A prerequisite for this two week course is completion of Crash Invest. one. This intense class builds on CI-1 and covers interpreting tire marks, road scars, advanced measuring methods, vehicle damage analysis and vehicle behavior during collisions. This course is also known as advanced or technical training. If applicants had a problem with the math involved in CI-1 they should hone their algebra skills prior to signing up for CI-2 since there is a noticeable emphasis on math formulas as they relate to collisions.