Each vehicle is assigned a call-sign consisting of a 4 digit number. The first two numbers will always be the same for Middlebrick Fire units; the number 38. This is the assigned number of Middlebrick Fire in the county. Each other fire department in the county has it's own unique number as well. Following the first two digits is another number ranging from 2-9. Each designates the apparatus to a certain function. For example, 2 designates engines, 3 correlates to tankers and 4 to ladders and so on. The final digit designates the unit number in the department.