BMW Technology - F.I.R.S.T

Safety F.I.R.S.T from BMW. Fully Integrated Road Safety Technology (F.I.R.S.T) is a comprehensive and integrated approach to design and engineering for optimum safety systems in three parts:

• Active Safety that helps you steer clear of hazards,
• Passive Safety that protects you from certain kinds of collisions, and
• Protection to minimize the impact on other road users and the vehicle itself

BMW was the first car manufacturer in the world to offer head airbags. Now, BMW has taken the next step by offering "intelligent" front airbags. The intelligent airbag system, called Dual Stage Deployment, inflates the two front airbags in stages, depending on the severity of the impact. This gradual deployment of the vehicle's airbags minimizes the risk of being hurt by the opening of the airbag in a collision. Intelligent airbags are standard equipment on all 3, 5 and 7 Series BMW models.

Run-flat systems have been around for a number of years in many different forms - Dunlop Denovo, Michelin/Dunlop TD system, Bridgestone/Dunlop Denloc system. To name but a few. Over the years manufacturers have adopted several different systems but all with one goal in mind - vehicle safety. Run-flat tyres are designed to keep the tyre beads securely anchored to the rim flange area of the wheel even when operating at zero pressure.

BMW being the biggest user. Many models of BMW are now available with Run-flat tyres - the 1 series, new 3 series, 6 series and Z4 and Z8 models are all equipped 100% with Run-flat tyres, 5 series and 7 series are available with Run-flat as an option. Special reinforced side walls and lateral supports in the tyre, plus a fire-resistant rubber compound, keep the run-flat tyres stable and safe for up to 150 km at 80 km/h. Driver-assistant features remain active, and the Sedan can be driven to the next service station. A spare tyre is not needed.

With an integrated airbag, the steering wheel is comprised of high passive safety with a high quality and elegant design.

• In the event of a frontal collision with a pre-defined minimum force ( approx. 30 km/h ), sensors activate the airbag inflation gas.
• The airbag inflates within a fraction of a second. In conjunction with the 3-point seat belt, it effectively protects the head and upper body from impacting against the steering wheel.
• The control lamp in the instrument cluster provides constant monitoring of the system.

Your benefits :

• maximum safety in conjunction with an integrated airbag
• optically appealing and perfectly integrated within the steering wheel

Function in detail :

In the event of a frontal collision, an electronic acceleration sensor transmits information to an evaluation unit that decides within a few milliseconds whether an accident is sufficiently serious to warrant ignition of the airbag. As soon as the predefined threshold (approx. 30 km/h) is exceeded, a safe sensor switches and the airbag is ignited.

Ignition is ensured by an electro-pyrotecnical ignitor, which causes a nitrocellulose pellet weighing about 8 grams to react. The gas generated in this process fills the airbag within 20-25 milliseconds, and a catalytic converter downstream of the gas generator reduces the emission of CO to avoid any harmful effects to the occupants.

The airbag itself consists of silicon-coated polymide tissue. The volume is sufficient enough to almost completely prevent the risk of the seatbelt-wearing driver from impacting against the steering wheel. The system is constantly monitored for safety. A control lamp in the instrument panel indicates to the driver that it is ready for use.

If the car can still be driven after an accident during which the airbag is activated, steering of the vehicle will be slightly impaired by the open airbag. However, the entire airbag unit can be removed immediately by the nearest BMW workshop. Once ignited, the airbag must be completely replaced by BMW's customer service.

How Airbag Works

The airbag is stored inside the steering wheel or instrument panel, and it inflates instantly to protect the passenger in the event of a head-on collision. It is intended to be used as a supplementary device to the seat belt. Many BMWs have airbags designed to protect passengers from side collisions as well.

Airbag systems consist of a sensing device (acceleratometer), that sends an airbag inflate signal to the airbag when a collision is detected, and a bag module that activates a compressed gas system that inflates the air bag when it receives the inflate signal.

When the collision detection circuit detects an impact, a microcomputer in the system triggers the inflation system in the airbag, which begins to inflate approximately 1/10th of a second after detection. This is quicker than the blink of an eye.

ITS head airbag for driver and passenger

Statistics show that the number of people injured in side-impact collisions - the second most common type of accident - is increasing. With the ITS head airbag, the particularly sensitive head area is effectively protected.

• In the event of a side-on collision, a gas generator is ignited. This activates the ITS head airbag, which is housed in the side of the roof frame.
• This spreads itself diagonally across the front door window and prevents the head from directly hitting penetrating obstacles.

Your benefits :

• ideal addition to side airbag and side-impact protection system in the doors
• entire seating adjustment area is covered
• protects the head from glass splinters when side windows smash

Function in detail :

In a side-on collision, the thorax and abdomen are especially at risk, as well as the head. The ideal side protection system should therefore provide effective protection for the head and the chest. This is why BMW has added an effective head protection function to the existing side protection system - the BMW ITS (Inflatable Tubular Structure) head airbag.

The ITS head airbag is housed at the side of the roof frame and is attached directly to the body by means of belts. In the event of a side-on collision, the fabric tube is inflated after the ignition of a gas generator. This draws itself from front to back out of the roof lining and spreads across the front door window. The whole tube is hermetically (airtight) sealed. A drop in pressure only occurs when the gas cools after a period of time.

Components :

• airbag module, comprising gas generator, tube-type airbag and attachment belts
• no special activating sensors are necessary, since the side airbag sensors are used