## 3 Results
### Comparison of the Mitigation of Targeted Gases as a Function of UV Wavelength
#### 3.2.4 Greenhouse Gases  
Effects of UV Wavelength  
Significant mitigation was measured for CH\({}_{4}\), with the (185 + 254) nm lamps. However, other wavelength lamps did not show statistically significant reduction (Table 9). CO\({}_{2}\) concentrations increased for all UV wavelengths tested (Table S10) and were statistically significant for 185 + 254 nm and 367 nm (high UV dose). N\({}_{2}\)O was mitigated at statistically significant levels (from 8 to 25%) for all treatments except for the low 367 nm dose (Table 10). The highest percent reduction for CH\({}_{4}\) and N\({}_{2}\)O resulted from the 185 + 254 nm treatment. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & \multicolumn{4}{c}{**Percent Reduction (\(p\)-Value)**} \\ \cline{2-6}
**Targeted** & \multicolumn{2}{c}{**UV-C Dose, \(\mu\)/cm\({}^{2}\)**} & \multicolumn{2}{c}{**UV-A Dose**} \\  & \multicolumn{2}{c}{**(Light Intensity, \(\mu\)W/cm\({}^{2}\))**} & \multicolumn{2}{c}{**(Light Intensity, \(\mu\)W/cm\({}^{2}\))**} \\ \cline{2-6}
**VOCs** & **185 + 254 nm** & **222 nm** & **254 nm** & **367 nm** & **367 nm** \\  & **0.03** & **2.83** & **1.78** & **192** & **1968** \\  & **(0.01)** & **(0.59)** & **(0.37)** & **(40)** & **(410)** \\ \hline DMDS & 59.3 (0.14) & 59.8 (0.27) & 14.8 (0.70) & \(-\)14.7 (0.87) & \(-\)4.1 (0.93) \\ DMTS & 56.4 (0.15) & 67.1 (0.12) & 21.7 (0.50) & \(-\)6.2 (0.63) & 5.8 (0.86) \\ Acetic acid & 10.0 (0.68) & \(-\)12.2 (0.72) & \(-\)12.1 (0.70) & 0.4 (0.99) & **57.2 (0.04)** \\ Propanoic & & & & & \\ acid & 13.3 (0.83) & 37.4 (0.47) & 23.1 (0.64) & \(-\)32.6 (0.54) & 36.2 (0.49) \\ Isopentanoic & & & & & \\ acid & 24.9 (0.72) & 60.5 (0.39) & 70.0 (0.33) & \(-\)13.6 (0.85) & 18.1 (0.80) \\ Butanoic acid & 10.3 (0.66) & 27.8 (0.08) & \(-\)15.5 (0.79) & 21.8 (0.39) & **33.4 (0.03)** \\ Phenol & 43.4 (0.08) & 32.4 (0.26) & 7.8 (0.79) & 23.2 (0.53) & 24.7 (0.52) \\ \(p\)-Cresol & **47.1 (0.04)** & 46.9 (0.09) & 29.2 (0.32) & 8.9 (0.75) & 46.8 (0.05) \\ Indole & **54.2 (0.01)** & 19.2 (0.48) & 16.9 (0.51) & \(-\)14.5 (0.64) & 46.6 (0.17) \\ Skatole & 35.1 (0.35) & 55.8 (0.14) & 64.6 (0.11) & 3.7 (0.83) & 56.5 (0.09) \\ \hline \hline \end{tabular} Note: DMDS = dimethyl disulfide, DMTS = dimethyl trisulfide. Treatment time = 4.8 s (airflow = 0.25 m\({}^{3}\)/s), inlet and outlet air temperature = 16 \(\pm\) 1 \({}^{\circ}\)C and 19 \(\pm\) 2 \({}^{\circ}\)C.  
\end{table} 
Table 7: Mitigation of odorous VOCs with different UV wavelength irradiating gaseous emissions inside the #2 chamber. Bold signifies statistical significance. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**UV** & **UV Dose** & **Light Intensity** & **Control** & **UV** & **\% Reduction** \\
**Wavelength** & **(\(\mu\)/cm\({}^{2}\))** & **(\(\mu\)W/cm\({}^{2}\))** & **(ppb)** & **(ppb)** & **(\(p\)-Value)** \\ \hline
185 + 254 & 0.03 & 0.01 & 14.6 \(\pm\) 4.2 & 34.8 \(\pm\) 5.7 & \(-\)**139 (<0.01)** \\
222 & 2.83 & 0.59 & 18.6 \(\pm\) 2.2 & 0.0 \(\pm\) 0.0 & **100 (<0.01)** \\
254 & 1.78 & 0.37 & 16.8 \(\pm\) 2.9 & 0.0 \(\pm\) 0.0 & **100 (<0.01)** \\  & 192 & 40 & 10.9 \(\pm\) 2.1 & 7.7 \(\pm\) 2.4 & **30 (0.02)** \\
367 & 1968 & 410 & 6.4 \(\pm\) 1.6 & 0.2 \(\pm\) 0.7 & **97 (<0.01)** \\ \hline \hline \end{tabular} Note: Treatment time = 4.8 s (airflow = 0.25 m\({}^{3}\)/s), inlet and outlet air temp. = 16 \(\pm\) 1 \({}^{\circ}\)C and 19 \(\pm\) 2 \({}^{\circ}\)C.  
\end{table} 
Table 8: Mitigation of O\({}_{3}\) concentration with different UV wavelength irradiating gaseous emissions inside the #2 chamber. Bold signifies statistical significance.