My car is sinking: automobile submersion, lessons in vehicle escape

In North America approximately 400 individuals per year die in submersed vehicles, accounting for 5-11% of all drownings. About half of people surveyed would let the vehicle fill with water before attempting exit.

We used a crane and two passenger vehicles of the same make, model, and year-one with passenger compartment intact (I) and one with holes (H) in the floor (area approximately 2200 cm2)--to conduct occupied and unoccupied submersions.

Three phases of submersion were identified: 1) FLOATING, vehicles floated for 15 s (H) to 63 s (I) before the water reached the bottom of the side windows; 2) SINKING, the subsequent period until the vehicle is completely under water, but before it fills completely; and 3) SUBMERGED, the vehicle was full of water and several feet below the surface. Total time to submersion was 150 s for I but only 37 s for H. Opening the door to exit Vehicle I decreased submersion time from 150 to 30 s. Even the most difficult exit strategy attempted (three men and a child manikin through one window) was quickly performed from Vehicle I (only 51 s). During one exit attempt, initiated during the sinking phase, it was impossible to open the doors or windows until the vehicle was completely full of water.

A vehicle is most easily exited during the initial Floating Phase. We suggest the following escape procedure: SEATBELT(s) unfastened; WINDOWS open; CHILDREN released from restraints and brought close to an adult; and OUT, children should exit first.