Side Airbags and Side Curtain Airbags

Frontal airbags have proven themselves to be tremendous life saving devices. Their ability to save lives has been proven thousands of times. With this success, the National Highway Traffic Administration or "NHTSA" is encouraging car manufacturers for more safety devices that use the similar principles as the front impact air bags.

Thus, auto manufacturers are adding many new side and side curtain airbags as supplemental restraint systems to today's vehicle for additional occupant protection in case of a side collision or rollover. For example, Toyota released their 2006 Camry with standard equipment of 7 airbags and 2006 Hyundai Sonata with standard 6 airbags.

A Minnesota veteran paramedic with over 25 years of full time 911 response experience, Mike, said he had responded to a T-Bone collision at an intersection, and the side and side curtain airbags had deployed. Mike said, "the curtains were hanging down from the roof but nobody seemed to be injured in the vehicle."

Request for Responders to Complete a NHTSA, Special Crash Investigation (SCI) Form
If any side airbag or side curtain airbag deploys along an occupant seating position involved in ANY crash or incident:

All responders and technicians are requested to complete NHTSA's Special Crash Investigation Form. See www.nhtsa.dot.gov, click on "Airbags," scroll down to "Airbag Related Injuries and Fatalities," and click on "SCI Crash Notification Fax Back Form." Or go directly to www.nhtsa.dot.gov/departments/nrd-30/ncsa/TextVer/SCIForm.html.

The average vehicle may come with 4-6 airbags, standard or optional, including inexpensive vehicles. For overall growth, approximately 70% of new vehicles have side impact airbags or side curtain airbags. New safety innovations will change the way all first responders will work around these vehicles.

Why So Many Airbags?

In 2009 NHTSA, National Highway Traffic Safety Administration, (www.nhtsa.dot.gov) is requiring that all passenger vehicles and light duty trucks pass the new side impact crash test at approximately 20 mph into an equivalent car or pole size barrier. Approximately 1/4 of the nation's traffic fatalities result from crashes that are side impacts. One of the ways manufactures are providing additional side crash protection is by adding side and/or side curtain airbags. Side impact airbags are not required by NHTSA in vehicles. However, BMW's new 7, 6 and 5 Series can come equipped with 10-12 airbags, including knee airbags in the lower dash.

Other methods to protect occupants in side collisions may include: thickened tempered glass, laminated side glass, strengthening and reinforcing the side pillars and roof rails of the vehicle, thickening the door structures, strengthening the side impact door intrusion beam (FMVSS 214), or by adding a second side impact door intrusion beam. Foam inserts or blocks inside doors or foam injected into metal supports may also be used to absorb energy. Laminated glass may include the front side and/or rear side windows on some models.

Head Injuries Reduced

Studies have shown that most vehicles with side curtain airbags have a substantial reduction in head and neck injuries. Airbag manufacturers indicate the injury reduction may be up to 85%. Real world side crashes show that side curtain airbags reduce head and neck injuries to occupants in the vehicle sitting along side of the airbag and properly seat belted. The Insurance Institute for Highway Safety, IIHS, (www.highwaysafety.org) side crash test shows that occupants with side curtains are better equipped to receive lesser of an injury in a side collision with a side head or head curtain airbag. Incidentally, the IIHS side impact crash test is conducted at 31 mph with a larger pickup/SUV size barrier.

What's in a Side Airbag?

Most side curtain airbags utilize compress argon gas, an inert gas stored in a pressurized cylinder called a hybrid inflator. The hybrid inflator or canister is under pressure at 3000 psi. Side impact airbags deploy approximately 3 times as fast as the frontal airbags at .12 to .25 milliseconds. The leading edge speed of some airbags during deployment may approach speeds of approximately 495 mph. Remember there is less crush zone in a T-bone crash or side impact collision, so side airbags deploy faster than front impact air bags.

