QA - NPAP

NPAP = National Performance Audit Program

40 CFR Part 58 Appendix A section 2.4 describes requirements for the National Performance Evaluation Programs including a description of the National Performance Audit Program. The NPAP assessment is an independent audit of the PQAO’s gaseous monitors, performed by USEPA. In a few cases, the authority to perform the NPAP audits has been delegated to a “self-implementing” agency (a State Agency). In this case, the State will be allowed to enter annual performance evaluations representing NPAP audits. Otherwise, the PQAO cannot be the NPAP auditing agency.

20% of the PQAO’s monitors must be audited each year, resulting in complete network coverage every 5 years. Mobile auditing labs or equipment travel to the monitor sites and perform the assessment.

The audit is performed by challenging the gaseous monitors with known, independent standards. These standards are either introduced at the inlet of the sampling probe (referred to as through the probe), or directly into the monitor (referred to as back of analyzer) when it is difficult to introduce the standard at the inlet of the probe due to logistical concerns. Depending on how the standard is introduced to the monitor, the audit is referred to as either an NPAP - TTP, or NPAP - BOA

The standards used for the assessment are commercially supplied standards that comply with NIST standards, and are used when conducting audits for the following monitors:

  • O3 (using an ozone generator)

  • NO2

  • 3 channels used for NO2; 2 are physical for measuring NOx and NO, the 3rd is a difference of the others.

  • CO

  • SO2

  • Multiblend Audits which include CO/NO/SO2 and O3 generator

Audits are conducted at various concentration levels. These levels are achieved by diluting the multiblend cylinder gases to the desired concentration levels. The diluted gas is analyzed with a certified USEPA CO analyzer to check that the correct CO concentration is achieved. The other gas concentrations are then assumed to be proportionally correct. The S/L/T monitors are then audited using the diluted standard gas at three or more concentration levels.

Format

QA - National Performance Audit Program transaction format

Seq.

Name

Description

Formatting Rules

Required

Key

1

Transaction Type

Quality Assurance transaction identifier.

Must = QA

Always

2

Action Indicator

Indicator for Insert, Update, or Delete action.

Must = I, U, or D

Always

3

Assessment Type

Indicates the specific QA assessment associated with the transaction.

Must = NPAP

Always

Y

4

Performing Agency

Agency Code of organization performing assessment.

Must exist in AGENCIES reference table.

Optional; defaults to user agency

5

State Code / Tribal Indicator

The FIPS state code of the monitor, or “TT” to indicate that the next field on the transaction is a Tribal code.

Must exist in STATES Reference Table or be ‘TT’ for Tribal Site

Always

Y

6

County Code / Tribal Code

The FIPS County Code of the site. If the previous field on the transaction contains “TT”, then the Tribal Code of the site.

Must exist in COUNTIES (for state) or TRIBAL_AREAS Reference table

Always

Y

7

Site Number

Four digit number to uniquely identify site in county and/or tribe.

Must exist in SITES table with {State Code, county Code} or Tribal Code

Always

Y

8

Parameter Code

The AQS parameter code assigned to the monitor in AQS.

Must exist in PARAMETERS reference table.

Always

Y

9

POC

Parameter Occurrence Code: One or two digit number identifying a specific monitor for a parameter at the site.

Must exist in MONITOR table for non-Insert actions.

Always

Y

10

Assessment Date

Date that the assessment was performed

YYYYMMDD.

Always

Y

11

Assessment Number

A unique number associated with an assessment performed at a site on a given day. Value should be “1” unless additional same assessments are performed.

Integer.

Always

Y

12

NPAP Type

Indicates where the PEP monitor is operated by the Audit Agency or by the Monitoring Agency.

Must = TTP or BOA

Insert

13

Monitor Method Code

The sampling methodology of the monitor being assessed.

Must exist in SAMPLING METHODOLOGIES reference table.

Insert

14

Assessment Method Code

For parameters other than Ozone, this is the method code of the CO monitor used to determine check gas dilution.

Must exist in SAMPLING METHODOLOGIES reference table.

Insert unless ozone

15

Reported Unit

Units associated with the assessment concentrations (Monitor Concentration and Check Standard Concentration).

Must exist in UNITS reference table, and unit code must be for Concentration units type.

Unless Delete

16

Level 1 Monitor Concentration

The concentration value provided by the monitor being assessed at level 1.

Decimal.

Insert

17

Level 1 Assessment Concentration

The value of the known gas standard concentration in Audit Level 1.

Decimal.

Insert

18

Level 2 Monitor Concentration

The concentration value provided by the monitor being assessed at level 2.

Decimal.

Insert

19

Level 2 Assessment Concentration

The value of the known gas standard concentration in Audit Level 2.

Decimal.

Insert

20

Level 3 Monitor Concentration

The concentration value provided by the monitor being assessed at level 3.

Decimal.

Insert

21

Level 3 Assessment Concentration

The value of the known gas standard concentration in Audit Level 3.

Decimal.

Insert

22

Level 4 Monitor Concentration

The concentration value provided by the monitor being assessed at level 4.

Decimal.

Insert

23

Level 4 Assessment Concentration

The value of the known gas standard concentration in Audit Level 4.

Decimal.

Insert

24

Level 5 Monitor Concentration

The concentration value provided by the monitor being assessed at level 5.

Decimal.

Insert

25

Level 5 Assessment Concentration

The value of the known gas standard concentration in Audit Level 5.

Decimal.

Insert

26

Level 6 Monitor Concentration

The concentration value provided by the monitor being assessed at level 6.

Decimal.

Insert

27

Level 6 Assessment Concentration

The value of the known gas standard concentration in Audit Level 6.

Decimal.

Insert

28

Level 7 Monitor Concentration

The concentration value provided by the monitor being assessed at level 7.

Decimal.

Insert

29

Level 7 Assessment Concentration

The value of the known gas standard concentration in Audit Level 7.

Decimal.

Insert

30

Level 8 Monitor Concentration

The concentration value provided by the monitor being assessed at level 8.

Decimal.

Insert

31

Level 8 Assessment Concentration

The value of the known gas standard concentration in Audit Level 8.

Decimal.

Insert

32

Level 9 Monitor Concentration

The concentration value provided by the monitor being assessed at level 9.

Decimal.

Insert

33

Level 9 Assessment Concentration

The value of the known gas standard concentration in Audit Level 9.

Decimal.

Insert

34

Level 10 Monitor Concentration

The concentration value provided by the monitor being assessed at level 10.

Decimal.

Insert

35

Level 10 Assessment Concentration

The value of the known gas standard concentration in Audit Level 10.

Decimal.

Insert