8. QUALITY ASSURANCE AND QUALITY CONTROL

Quality Assurance/Quality Control (QAQC) procedures are required to ensure that the data collected meet standards of reliability and accuracy (see Section 5.1). Quality Control (QC) is defined as those operational procedures that will be routinely followed during the normal operation of the monitoring system to ensure that a measurement process is working properly. These procedures include periodic calibration of the instruments, site inspections, data screening, data validation, and preventive maintenance. The QC procedures should produce quantitative documentation to support claims of accuracy. Quality Assurance (QA) is defined as those procedures that will be performed on a more occasional basis to provide assurance that the measurement process is producing data that meets the data quality objectives (DQO). These procedures include routine evaluation of how the QC procedures are implemented (system audits) and assessments of instrument performance (performance audits).

The QAQC procedures should be documented in a Quality Assurance Project Plan (QAPP) and should include a "sign-off" by the appropriate project or organizational authority. The QAPP should include the following [63]:

1. Project description - how meteorology is to be used
2. Project organization - how data validity is supported
3. QA objective - how QA will document validity claims
4. Calibration method and frequency - for meteorology
5. Data flow - from samples to archived valid values
6. Validation and reporting methods - for meteorology
7. Audits - performance and system
8. Preventive maintenance
9. Procedures to implement QA objectives - details
10. Management support - corrective action and reports

It is important that the person providing the QA be independent of the organization responsible for the collection of the data and the maintenance of the measurement systems. Ideally, this person should be employed by an independent company. There should not be any lines of intimidation available to the operators which might be used to influence the QA audit report and actions. With identical goals of valid data, the QA person should encourage the operator to use the same methods the QA person uses (presumably these are the most comprehensive methods) when challenging the measurement system during a performance audit. When this is done, the QA task reduces to spot checks of performance and examination of records thus providing the best data with the best documentation at the least cost.

8. QUALITY ASSURANCE AND QUALITY CONTROL
8.1 Instrument Procurement 
     8.1.1 Wind Speed 
     8.1.2 Wind Direction  
     8.1.3 Temperature and Temperature Difference 
     8.1.4 Dew Point Temperature 
     8.1.5 Precipitation 
     8.1.6 Pressure 
     8.1.7 Radiation  
 8.2 Installation and Acceptance Testing
     8.2.1 Wind Speed 
     8.2.2 Wind Direction  
     8.2.3 Temperature and Temperature Difference 
     8.2.4 Dew Point Temperature 
     8.2.5 Precipitation 
     8.2.6 Pressure
     8.2.7 Radiation
  8.3 Routine Calibrations  
      8.3.1 Sensor Check  
      8.3.2 Signal Conditioner and Recorder Check  
     8.3.3 Calibration Data Logs 
     8.3.4 Calibration Report  
     8.3.5 Calibration Schedule/Frequency 
     8.3.6 Data Correction Based on Calibration Results  
  8.4 Audits 
     8.4.1 Audit Schedule and Frequency  
     8.4.2 Audit Procedure 
     8.4.3 Corrective Action and Reporting 
  8.5 Routine and Preventive Maintenance 
     8.5.1 Standard Operating Procedures  
     8.5.2 Preventive Maintenance  
 8.6 Data Validation and Reporting  
     8.6.1 Preparatory Steps 
     8.6.2 Levels of Validation  
     8.6.3 Validation Procedures  
     8.6.4 Schedule and Reporting
  8.7 Recommendations