WASHINGTON, D.C. — The National Transportation Safety Board (NTSB) on Tuesday concluded its investigation into the 2017 fatal school bus fire in Iowa, and called for several new school bus safety requirements, including the use of fire suppression systems on all school buses.

As SBF previously reported, the Dec. 12, 2017 school bus fire occurred when 74-year-old bus driver Donald Hendricks turned from a rural gravel road onto a driveway to pick up 16-year-old Megan Klindt at the farm where she lived in a rural area near the small town of Oakland.

According to a preliminary report released by the NTSB in January 2018, as Hendricks reversed out of the driveway, the bus’s rear wheels dropped into a 3-foot-deep-ditch. While Hendricks attempted to drive the bus out of the ditch, a fire began in the engine compartment and spread throughout the school bus.

The Iowa Office of the State Medical Examiner confirmed that both Hendricks and Klindt died from “smoke and soot inhalation and thermal injuries.”

In the report released on Tuesday, the NTSB determined that the probable cause of the fire was due to Hendricks’ failure to maintain control of the school bus — for reasons that could not be determined — and the failure of the Riverside Community School District to provide adequate oversight by allowing a driver with a known physical impairment to operate a school bus.

As SBF previously reported, a medical report recently released by the NTSB revealed that Hendricks had a history of medical issues leading up to the fire, including back pain and difficulty sleeping. However, the medical report did note that Hendricks was found to be qualified for a commercial driver’s license on an exam dated March 6, 2017, and that the certificate was valid for two years.

In opening the meeting, NTSB Chairman Robert Sumwalt pointed out that “drivers should be medically fit not only to operate the vehicle but also to assist in its evacuation in an emergency.” However, in the case of the Iowa school bus fire, Riverside Community School District allowed Hendricks to continue driving “despite the fact that the transportation supervisor, the school principal, and the driver’s coworkers knew of the driver’s physical impairment.”

The NTSB also noted in the report on Tuesday that the origin of the fire was the exterior of the engine’s turbocharger, and that investigators found that when the bus came to rest in the ditch, the exhaust was blocked. As Hendricks attempted to drive the bus out of the ditch, repeatedly accelerating the engine, it caused turbocharger overload with significant heat output which resulted in the fire, according to the report. Also contributing to the severity of the fire was the spread of flames, heat, and toxic gases from the engine into the passenger compartment through an incomplete firewall.

At the end of the meeting on Tuesday, NTSB approved a total of 10 new safety recommendations. The recommendations addressed issues that included school bus driver physical fitness, school bus fire safety, and emergency evacuation training.

Among the most notable recommendations were the NTSB’s calls on the U.S. Department of Transportation (U.S. DOT) and the National Highway Traffic Safety Administration (NHTSA) to require all school buses to be equipped with fire suppression systems.

The agency also urged the NHTSA to “develop standards for newly manufactured school buses, especially those with engines that extend beyond the firewall, to ensure that no hazardous quantity of gas or flame can pass through the firewall from the engine compartment to the passenger compartment.”

In addition, the NTSB recommended that 44 states, including the District of Columbia and Puerto Rico,  mandate annual physical performance tests for all school bus drivers, and also whenever their physical condition changes in a manner that could affect their ability to physically perform school bus driver duties, including helping passenger evacuate a bus in an emergency.

The agency also advised members of the National Association of State Directors of Pupil Transportation Services (NASDPTS), National Association for Pupil Transportation (NAPT), and National School Transportation Association (NSTA) to “verify that students are educated on how to operate the manual release handle for front-loading doors on school buses during evacuation training and drills.”

Barry R. Sudduth, president of NAPT, said in a statement on Tuesday that the organization “appreciates NTSB’s efforts to help bring clarity to this tragic event,” and that it “continues to believe possible scenarios in which drivers and students may be unable to extricate themselves — or not extricate themselves fast enough — merits special attention from the U.S. DOT and its component agencies.”

On Wednesday, NASDPTS and NSTA also released statements in support of the NTSB’s report and safety recommendations.

NASDPTS said in its statement that it “will consider all aspects of the report to support our shared goal of raising our safety bar even higher,” and that the association’s board “will discuss drivers’ fitness to perform their duties, including assisting in evacuation and training of students, and improving fire safety standards for school buses.”

The NSTA, however, did caution that initiatives that include retrofitting existing vehicles with fire suppression systems may not be consistent with original vehicle design, integrity, and warranty standards. The NSTA also said that these efforts should be fully funded or should be made at the state and local level where school budgets are resolved.

To view the full report and recommendations, go here.