Side Impact Protection System

SIPS or Side Impact Protection System is the name of a system to protect against injury in a side collision, developed by Volvo.

SIPS was first introduced in 1991 for the Volvo 700, 900 and 850 series cars of model year 1992. It has been standard on every new Volvo since.

The SIPS system works by having a reinforced lower sill, b-pillar and energy absorbing honeycomb materials inside the doors. The idea is to more widely distribute the energy in a side collision across the whole side of the car rather than having the b-pillar absorb it all. Driver and passenger seat are mounted on transverse steel rails, not bolted to the floor as per the standard configuration. In a side impact these transverse rails allow the seats to crush a reinforced center console designed to absorb additional energy.

In 1994 for the 1995 model year, the 'SIPS-Bag' was released for 850 models. Initially an option, it became standard equipment of all new Volvo cars beginning in 1995. The system consists of a mechanically activatedairbag that protects the torso from hitting the cars interior. In 1998 two additions were made to the SIPS system. With the launch of the 1998 Volvo S80 the IC airbag, a curtain style airbag deploying from the headlining to protect the head, was introduced. It has since been standard equipment on all newly released Volvos.
Because of technical reasons the existing Volvo S70, V70 and C70 models were instead equipped with the 'SIPS-BAG II'.

Volvo S80 cutaway showing part of the SIPS system components

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