When it comes to automotive steel, two groups of experts are working together to enhance the state of the art for driver and passenger safety. Both emergency first responders and auto body repair professionals respect and value how modern automotive advanced high-strength steels (AHSS) and ultra high-strength steels (UHSS) have improved the safety of today’s cars and trucks.
Technological advances in steels and design have made vehicles safer in a collision. They have also changed many of the long-standing techniques and practices for fire and rescue professionals who save lives at accident sites, as well as the body shop personnel who ensure vehicles are safely repaired before getting back on the road. This can range from changes in strategy to entire new toolkits. Both body shops and first responders have had to upgrade their tools to handle AHSS and UHSS. This can include reciprocating saws, air chisels and hydraulic rams, spreaders and shears.
“Over the last decade, rescue tool manufacturers recognized what was going on with high-strength steels,” explains Ron Moore, a former battalion chief in a suburban Dallas-Fort Worth fire department and nationally-recognized expert on extrication. “Starting around 2008 or 2009, they began to produce a whole new generation of more powerful tools and new designs. Pretty much every fire department has traded in their older-generation gear, which usually dated back to the 80s or 90s but had since been outgunned by high-strength steels.”
SMDI works with Moore, who authored the widely used textbook, “Vehicle Rescue and Extrication,” to get the best perspective on how AHSS and UHSS are changing the way rescue personnel interact with vehicles when extrication is necessary. Moore trains fire, rescue, EMS and law enforcement personnel across the nation on how to safely rescue and extricate drivers and passengers from vehicles of all kinds. He’s also shared his expertise with automotive repair personnel, explaining how emergency personnel operate an impromptu “body shop in reverse” on the side of the road in an emergency situation.
The basics of extrication are a constant, Moore explains. Rescue personnel need access to the people inside the vehicle, room to work on them in place, if necessary, and a path for safe removal of all involved. This can range from the standard “door job,” as taking a door off the car is known in the fire rescue community, to removing instrument panels, roofs or pillars, forcing compartments open and more.
Where there has been crushing, bending or folding of vehicle structures, putting occupants at risk, rescue personnel can either move or remove those parts of the vehicle based on the requirements of the specific situation. The materials involved factor into this decision on the scene, as some tactics such as door frame spreading with a portable hydraulic ram, which worked in the past with traditional steel body structures, may fail when AHSS or UHSS are involved.
Tougher Vehicles, Tougher Opponents
In general, Moore calls modern AHSS-intensive vehicles a “tougher opponent” for rescue personnel thanks to the strength of the materials they’re now working against, often in a race against the clock. While the increasing crashworthiness of vehicles means fewer extrication jobs, the new strength of the materials they’re modifying means, “when they are trapped, we have more work to do,” explains Moore.
“It’s becoming the norm for side-impact collisions with people trapped inside to remove the B-pillar altogether, and increasingly we’re ‘making the car a convertible’ by taking off the roof,” he explains. In the past, spreaders could move B-pillars far enough out of the way for most access needs, but the strength built into modern AHSS-intensive B-pillars means they are so hard to bend out of the way rescuers find it easier to cut through three sides and then use a spreader to bend it out of the way, if not remove it entirely.
High-strength steel and advanced high-strength steel are used in the 2018 Honda Odyssey’s A, B and C-pillars, roof rails, front and rear rails and front subframe, allowing the vehicle’s cabin structure to better manage front, side, roof and rear collisions.
Additionally, many traditional techniques involved “crush-then-cut” of stamped steel components. With the advent of AHSS, crushing became so difficult to accomplish, techniques evolved to rely more on cutting through AHSS and UHSS assemblies which were designed to ensure occupant safety by resisting crushing-type forces.
Moore expects extrication will continue to evolve as UHSS become more common, which means repairing vehicles from extrication will continue to be more complicated. “The first-generation AHSS didn’t fight us the way third-generation AHSS does,” he says. “We’re up against a tougher opponent, one that often requires more extensive work. For instance, we’re finding that cutting is often necessary where spreading had been sufficient in the past.”
The new 2019 Ram is the strongest 1500 to date, featuring 54 percent high-strength steel in the cab and more than 98 percent high-strength steel in the frame. The use of high-strength steel in the frame enables noise-, vibration- and harshness (NVH) reduction measures, weight savings of nearly 225 pounds and greater rigidity for improved handling and durability.
Worth the Work
According to Moore, emergency personnel appreciate the value of modern steels and often seek out AHSS-intensive vehicles for their own families. This is because fire departments are increasingly arriving at crash scenes where, in his words, “The cars are bent, crumpled and folded and we expect the worst, but the drivers are standing outside exchanging insurance information because the structure of the vehicle remained intact.”