Stopper & Associates, LLCStopper & Associates, LLCMotor Carrier Safety / Highway Collision Research & ReconstructionMotor Carrier Safety / Highway Collision Research & Reconstruction

Nationwide Commercial Motor Vehicle InvestigationsNationwide Commercial Motor Vehicle Investigations

Stopper & Associates, LLCStopper & Associates, LLCTruck & Bus Collision InvestigationsTruck & Bus Collision Investigations

Federal Motor Carrier Safety Regulation (FMCSR)Federal Motor Carrier Safety Regulation (FMCSR)& Commercial Drivers License (CDL) compliance& Commercial Drivers License (CDL) compliance

Forensic MappingForensic MappingLaser “Total Station” measurements. “Reflectorless” unit allows detailed scene Laser “Total Station” measurements. “Reflectorless” unit allows detailed scene

diagramming without interference with normal traffic flow. diagramming without interference with normal traffic flow.

Fatal Collision InvolvingFatal Collision Involving2 Chemical Tankers2 Chemical Tankers

Forensic Map with Forensic Map with Reconstruction AnalysisReconstruction Analysis

Rollover – Fatality involving two fuel tankersRollover – Fatality involving two fuel tankers

Forensic mapping of School Bus -Forensic mapping of School Bus -Refuse truck multiple fatalRefuse truck multiple fatal

Forensic mapping of crash vehicle Forensic mapping of crash vehicle & exemplar vehicle& exemplar vehicle

Forensic - Computer Impact Forensic - Computer Impact AnalysisAnalysis

Crash Scene Forensic Mapping &Crash Scene Forensic Mapping &Reconstruction AnalysisReconstruction Analysis

Forensic map / Satellite PhotoForensic map / Satellite PhotoOverlay of Crash SceneOverlay of Crash Scene

Portable Performance Based Brake Testing*Portable Performance Based Brake Testing*Vehicle weight, brake balance, air pressure and brake force testingVehicle weight, brake balance, air pressure and brake force testing

*49 CFR 393.52(a)(4) approved test method*49 CFR 393.52(a)(4) approved test method

PBBT Testing– Transportation Research PBBT Testing– Transportation Research Center (TRC) – East Liberty, OHCenter (TRC) – East Liberty, OH

PBBT TestingPBBT TestingAccident Reconstruction ConferenceAccident Reconstruction Conference

Houston, TXHouston, TX

Stopper & Associates, LLC PBBT - Brake Testing – Stopper & Associates, LLC PBBT - Brake Testing – Bus Involved in Rollover – Multiple FatalitiesBus Involved in Rollover – Multiple Fatalities

New Brunswick, CanadaNew Brunswick, Canada

Commercial Vehicle Brake Testing Commercial Vehicle Brake Testing & Crash Reconstruction Training& Crash Reconstruction Training

Stopper & Associates, LLCStopper & Associates, LLCTraining Law Enforcement & Collision Training Law Enforcement & Collision

Reconstruction Specialists in the USA & CanadaReconstruction Specialists in the USA & Canada

David Stopper holds a CDL for all classes of David Stopper holds a CDL for all classes of Commercial Motor Vehicles and is a registered Commercial Motor Vehicles and is a registered

USDOT Motor CarrierUSDOT Motor Carrier

Stopper & Assoc., LLC Stopper & Assoc., LLC Mobile Forensic Lab & Incident Response UnitMobile Forensic Lab & Incident Response Unit

Fatality involving multiple Fatality involving multiple brake failuresbrake failuresCase StudyCase Study

Investigated by NTSB & Investigated by NTSB & Stopper & Assoc., LLCStopper & Assoc., LLC

National Transportation Safety Board, National Transportation Safety Board, Collision Between Truck-Tractor Collision Between Truck-Tractor Semitrailer and School Bus Near Semitrailer and School Bus Near

Mountainburg, AR on May 31, 2001,Mountainburg, AR on May 31, 2001, NTSB/HAR-02/03; PB2002-916203; NTSB/HAR-02/03; PB2002-916203;

Adopted September 4, 2002. Adopted September 4, 2002.

