Table 1
Proposed Colorado Natural Gas-Fired Reciprocating IC Engine Limits
| Maximum Engine HP | Construction or Relocation Date | Emission Standards in G/HP-HR | ||
| NOx | CO | NMHC | ||
| 100 < HP < 500 | January 1, 2008 | 2.0 | 4.0 | 1.0 |
| 100 < HP < 500 | January 1, 2011 | 1.0 | 2.0 | 0.7 |
| 500 < HP | January 1, 2007 | 2.0 | 4.0 | 1.0 |
| 500 < HP | January 1, 2010 | 1.0 | 2.0 | 0.7 |