To protect the head and thorax of the human body, the side impact airbag deploys on the crashed or impacted side of the vehicle. Side impact sensors are mounted along the lower side of the vehicle to detect intrusion at an approximate 20 mph impact. The side impact sensors may be located in the front sides or rear side of the vehicle. The sensors signal the diagnostic energy reserve module, DERM, or airbag computer to deploy the side airbag in certain side impact collisions. Hybrid inflators can be located in A, B, C, or D pillars, roof, and or door of the vehicle.

Side Airbag Wires

Electronic wires will run from the DERM to the location of the side airbag to the seat, doors, side pillars and the roof rails. All wires will be of either bright yellow, orange or blue in color. They will also be labeled with tags identifying them as part of the "SRS" system. Side curtain airbag have fabric tether anchors that may be located in the side rails, A-B-C or D pillars. Caution is needed by rescuers not to cut into or puncture any part of the side curtain airbag hybrid inflator hidden underneath the vehicle interior trim. Be aware that hybrid inflator parts or debris, exposed or damaged fasteners, or broken clips that hold interior trim or curtain airbag in place during a collision, may break loose. Rescuers and EMS staff should wear protective equipment when working around these side and curtain airbag systems. Always respect the deployment pathway of any side or curtain airbag. Protect the patient in the vehicle from any loose fasteners, inflator debris or clips during the extrication process.

Seat Mounted Side Airbags

Most vehicle manufacturers have chosen to add side impact airbags in the outboard side of the front driver's and passenger's seats. Fewer have chosen to add side airbags to the rear seats. Look for the following labels along the seat back, base of the seat, SRS, SIPS, Airbag, SIR, IC, or HPS or on the trim of any head curtain airbag. Side airbags in the front seats may either be head-thorax or thorax (chest) size airbags depending on the model year and restraint options. Most side airbags are 5-8 inches wide and 12 inches long and tall. However, head thorax bags are 12-15 inches long and up to 24 inches tall. Extreme caution should be used while working around vehicles with airbags in the seat. A rescuer should not puncture the side airbag in the seat. If this were to occur, the airbag might deploy, generating hot gases. These hot gases would vent through the weakened bag at the tear and deflate prematurely and/or potentially burn or injure occupants sitting nearby.

Door Mounted Side Airbags

Some car manufacturers have chosen to place side impact airbags in the front and/or rear doors of the vehicles. Some door airbags may be seen in BMW, Cadillac, Mercedes, Land Rover and Porsche vehicles. Visualize the SRS label on the doors' interior trim panel. The new 2005 Porsche Boxster Carerra convertible has a window airbag that inflates vertically up and out of the top of the door panel. Volvo's newly redesigned C70 is expected to add the DMIC, door mounted inflatable curtain. Caution is advised in removing the door on these vehicles. Disable "SRS" before removing the door. If possible, wait appropriate Energy Reserve Module discharge time. Care must be used removing doors with door mounted airbags.

BMW Tubular Curtain

Most new BMW's come equipped with the HPS, Head Protection System, mounted along side of the front area of the vehicle. Look for the label HPS along the A-pillar trim of the vehicle. The airbag is anchored along the bottom of the A-pillar and extends to the rear anchor point behind the B-pillar. It is tucked up under the A-pillar trim and the headliner of the BMW. The inflation canister is located at the bottom of the A-pillar. Caution must be used in rescue on any vehicle with a HPS or head curtain airbag with anchors or airbag located in the A-pillar.

Window Airbags, Inflatable Curtains and Head Curtains

On cars, pickups and SUV's without 3-row seating, the curtain bag deploys along the side glass in side impact collisions, protecting both front and rear occupants, often remaining inflated for 6-10 seconds. The curtain is typically all a one-piece airbag approximately 5-6 feet long by 2-5 inches wide by 12-15 inches tall. The airbag is often anchored at the front and rear pillars of the vehicle with tether anchors. The bag is mounted into the roof rail and folded into a flat roll under the headliner of the vehicle.

Scan and Look for the side airbag labels anywhere along the interior side trim of the vehicle, most likely at the top of the A-B-C-D pillars or embossed on the headliner of the vehicle. Advise rescue of their location if outside the vehicle.

