level of accuracy and precision required;
• the sample type (what is the matrix?);
• the sample size (is a large quantity available?);
• the expected concentration of analyte;
• the likely interferences;
• the number and frequency of samples for analysis.

Question 10

Define method validation?

Answer 10

the process by which the performance of an analytical method is demonstrated to be fit-for-purpose

Question 11

Why is it important to use a standard measure wherever possible?

Answer 11

this will save a considerable amount of development time

Question 12

What does the selectivity of a method refer to?

Answer 12

the ability of a method to determine particular analyte(s) in a complex mixture without interference from the other components in the matrix

Question 13

How should the applicability of a method be studied?

Answer 13

using various samples, ranging from pure measurement standards to mixtures with complex matrices.In each case the recovery of the analyte(s) of interest should be determined and the influences of suspected interferences duly stated

Question 14

How can you tell if there is an interference that may be present in the sample matrix?

Answer 14

If the sensitivity (slope) of the standard addition graph is different from that obtained by normal calibration

Question 15

How is the linearity for quantitive methods determined?

Answer 15

by the measurement of samples with analyte concentrations spanning the claimed range of the method

Question 16

Define traceability?

Answer 16

the property of the result of a measurement or the value of a standard whereby it can be related to stated references, usually national or international standards, through an unbroken chain of comparisons all having stated uncertainties

Question 17

What is the SI?

Answer 17

the internationally recognised system of units

Question 18

Why is traceability important?

Answer 18

Because it ensures that measurements made in different labs or at different times are all still comparable

Question 19

What is an example of traceability and how does ti work?

Answer 19

The calibration of balances: The service engineer will use a standard weight to check the calibration of each balance. This standard weight will be certified in that its weight can be traced back to a comparison

Question 20

How does bias work?

Answer 20

is a measurement of the systematic error of that method. This can be tested by the use of reference materials

Question 21

What is precision?

Answer 21

Is a statement of the closeness of agreement between mutually independent test results and is usually stated in terms of standard deviation