QAQC

Question 0

Sample QA Responsibilities include:

Answer 0

 Reporting results in a timely manner.
 Reporting results to the appropriate individual.
 Making sure that the laboratory is functioning in the most efficient way.
 Continuing education programmes for laboratory workers.
 Evaluating laboratory personnel to identify areas for improvement.
 Using the most reliable tests.
 Verifying final reports.

Question 1

Quality Assurance is defined as

Answer 1

a system of monitoring, evaluating and documenting that lends proof of analysis.

Question 2

Quality Control describes….

Answer 2

the day to day monitoring of the accuracy and precision at the laboratory level.

Question 3

Sample QC Responsibilities include….

Answer 3

 Standard operating procedures (SOPs). 
 Blanks, duplicates and control samples. 
 Calibration standards.
 Matrix spikes.
 Control charts.

Question 4

What is Quality Assessment

Answer 4

a challenge to the effectiveness of the QA and QC programs. It is a measure of the quality assurance and quality control practices that are in place.

Question 5

Quality Assessment Activities include

Answer 5

Blinds, round robins.
Performance evaluation samples.
Certified reference materials.
Audits.

Question 6

What are three blanks used in the field

Answer 6

Equipment (Rinsate) Blanks
o Contamination from sampling equipment.
Field Blanks
o Contamination from the sampling environment.
Trip Blanks
o Contamination from artifacts introduced by cross-contamination.

Question 7

List two background samples and explain them

Answer 7

1. Control Samples
   o Samples from a control site must be collected from a location that
   is upwind of the suspect site. In that respect, it must also be up- gradient of the suspect site with respect to groundwater and surface water flow direction. Travel between the control site and the contaminated site should be minimized to avoid problems associated with transport by vehicles.
2. Field Spike Samples
   o When performing a field spike, a known amount of analyte is
   added to the sample during collection. A field spike identifies any field, transport, matrix effects or interferences that may be present. It is particularly useful when background samples are not attainable.

Question 8

define bias

Answer 8

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

Question 9

What are the two types of Errors and describe them

Answer 9

o Systematic (determinant)
 Systematic errors are reproducible inaccuracies that are consistently in the same direction. This type of error affects the data average.

o Random (indeterminate)
 Random errors are statistical fluctuations (in either
direction) in the measured data. They add variability to the data but do not affect average.

Question 10

The quality control practices used to minimize errors include….

Answer 10

Control samples 
o Spikes
o Blanks
Documentation
o Record keeping o Indelible ink
-Training
-Equipment maintenance (preventative maintenance)
-Equipment calibration

Question 11

What are three principles that govern the practices of document control:

Answer 11

1. Permanence
   o Use of indelible ink; correction drawn out with a single line;
   initialed and dated.
2. Attributable
   o All records are signed and dated.
3. Secure
   o Proof that samples and results were not altered, destroyed or tampered with.