A side airbag system comprising a 12 litre bag to cover the chest and the abdomen down to the arm rest level and 75 mm of padding to cover the pelvic/thigh area was evaluated by a series of sled tests at two different velocities, 10 m/s and 12 m/s. The initial bag (over) pressure was varied from 0 to 80 kPa and the bag ventilation area was varied from zero to 1500 mm². Compressed air was used to fill the bag.

It was found that the ventilation of the bag reduced the maximum chest deflection by 30% and the maximum viscous criterion, VC, by 50% (comparison was made with the same bag without ventilation). A suitable initial bag (over) pressure was found to be about 40 kPa, when also the the loading of the abdomen was taken into consideration.

The results indicate that the chest deflection is proportional to the door average velocity (during the first 20 ms of deflection) to the power of about 2 and that the VC is proportional to the same velocity to the power of about 4.

It was also found that a 12 litre ventilated side airbag resulted in 30-40% lower chest deflection and about 60% lower VC than 50 mm chest padding (Ethafoam 220).