Third Row Curtains

Many new SUV's, minivans and crossover vehicles with third row seating now can come equipped with third row curtain airbags for side impact protection for the entire family. These side curtain airbags are up to 8 feet long and 15-24 inches tall and deploy along the entire side glass of the vehicle from the windshield to the back glass. Some models can have a single hybrid inflator; however, there are some vehicles with two hybrid inflators along the side or mounted in the pillars of the vehicle. I have seen some vehicles with segmented curtain airbags, in two separate sections, rather than one full length curtain. Some examples are on the Volvo XC90 7 seater, Infinity QX 56/Nissan Pathfinder Armada and Nissan Quest minivan. Note: Inflators for the curtain airbag are generally located at the top of the quarter glass or roof rail in many SUV's and wagons, so use caution during removal.

Roll-over Curtains

Some manufacturers have selected to deploy curtain airbags in certain roll over crashes in addition to side impact collisions. When this occurs, both side curtain airbags deploy in a roll over to mitigate head and neck injuries. Beginning in the 2002 model year, the "Safety Canopy System" was introduced in some Ford Motor Company SUV's and now is introduced in some cars and some minivans. Look for roll sensing curtain airbags in Acura, Dodge and Chrysler, Ford-Lincoln-Mercury, Honda, Jeep, Mercedes, Toyota and Volvo SUV's. For example, the new Acura TL as well as the Ford 500/Mercury Montego have roll over curtain sensor detection.

Some airbag safety recommendations for all are:

• Children 12 and under or (13th BIRTHDAY) ride in back seat
• Safest place for children with or without a frontal airbag is in the back seat; the back seat is 35% safer than front
• Always buckle children in right size child restraint seat or booster seat for every trip and every ride!
• If vehicle is equipped with side or curtain airbag, make sure children and other occupants do not lean into the side or curtain airbag
• Do not use seat covers on seats equipped with side seat airbags unless they are OEM approved
• See your owner's manual for more information about airbags

Golden Rules of Safety:

1. Always respect the deployment path of any side or side curtain airbag

2. Scan the interior trim, sides, doors, roof and pillars for any airbag system labeling. Observe any live airbag system with caution and advise all rescue staff working in the area. Check to make sure the airbag system has been deactivated when working near the deployment pathway of any airbag system.

3. Make sure the battery cables or airbag zone fuses have been disconnected, (if possible) wait for OEM deactivation time for reserve power to drain down inside airbag computer module. Make sure all wires have been shielded against reconnecting to terminals. Be aware of aftermarket accessories, which may have reserve battery power that may bleed power into the system.

4. If "peel before cutting" or "strip before ripping" technique is used, use care when removing any interior trim components to not damage the live airbag module or live curtain airbag. If cutting through the roof curtain airbag fabric or tubing, always consider the potential of gas under pressure and debris may be expelled out of the unprotected opening. Wear protective equipment. Protect the patient in the vehicle. If cutting through SRS wires in the side or pillars, always respect the deployment pathway of the airbag system when working around the vehicle as much as possible. Avoid cutting through the undeployed hybrid inflator module.

Although these are suggestions, each manufacturer will have different applications, as there is no standardized procedure to encompass them all. Some car manufacturers are considering voluntary guidelines for standardization for side airbag systems.

Dave Long, The Airbag Detective, Medic, RN is a national presenter and NHTSA CPS technician. E-mail him at davelong@northmemorial.com. Dave will speak on "New Car Anatomy for the 2006 Detroit Car Show" on September 27 at the 2006 EMS Expo Conference in Las Vegas. Dave and Jeff Payne, Vegas-based race car driver and President of Drivers Edge.org, will speak together at a preconference session on "Pitfalls of Driving Hot/Defensive Driving Tips from Experts" on September 26. On Friday, Dave will talk on his personal experience of "Back Injuries and Back Fitness." See www.emsexpo2006.com. Special thanks to technical knowledge and edits by Mitch Becker, Technical Consultant, ABRA Auto Body & Glass, and I-CAR Instructor.