Maryland Emission Standards
Idle Standards 2009 (PDF)
| Weight Group | Model Year | HC (ppm) | CO (%) |
|---|---|---|---|
| 0 - 6,000 lbs Gross Vehicle Weight |
1977 | 500 | 6.00 |
| 1978 | 430 | 5.50 | |
| 1979 | 400 | 4.00 | |
| 1980 | 220 | 1.70 | |
| 1981 - 1990 | 220 | 1.20 | |
| 1991 - 1992 | 200 | 1.00 | |
| 1993 - 1995 | 175 | 1.00 | |
| 6,001 lbs - 10,000 lbs Gross Vehicle Weight |
1977 | 580 | 7.00 |
| 1978 | 550 | 6.70 | |
| 1979 | 470 | 5.00 | |
| 1980 | 350 | 5.00 | |
| 1981 | 250 | 3.00 | |
| 1982 | 220 | 2.50 | |
| 1983 | 220 | 1.50 | |
| 1984 - 1990 | 220 | 1.20 | |
| 1991 - 1992 | 200 | 1.00 | |
| 1993 - 1995 | 175 | 1.00 | |
| 1996 - 2000 | 125 | 1.00 | |
| 2001+ | 100 | 0.75 | |
| 10,001 - 26,000 lbs Gross Vehicle Weight |
1977 - 1978 | 650 | 7.00 |
| 1979 | 650 | 6.50 | |
| 1980 - 1982 | 500 | 6.00 | |
| 1983 | 500 | 3.50 | |
| 1984 - 1985 | 440 | 3.00 | |
| 1986 | 280 | 2.50 | |
| 1987 - 1992 | 220 | 1.20 | |
| 1993 - 1995 | 200 | 1.00 | |
| 1996 - 2000 | 125 | 1.00 | |
| 2001+ | 100 | 0.75 |