Whenairbagsbecame required equipment on all U.S. automobiles in the 1990s , they represented a big spring forward for vehicle safety . Prior to that , driver and passenger had little more than theirsafety beltsto restrain and protect them in the event of a collision . Since their introduction , airbags have reduce driver fatality by 29 percent and passenger fatalities by 32 percent [ seed : Insurance Institute for Highway Safety].The National Highway Traffic Safety Administration account that in the three decades leading up to 2017 , head-on air bags saved 50,457 lives .

While airbags save up life sentence , they are n’t perfect . For children and masses of small height , the impact of an airbag inflating at more than 200 mph can cause lasting or deathly head and spinal hurt . This is the understanding that equipment driver are distinguish to put smaller passengers in the back seat . It ’s a law in some state . But what if you are carrying several passengers in the backseat and have to put a child up front ? What if you tug a two - seater motorcar ?

For that reason , car companies are required to equip certain vehicles withOccupant Classification Systems(OCS ) — a system of sensors that detect who ’s sit in the passenger fanny . OCS annihilate the need for an on / off switch for airbags in most slip because it uses advanced computer engineering science to identify whether an adult or a fry is in the keister .

Before we take a look at Occupant Classification Systems , let ’s review how theairbagitself works . In the event of a crash , a sensing element spark off a nylon bag inside the steering rack , room access and/or dashboard to instantly fill with compressed nitrogen gas . The goal of this is to cushion the occupant from a powerful impingement .

In this article , we ’ll explore the development and consumption of Occupant Classification Systems , and look at why airbags are still no replacement for safe belts .

OCS Sensors

Imagine this scenario : You and your family are moving into a fresh house . The tree trunk and back tooshie of your car are engorge with your belongings , but you have to take your seven - year - former daughter along for the ride . You have no choice but to put her in the front passenger seat . But will she be safe up there ? What happens if there ’s a wreck ? What will the airbags do to her ?

It ’s never a good idea to put your kid in the front fanny , but sometimes reality force driver to do otherwise . If you ’re driving an American railway car or motortruck made after 2006 , you ’re probably hunky-dory , since they all contain some method acting of airbag suppression — most likely , an OCS .

Let ’s take a tone at one pop OCS made by Delphi . Inside the seat , you will find a press detector , a silicone polymer - fill " vesica , " and an electronic control unit ( ECU ) . When someone sit on the rear end , the pressure sensor signal the occupant ’s weight to the ECU . The ECU then transport that data to the airbag , which has its own ascendence unit . Based on that information , the vehicle ’s computer turns the passenger airbag on or off .

The OCS does n’t just discover system of weights . It read the passenger ’s seating stead and determines if they ’re fag out a seat belt . It also has a seat belt tension sensor that allow the OCS to understand the pressure create when a child seat is fitted . In other words , the system is designed to tell whether a child guard fundament is occupying that seat or whether you ’re just carry some sound object there . A light or contract on the instrument panel tells the equipment driver whether the passenger airbag is on or off .

Once the onboard computer do it the rider ’s size and exercising weight , the car’sdual stage airbagscome into play . base on the occupants ' size , these type of airbags can deploy at full speed , partial stop number , or not at all . An airbag deploy at full speed can mischievously wound or even kill a child or small adult . In improver , dual degree airbags also can deploy at less amphetamine when the railway car is involved in a minor hit . Remember — even on car equipped with an OCS , it ’s always safest to keep small children in the back seat .

In the next section , we ’ll take a look at the history of airbag sensor systems , and why they ’re necessary in the first situation .

History of the OCS

Drivers require a pile from forward-looking automobile in footing of safety features . Airbags were range in cars to shrink fatalities , but early on on they experienced problems of their own .

Part of the problem with early airbags was that consumer expected them to replaceseatbelts , enunciate Rae Tyson , a spokesman for the National Highway Traffic Administration . " This could not be further from the truth , " Tyson said . " The airbag was never think to be a main safety gimmick , but a addendum . "

Early airbags were overly belligerent to protect these kinds of motorists , Tyson suppose , which conduct them to be too forceful and deploy too easily . As such , new system — like the OCS — had to be developed to keep combat injury and deaths down . In 2000 , the U.S. Transportation Secretary issue a principle requiring that airbags on cars made after 2006 create less risk of serious hurt , particularly for women and child of smaller size . This rule encourage automakers to habituate technologies like weight sensors and threefold - stage airbags to get the job done .

The rule also requiredcrash testson vehicles to includedummiesof diminished women and children in addition to median sized men , which were previously the only pinhead require . In add-on , the jurisprudence required a manner for " downcast peril " airbags to deploy if a baby is sitting in the passenger tail end during a clangoring to keep them from being injured . The mandate also called for suppression of the airbag for rear - facing babe seats and forward - facing child behind , while enabling the airbag for passengers as small as a five feet tall and 110 lb [ source : National Highway Traffic Safety Administration ] .

Today , as part of the authorisation , systems like these can be found on every new railroad car made in America after 2006 . Every system does n’t have to be the same , Tyson say . It ’s up to car manufacturers to figure out a way to meet the standard . They can do this with several technologies . Modern airbags have advanced a great bargain , and carmakers are n’t seeing the same problems they visualize in the yesteryear . train motorists to keep kids in the back and to sit away from the airbag deployment zona has keep injuries down as well , Tyson said .

Next , we ’ll look at the advantages and disadvantages associated with Occupant Classification Systems .

OCS Advantages and Disadvantages

There are lots of welfare to consume an OCS and dual - stage airbags in your car . They pose less of a menace to children and small adults , and they allow drivers more options for seating their rider . It also means that airbags will not damage inanimate target position in the rider seat .

That does n’t mean that other versions did n’t have their problems . Sometimes the OCS did n’t properly feel the passenger , which led to the airbag being turned on or off when the opposite should have come about . Also , some smaller passengers noticed that the airbag would turn on or off look on how they sat in the tail , as if the airbag was unable to decide whether an grownup or child was sitting there . In other instances , the OCS was overly sensitive — placing a newspaper in the passenger seat would trigger the airbag to switch on , for example . Hyundai , Jaguar , Jeep , Lexus , Nissan and Toyota vehicle all see similar problems , which led to complaint to the NHTSA [ beginning : Edmunds.com ] .

With clock time , these job were mostly set , and airbags are now safer than ever before . Occupant Classification Systems have made airbags safer and cut down on airbag - related death , the NHTSA ’s Tyson said . " It ’s work out fabulously . We ’ve gone from a base hit arrangement with unintended consequences to one with [ no consequences ] . We ’ve had no airbag fatalities in recent year . "

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