Analytical gases must meet the accuracy and purity specifications of this section, unless you can show that other specifications would not affect your ability to show that you comply with all applicable emission standards.
Table 1 to Paragraph (a)(1)(ii) of § 1065.750 -General Specifications for Purified Gasesa
Constituent | Purified Air | Purified N2 |
THC (C1-equivalent) | [LESS THAN EQUAL TO] 0.05 [MICRO]mol/mol | [LESS THAN EQUAL TO] 0.05 [MICRO]mol/mol |
CO | [LESS THAN EQUAL TO] 1 [MICRO]mol/mol | [LESS THAN EQUAL TO] 1 [MICRO]mol/mol |
CO2 | [LESS THAN EQUAL TO] 10 [MICRO]mol/mol | [LESS THAN EQUAL TO] 10 [MICRO]mol/mol |
O2 | 0.205 to 0.215 mol/mol | [LESS THAN EQUAL TO] 2 [MICRO]mol/mol |
NOX | [LESS THAN EQUAL TO] 0.02 [MICRO]mol/mol | [LESS THAN EQUAL TO] 0.02 [MICRO]mol/mol |
N2Ob | [LESS THAN EQUAL TO] 0.02 [MICRO]mol/mol | [LESS THAN EQUAL TO] 0.02 [MICRO]mol/mol |
H2c | [LESS THAN EQUAL TO] 1 [MICRO]mol/mol | [LESS THAN EQUAL TO] 1 [MICRO]mol/mol |
NH3d | [LESS THAN EQUAL TO] 1 [MICRO]mol/mol | [LESS THAN EQUAL TO] 1 [MICRO]mol/mol |
H2Oe | [LESS THAN EQUAL TO] 5 [MICRO]mol/mol | [LESS THAN EQUAL TO] 5 [MICRO]mol/mol |
a We do not require these levels of purity to be NIST-traceable.
b The N2O limit applies only if the standard-setting part requires you to report N2O or certify to an N2O standard.
c The H2 limit only applies for testing with H2 fuel.
d The NH3 limit only applies for testing with NH3 fuel.
e The H2O limit only applies for water measurement according to § 1065.257.
Eq. 1065.750-1
Eq. 1065.750-2
Eq. 1065.750-3
Where:
Tdew = saturation temperature of water at measured conditions.
UTdew = expanded uncertainty (k = 2) of the measured saturation temperature of water at measured conditions.
pabs = wet static absolute pressure at the location of the dewpoint measurement.
UPabs = expanded uncertainty (k = 2) of the wet static absolute pressure at the location of the dewpoint measurement.
Example:
Tdew
UTdew
pabs
UPabs
Using Eq. 1065.645-1,
xH2O
Eq. 1065.750-4
Eq. 1065.750-5
Eq. 1065.750-6
Eq. 1065.750-7
Where:
ngas = molar flow of gas entering the humidity generator.
Ungas = expanded uncertainty (k=2) of the molar flow of gas entering the humidity generator.
nH2O = molar flow of H2O entering the humidity generator, mol/s.
UnH2O = expanded uncertainty (k=2) of the molar flow of H2O entering the humidity generator.
xH2O = amount of H2O in the calibration gas.
UXH2O = expanded uncertainty (k=2) of the amount of H2O in the generated calibration gas.
nH2O
Ungas = 0.000226137 mol/s
ngas = 0.0148680 mol/s
UnH2O = 0.0000207436 mol/s
40 C.F.R. §1065.750