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Safety Recommendation Details

Safety Recommendation H-97-038
Details
Synopsis: ABOUT 3:25 P.M. A 1988 MACK TRUCK WITH A CONCRETE MIXER BODY WAS UNABLE TO STOP AS IT APPROACHED A "T" INTERSECTION AT THE BOTTOM OF AN EXIT RAMP IN PLYMOUTH MEETING, PENNSYLVANIA. AS THE TRUCK PROCEEDED THROUGH THE INTERSECTION, IT COLLIDED WITH & OVERRODE A 1985 SUBARU PASSENGER CAR. THE SUBARU DRIVER WAS KILLED; THE TRUCKDRIVER SUSTAINED MINOR INJURIES. THE TRUCKDRIVER WAS UNRESTRAINED; THE SUBARU DRIVER WAS FOUND RESTRAINED IN HER VEHICLE. THE WEATHER WAS CLEAR & DRY. NO FIRE ENSUED, & NO OTHER VEHICLE OCCUPANTS WERE INVOLVED IN THE ACCIDENT.
Recommendation: THE NTSB RECOMMENDS THAT THE NHTSA: IN COOPERATION WITH THE SOCIETY ENGINEERS, DEVELOP SPECIFICATIONS & REQUIREMENTS FOR THE INSTALLATION, IN HEAVY TRUCKS WITH A DUAL AIR BRAKE SYSTEM, OF SEPERATE LOW-AIR-PRESSURE WARNING DEVICES THAT WILL INDEPENDENTLY ALERT DRIVERS TO A LOSS OF AIR PRESSURE IN EITHER SYSTEMS.
Original recommendation transmittal letter: PDF
Overall Status: Closed - Unacceptable Action
Mode: Highway
Location: Plymouth Meeting, PA, United States
Is Reiterated: No
Is Hazmat: No
Is NPRM: No
Accident #: NRH96FH009
Accident Reports: Truck Loss of Braking Contol on Steep Downgrade and Collision with a Vehicle
Report #: HAR-97-02-SUM
Accident Date: 4/25/1996
Issue Date: 10/29/1997
Date Closed: 4/5/2001
Addressee(s) and Addressee Status: NHTSA (Closed - Unacceptable Action)
Keyword(s):

Safety Recommendation History
From: NTSB
To: NHTSA
Date: 4/5/2001
Response: The Safety Board is disappointed that NHTSA has not taken a more active approach regarding this recommendation. Although NHTSA’s Office of Defects Investigation has received no complaint of a defective or inadequate low-air-pressure warning device, the Safety Board is concerned that a significant number of dual-air-brake-system-equipped trucks nationwide may have undetected air brake deficiencies similar to those found on the trucks involved in the accident. As stated in our 1997 accident report, JDM Materials Company, Inc., of Plymouth Meeting, Pennsylvania, inspected its entire fleet to determine whether any more vehicles had reversed air brake lines and/or inoperative low-air-pressure warning switches. This inspection of the company’s 165-truck fleet revealed that 2 additional trucks had reversed air lines, and 12 additional trucks had inoperative low-air-pressure warning switches; in total, more than 8 percent of JDM’s fleet had defective air systems. As all the defective air systems were repaired and tested in accordance with the brake manufacturer’s guidelines by company personnel, no deficiencies were reported to NHTSA. Because NHTSA has not acted on this important safety issue, Safety Recommendation H-97-38 is classified “Closed--Unacceptable Action.”

From: NHTSA
To: NTSB
Date: 9/8/2000
Response: Letter Mail Controlled 09/12/2000 MC# 2001273 In March, 1998, NTSB, NHTSA, and FHWA staff met to discuss this recommendation. All parties agreed that the crash that led to this recommendation involved a truck that had a defective warning switch, a defective or broken reservoir drain valve, and switched brake lines. NHTSA believes these issues are related to inspection and maintenance of the vehicle. FHWA OMCS (now FMCSA) indicated they planned to conduct a special roadside inspection of low-air-pressure warning switches to help determine whether this is a significant safety problem. FMCSA has not yet conducted its special investigation of low-air-pressure warning switches. In July 2000, NETSA again reviewed complaints that have been filed with our Office of Defects Investigation. We have not received a single complaint of a defective or inadequate low-air pressure warning device. NHTSA requests that this recommendation be closed based on acceptable action.

From: NTSB
To: NHTSA
Date: 7/13/2000
Response: ON 7/13/00 THE SAFETY BOARD MET WITH NHTSA REGARDING THE IMPLEMENTATION OF THIS RECOMMENDATION. NHTSA PROMISED TO SEND A RESPONSE WITHIN 30 DAYS.

