| Similarity | Rank | |
|---|---|---|
| dioxide | 0.897 | 4762 |
| sulphur | 0.839 | 6647 |
| monoxide | 0.834 | 12904 |
| nitrogen | 0.815 | 6386 |
| oxide | 0.811 | 7892 |
| particulate | 0.802 | 25930 |
| nitrous | 0.785 | 29606 |
| tetrachloride | 0.784 | 38419 |
| phosgene | 0.782 | 98640 |
| ethane | 0.781 | 70857 |
| hydrocarbon | 0.780 | 12320 |
| co2 | 0.778 | 18793 |
| hydrogen | 0.774 | 5285 |
| benzene | 0.766 | 21692 |
| methane | 0.766 | 11786 |
| emission | 0.765 | 3620 |
| vocs | 0.761 | 67555 |
| refrigerant | 0.756 | 52632 |
| cfc | 0.754 | 9251 |
| nox | 0.753 | 28969 |
| gaseous | 0.751 | 22356 |
| nitric | 0.745 | 22052 |
| &sub2; | 0.743 | 34174 |
| vanadium | 0.743 | 61827 |
| yttrium | 0.741 | 62626 |