Module 10

Question 1

Define QA

Answer 1

Quality assurance is a system of monitoring, evaluating and documenting that leads proof of analysis

Question 2

Sample QA responsibilities

Answer 2

• reporting in timely manner
• reporting results to the appropriate individual
• make sure lab if functioning efficiently
• continuing ed programs for lab workers
• evaluating lab personnel. Identify areas of improvement
• use reliable tests
• verify final reports

Question 3

Define qc

Answer 3

Quality control describes the day to day monitoring of the accuracy and precision at lab level

Question 4

Sample qc responsibilities

Answer 4

• standard operating procedures (sops)
• blanks, duplicates and control samples
• calibration stds
• matrix spikes
• control charts

Question 5

Define sops

Answer 5

Standard operating procedures

Question 6

Define Qassess

Answer 6

Quality assessment is a Challenge to the effectiveness of a QA and QC programs . Measure of the quality assurance and quality control practices that are in place

Question 7

Sample Qassess activities

Answer 7

• blinds, round robins
• performance evaluation samples
• certified reference materials
• audits

Question 8

What blanks used in the field

Answer 8

• equipment (rinsate) blanks
• field blanks
• trip blanks

Question 9

Explain rinsate blanks

Answer 9

Checks contamination of sampling equipment

Question 10

Explain field blanks

Answer 10

Checks contamination from the sampling equipment

Question 11

Explain trip blanks

Answer 11

Checks contamination from artifacts introduced by cross contamination

Question 12

2 types of background samples

Answer 12

1. control samples

2. Spike samples

Question 13

Explain control samples

Answer 13

Samples taken from control site must be collected (upwind of suspect site and up gradient with ground water)

Question 14

Explain spike samples

Answer 14

A known amount of analyte is added to the sample during collection. Identify any transport, field, matrix effects or interferences that may be present . (Useful if background samples aren’t available)

Question 15

Define accuracy

Answer 15

Accuracy is a measure of closeness to true value

Question 16

Define precision

Answer 16

Describes the overall uncertainty from

A random variation. It is a measure of the repeatability of an analysis

Question 17

Define bias

Answer 17

Bias is a directional error, expressed as either high or low. Bias refers to variation of data from theoretical value

Question 18

Define error

Answer 18

• systematic (determinant)
  - >systematic error are reproducible inaccuracies that are consistently in the same direction. This type of error effects the data average
• random (indeterminate)
  - > random errors are statistical fluctuations (in either direction) in the measure data . They add variability to the data but do not affect average

Question 19

3 sources of error

Answer 19

1. data phase
2. implementation
3. Lab analysis

Question 20

Quality control practices used to minimize errors

Answer 20

• control samples (spikes and blanks)
• documentation (record keeping and indelible ink)
• training
• equipment maintenance (preventative maintenance)
• equipment calibration

Question 21

Sam

Answer 21

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