2004 Almanac (page 26)  Table 1-4

State CO Standards:
20 ppm for 1 hour and
9.0 ppm for 8 hours,
neither to be exceeded.
		
6 ppm for 8 hours
(Lake Tahoe Air Basin only),
not to be equaled or exceeded.
		
National CO Standards:
35 ppm for 1 hour and
9 ppm for 8 hours,
neither to be exceeded more
than once per year.