From: NHTSA
To: NTSB
Date: 5/19/1998
Response: Letter Mail Controlled 5/21/98 12:21:24 PM MC# 980655 AS STATED IN YOUR LETTER, NHTSA IS PLANNING TO CONDUCT A SPECIAL ROADSIDE INSPECTION OF LOW-AIR PRESSURE WARNING SWITCHES OF IN-SERVICE TRUCKS TO DETERMINE THE SCOPE OF THE INOPERATIVE SWITCH PROBLEM. ACCORDINGLY, UNTIL THIS STUDY IS COMPLETED, WE WILL NOT TAKE REGULATORY ACTION AT THIS TIME. ANY SUCH ACTION WOULD BE BASED, IN PART, ON EVIDENCE THAT THERE IS A WIDESPREAD PROBLEM WITH THESE SWITCHES. WE WILL, THEREFORE, ACCEPT YOUR CLASSIFICATION FOR H-97-38 AS "OPEN--ACCEPTABLE RESPONSE."

From: NTSB
To: NHTSA
Date: 4/15/1998
Response: THE BOARD HAS REVIEWED THE EXISTING REQUIREMENTS OF FEDERAL MOTOR VEHICLE SAFETY STANDARD NO. 121, AIR BRAKE SYSTEMS, AS DISCUSSED IN YOUR LETTER. THE BOARD UNDERSTANDS THAT THE STANDARD CURRENTLY PERMITS A COMMON LOW-AIR-PRESSURE WARNING SIGNAL, (THAT IS, NONE LIGHT & ON bUZZER), TO BE USED FOR ALL SERVICE RESERVOIR SYSTEMS. NONETHELESS, THE BOARD REMAINS CONCERNED, BECAUSE IN THIS ACCIDENT, THE STANDARD DID NOT PROVIDE FOR SPARATE LOW-AIR-PRESSURE WARNING DEVICES ON HEAVY TRUCKS THAT HAVE DUAL AIR BRAKE SYSTEMS. ON 3/18/98 SAFETY BOARD STAFF MET WITH REPRESENTATIVES OF BOTH THE FHWA & NHTSA TO DISCUSS THE FACTS & CIRCUMSTANCES OF THE PLYMOUTH MEETING ACCIDENT. ALL PARTIES AGREED THAT THE INSPECTION OF LOW-AIR-PRESSURE WARNING SWITCHES IS A CRITICAL ISSUE. IN THAT REGARD, THE FHWA, OFFICE OF MOTOR CARRIER SAFETY, WILL CONDUCT A SPECIAL ROADSIDE INSPECTION OF LOW-AIR-PRESSURE WARNING SWITCHES LATER THIS SUMMER. THIS INSPECTION OF LOW-AIR-PRESSURE WARNING SWITCHES WILL DETERMINE WHETHER A SIGNIFICANT NUMBER OF TRUCKS EQUIPPED WITH DUAL AIR BRAKE SYSTEMS NATIONWIDE HAVE UNDETECTED AIR BRAKE DEFICIENCIES SIMILAR TO THOSE FOUND ON THE ACCIDENT TRUCK. THE BOARD STANDS READY TO ACTIVELY PARTICIPATE IN THE UPCOMING COMMERCIAL VEHICLE INSPECTIONS, & WE LOOK FORWARD TO RECEIVING A FURTHER RESPONSE FROM YOUR OFFICE ON THIS RECOMMENDATION. IN THE MEANTIME, H-97-38 IS CLASSIFIED "OPEN--ACCEPTABLE RESPONSE."

From: NHTSA
To: NTSB
Date: 12/5/1997
Response: WITH REGARD TO YOUR RECOMMENDATION THAT "SEPARATE LAW-AIR-PRESSURE WARNING DEVICES THAT WILL INDEPENDENTLY ALERT DRIVERS TO A LOSS OF AIR PRESSURE IN EITHER SYSTEM" BE INSTALLED, WE DO NOT BELIEVE THERE WOULD BE ANY SAFETY BENEFIT FROM REQUIRING SEPARATE WARNING LAMPS &/OR BUZZERS FOR EACH OF THE SERVICE RESERVOIR SYSTEMS. BASED ON OUR REVIEW OF FMVSS NO. 121, & COMPARING IT WITH THE FACTS SURROUNDING THE SUBJECT VEHICLE INVOLVED IN NTSB'S INVESTIGATION, WE BELIEVE THAT THE STANDARD PROVIDES FOR ADEQUATE SAFETY REGARDING LOW-AIR-PRESSURE WARNING AS CURRENTLY WRITTEN. PURSUING A COURSE OF ACTION TO REQUIRE INDEPENDENT LOW-AIR-PRESSURE WARNING SYSTEMS, EITHER THROUGH COOPERATIVE EFFORTS WITH THE SOCIETY OF AUTOMOTIVE ENGINEERS,OR THROUGH A RULEMAKING EFFORT TO AMEND FMVSS NO. 121, DOES NOT APPEAR TO BE APPROPRIATE AT THIS TIME.