Side-impact air bags (SAB) are inflatable devices that help protect your head and/or chest from being hit by hard objects in a side-impact crash. The first head SABs were introduced in model year 1998, but did not become widely available until recently. SABs, unlike frontal air bags, are not required by NHTSA. Because they are not required safety equipment, the Federal government does not mandate that vehicles be equipped with SABs. However, on September 11, 2007, NHTSA published a final rule that requires upgraded side impact protection. This rule, Federal Motor Vehicle Safety Standard (FMVSS) No. 214, Side Impact Protection, establishes new performance requirements. It's up to individual manufacturers to decide what type or types of protection systems - including SABs - they will use to meet the upgraded requirement.