Air Brake ExaminationAir Brake Examination

Type 30/30 Brake ChamberType 30/30 Brake Chamber& Automatic Slack Adjuster& Automatic Slack Adjuster

Federal Motor CarrierFederal Motor CarrierSafety RegulationsSafety Regulations

49 CFR 393.1 requires CMV maintained to 49 CFR 393.1 requires CMV maintained to applicable standardsapplicable standards

49 CFR 393.53 requires Automatic Brake 49 CFR 393.53 requires Automatic Brake Adjusters on CMVs manufactured on/after Adjusters on CMVs manufactured on/after 10/20/94.10/20/94.

49 CFR 393.55(c)(1) requires ABS on air 49 CFR 393.55(c)(1) requires ABS on air brake truck tractors manufactured on/after brake truck tractors manufactured on/after 3/1/973/1/97

49 CFR 393.55 (c)(2) requires ABS on air 49 CFR 393.55 (c)(2) requires ABS on air brake trucks, buses & trailers brake trucks, buses & trailers manufactured on/after 3/1/98manufactured on/after 3/1/98

Brake adjustment indicator 49 CFR 393.53(c) Brake adjustment indicator 49 CFR 393.53(c)

Air Brake Vehicles Mfg. After 10/20/94Air Brake Vehicles Mfg. After 10/20/94

Type C- 30 (Clamp Type)Type C- 30 (Clamp Type)Air Brake ChamberAir Brake Chamber

Application Force ChartApplication Force Chart

NTSB reported:NTSB reported:

““A broken spring, which is difficult to A broken spring, which is difficult to detect, can reduce emergency-parking detect, can reduce emergency-parking brake forces or render the emergency-brake forces or render the emergency-parking brake inoperable, and the parking brake inoperable, and the broken spring pieces can be displaced, broken spring pieces can be displaced, thus shortening the pushrod stroke or thus shortening the pushrod stroke or preventing the automatic slack adjuster preventing the automatic slack adjuster from functioning. The extent of the from functioning. The extent of the broken spring problem is broken spring problem is undetermined.undetermined.

ConclusionsConclusions

It has become apparent there is a It has become apparent there is a general lack of knowledge as to the general lack of knowledge as to the critical nature of proper installation, critical nature of proper installation, lubrication and periodic inspection of lubrication and periodic inspection of these critical safety devices.these critical safety devices.

ConclusionConclusion

It is very important that collision It is very important that collision investigators and CMV maintenance investigators and CMV maintenance personnel be trained and become personnel be trained and become familiar with the operation and familiar with the operation and critical factors that can render ASA / critical factors that can render ASA / ABAs inoperative leading to ABAs inoperative leading to diminished brake force and/or brake diminished brake force and/or brake failure.failure.

Conspicuity InvestigationsConspicuity Investigations

Stopper & Associates works with Stopper & Associates works with internationally know experts in night internationally know experts in night time & low light visibility crashestime & low light visibility crashes

Worked with motor carriers to install Worked with motor carriers to install retroreflective materials for safety retroreflective materials for safety beforebefore it was required by law it was required by law

Stopper & Associates is unique in its Stopper & Associates is unique in its ability to analyze and measure the ability to analyze and measure the condition of retroreflective surfaces.condition of retroreflective surfaces.

CONSPICUITYCONSPICUITYARE YOU SURE OF WHAT YOU ARE SEEING?ARE YOU SURE OF WHAT YOU ARE SEEING?

