Groundbreaking tests conducted by the IAFF and NIST to show the effectiveness of engine companies staffed with three firefighters opposed to engine companies staffed with two firefighters.  When Collinsville Fire Department is at minimum staffing, only two firefighters are on the engine at Station #1, located at 130 S. Clinton.

The following is the same study, but comparing four-person engines to three-person engines.  When CFD is at full staffing, four firefighters are on the engine at Station #1.  The North Side Firehouse, located at 1160 Beltline, is always staffed with three firefighters, regardless of shift staffing levels.