Audit Results
In the Report of Analysis: Environmental Protection Agency Blind Audit 2013, the National Institute of Standards and Technology (NIST) analyzed 240 calibration gases between 2013 and 2015. The mixtures were tri-blends of carbon dioxide (CO2; range: 5% mol/mol – 20% mol/mol); nitric oxide (NO; range: 25 µmol/mol – 1000 µmol/mol (ppm) and total oxides of nitrogen, NOX, within 1% relative of NO) and sulfur dioxide (SO2; range : 50 µmol/mol – 1000 µmol/mol (ppm)).
The 2013 audit of EPA protocol gases found a 2.1% failure rate over all components analyzed, with 15% of the production sites failing at least one gaseous component. The Report of Analysis: Environmental Protection Agency Blind Audit 2013 was compiled by NIST and released on April 21, 2015.
2013 Results at a Glance
| Category | Amount |
|---|---|
| Number of Samples | 240 |
| Number of Failures | 5 |
| Passing Percent | 98% |
| Number of Production Sites | 20 |
| Number of Production Sites that Failed | 4 |
| Percent of Production Sites that Failed | 20% |
| Number of Participating Vendors | 11 |
| Number of Vendors that Failed | 4 |
| Percent of Vendors that Failed | 36% |