CONSPICUITYCONSPICUITY

A MEASURE OF THE LIKELYHOOD A MEASURE OF THE LIKELYHOOD THAT A DRIVER WILL NOTICE A THAT A DRIVER WILL NOTICE A CERTAIN TARGET AT A GIVEN CERTAIN TARGET AT A GIVEN DISTANCE AGAINST A CERTAIN DISTANCE AGAINST A CERTAIN BACKGROUNDBACKGROUND

Ref. NHTSA Driver Performance Ref. NHTSA Driver Performance Data BookData Book

ContrastContrast

The ratio of luminance from a target The ratio of luminance from a target to the luminance from the target’s to the luminance from the target’s surroundingssurroundings

ContrastContrast

The ratio of luminance from a target The ratio of luminance from a target to the luminance from the target’s to the luminance from the target’s surroundingssurroundings

ContrastContrast

The ratio of luminance from a target The ratio of luminance from a target to the luminance from the target’s to the luminance from the target’s surroundingssurroundings

ContrastContrast

The ratio of luminance from a target The ratio of luminance from a target to the luminance from the target’s to the luminance from the target’s surroundingssurroundings

Retroreflective Sheeting on Commercial Motor Vehicles

Duty of Motor Carriers:

49 CFR §393.13. Retroreflective sheeting and reflex reflectors,

requirements for semitrailers and trailers manufactured before December 1, 1993.

Motor carriers operating trailers, other than container chassis (as defined in §393.5),

have until June 1, 2001, to comply with the requirements of this section.

Motor carriers operating container chassis had until December 1, 2001, to comply with the requirements of this section.

FMCSA Recognizes benefits and FMCSA Recognizes benefits and requires a retrofit regulation:requires a retrofit regulation:

Conspicuity IssuesConspicuity IssuesPassenger vehicle vs. semi trailerPassenger vehicle vs. semi trailer

Under ride crashes Under ride crashes (This crash occurred before sunrise)(This crash occurred before sunrise)

David Stopper Measuring Reflectance with Gamma David Stopper Measuring Reflectance with Gamma Scientific Model 922 Retroreflectance Meter Scientific Model 922 Retroreflectance Meter

Fatal Night Trailer Under Ride CrashFatal Night Trailer Under Ride Crash

RETROREFLECTIVE MATERIALRETROREFLECTIVE MATERIALVS REFLEX REFLECTORVS REFLEX REFLECTOR

Refelex reflector – plastic prismRefelex reflector – plastic prism Reflex reflector – fades rapidly to Reflex reflector – fades rapidly to

observer at approximately 20 – 23 observer at approximately 20 – 23 degree angle to light source / observerdegree angle to light source / observer

Retro reflective material wider Retro reflective material wider angularity – drops 50% or more at 45 angularity – drops 50% or more at 45 degree angle to light source / observerdegree angle to light source / observer

Both dependant on radiance or Both dependant on radiance or luminous intensity (brightness) of light luminous intensity (brightness) of light source.source.

Model 922 Retroreflective MeterModel 922 Retroreflective Meter

Retroreflective MaterialsRetroreflective Materials

Many motor carriers combineMany motor carriers combinereflective materials with reflective materials with

advertising as well as the advertising as well as the required red/white pattern required red/white pattern

retroreflective taperetroreflective tape

CONSPICUITYCONSPICUITY

A MEASURE OF THE LIKELYHOOD A MEASURE OF THE LIKELYHOOD THAT A DRIVER WILL NOTICE A THAT A DRIVER WILL NOTICE A CERTAIN TARGET AT A GIVEN CERTAIN TARGET AT A GIVEN DISTANCE AGAINST A CERTAIN DISTANCE AGAINST A CERTAIN BACKGROUNDBACKGROUND

Well maintained retroreflective tape Well maintained retroreflective tape improves safety and has saved livesimproves safety and has saved lives

David A. Stopper Juli R. StopperStopper & Associates, LLCMotor Carrier Safety – Highway Collision Research & ReconstructionWashington, DC Area Office6200 Evergreen Mountain RoadBroad Run, VA 20137540-347-0702 Fax 540-347-0763

Midwest & Southwest Operations – (Direct inquires to VA Office)Texas & Pacific Railroad Building221 W. Lancaster Avenue Suite 11008Fort Worth, TX 76102e-mailMobile: stopperBUS@aol.com Office: stopperTRUCKS@aol.com

For more information on investigations or training:For more information on investigations or training: