|  | Spruce |  | Pine |  |
---|---|---|---|---|---|
parameter | Unit | 4 h average | Tox-ALI | 4 h average | Tox-ALI |
NO | ppm | 1.9 ± 1.2 | 1.9 ± 1.2 | 1.7 ± 0.8 | 1.7 ± 0.7 |
NO2 | ppm | 0.2 ± 1.1 | 0.2 ± 0.5 | 0.2 ± 0.4 | 0.2 ± 0.7 |
THC | ppm | 12.3 ± 28.2 | 16.1 ± 27.8 | 9.3 ± 18.8 | 9.4 ± 23.8 |
CO | ppm | 122 ± 141 | 142 ± 149 | 84 ± 94 | 67 ± 88 |
CO2 | ppm | 4500 ± 1700 | 4600 ± 1900 | 4300 ± 1400 | 4300 ± 1300 |
PM1 mass (SMPS) | mg m− 3 | 4.3 ± 5.1 | 4.9 ± 6.0 | 6.2 ± 5.1 | 7.7 ± 6.5 |
TSP mass (TEOM) | mg m− 3 | 6.0 ± 7.8 | 7.4 ± 9.1 | 9.6 ± 7.6 | 12.3 ± 10.2 |
PNC (SMPS) | 1 × 106 cm− 3 | 2.1 ± 1.5 | 2.4 ± 1.8 | 2.1 ± 1.3 | 2.1 ± 1.5 |
PNC (ELPI) | 1 × 106 cm− 3 | 2.7 ± 3.8 | 3.2 ± 3.5 | 2.9 ± 2.2 | 3.1 ± 2.1 |
LDSA (NSAM) | 1 × 106 μm2 cm− 3 | 16.9 ± 18.1 | 20.5 ± 22.7 | 21.7 ± 15.6 | 24.8 ± 17.9 |
MMD (SMPS) | nm | 304 ± 167 | 322 ± 168 | 365 ± 146 | 414 ± 102 |
GMD (SMPS) | nm | 91 ± 29.2 | 94.3 ± 32.3 | 110 ± 32.7 | 120 ± 27.9 |
OC | μg m− 3 | 570 ± 160* | 2100 ± 320 | 790 ± 340 | 850 ± 80* |
EC | μg m− 3 | 4100 ± 1300* | 4500 ± 1200 | 7900 ± 1500 | 6600 ± 3700* |
OC/EC |  | 0.14 ± 0.01 | 0.47 ± 0.05 | 0.10 ± 0.03 | 0.20 ± 0.12* |
ECF | m3 of exposure aerosol /MJ fuel energy | 11.0 ± 1.2 | 11.0 ± 1.4 | 11.3 ± 0.2 | 11.4 ± 0.3 |