one of seven size categories of fire determined by the area burned: Class A (< 0.25 ac or < 0.1 ha), Class B (0.25 to 10 ac or 0.1 to 4 ha), Class C (10 to 100 ac or 4 to 40 ha), Class D (100 to 300 ac or 40 to 121 ha), Class E (300 to 1,000 ac or 121 to 405 ha), Class F (1,000 to 5,000 ac or 405 to 2,024 ha), Class G (> 5,000 ac or > 2,024 ha) —synonym fire size class, size class This definition last updated 07/18/2008