FEDERAL HIGHWAY ADMINISTRATION • OFFICE OF MOTOR CARRIERS

FHWA Contact: Taft Kelly, HSA-30, (202) 366-1231 

Risk-based Evaluation of Commercial

Motor Vehicle Roadside Violations:

Process and Results

Introduction

Risk management is the process by which an organization identifies and understands

sources of risk, makes decisions on how to allocate resources to address these risks, and

confirms the validity of these decisions using performance results. The Federal Highway

Administration’s Office of Motor Carriers (OMC) is investigating the use of risk management and risk-based decision-making to enhance agency efforts to promote the safe

operation of commercial motor vehicles (CMVs). 

One way to apply this approach is in the risk-based differentiation of the vehicle, 

driver, and hazardous materials (HM) violations found during roadside inspections of

CMVs. By differentiating between violations that present a high likelihood of being

contributing factors to a crash or HM incident and those violations that are “lower

risk,” OMC can focus government safety and inspection resources on controlling 

violations that present the highest risk of crash, injury, and fatality. As a part of its risk

management efforts, OMC sponsored a risk-based evaluation of roadside violations;

this tech brief summarizes the study final report. 

Purpose

This evaluation sought to categorize each CMV roadside violation according to the

potential risk posed by the conditions covered by the violation. Risk was defined as the

likelihood that a violation will be a contributing factor to a crash or HM release or

exposure. 

The resulting categorization was designed to distinguish among violations that 

contribute to a significant, immediate risk of a crash or HM incident; violations that

pose less significant risks; and violations that pose little or no risk. This categorization

provides information that may: 

• Support OMC decisions regarding allocation of enforcement resources; 

• Support potential changes to vehicle and driver out-of-service criteria; and 

• Provide a basis for numerical weighting of CMV roadside violations in carrier 

evaluation systems. 

Methodology 

The report authors developed a risk-based categorization of CMV roadside violations

through a synthesis of expert knowledge and judgment regarding the risks associated

with different roadside violations. Risk categories were defined according to the potential consequences of the driver, vehicle, and HM violations, and the likelihood that the

Tech Brief

The vision of the Office of

Motor Carriers is to help

move people, goods, and

commercial motor vehicles

on our Nation’s highways in

the most efficient, economical, and crash-free manner

possible. The OMC research

and technology program

focuses on improving safety

in interstate commercial

motor vehicle operations and

serves a trucking and motor

coach industry that carries

more than 40 percent of all

intercity freight.

Studies are conducted in the

following areas: commercial

driver human factors, health,

and performance needs; new

and emerging driver and

vehicle technologies; safetyrelated data collection and

analysis needs; and performance-based changes to the

Federal Motor Carrier Safety

Regulations.

The OMC’s information

analysis research activities

support the collection, 

analysis, application, and 

dissemination of motor 

carrier industry safety data.

Office of Motor Carrier Research

and Standards

400 Seventh Street, SW

HCS-30; Room 3107

Washington, DC 20590
potential consequences would occur. There were five

consequences considered for this evaluation: 

• Motor vehicle crash 

• Injuries and fatalities as a result of a crash 

• Release or spill of hazardous materials, or the 

exposure of hazardous materials to the public or

emergency response personnel 

• Motor vehicle crash and the release, spill, or 

exposure of hazardous materials 

• No crash or hazardous material release, spill, or

exposure 

A qualitative “likelihood scale” was used to stratify

the risk categories, representing different orders of

magnitude for the likelihood that the defined 

consequences would occur, given the existence of a

violation. 

Panels with expertise in CMV safety and representing

diverse viewpoints, were convened to evaluate and

categorize violations for their potential risk. The 

panels included representatives from the industry,

state and local enforcement agencies, and insurance

companies along with representatives from research

organizations, insurance companies and insurance

industry professional organizations, and public safety

advocacy groups. Each panel was asked to categorize

more than 500 driver, vehicle, and HM violations identified by CMV roadside inspection software, ASPEN.

All panel members evaluated the 231 driver and 

vehicle violations identified in ASPEN. Only the first

panel evaluated the 333 HM violations in ASPEN. 

Within each panel, most violations were assigned to

risk-based categories by group consensus. When a

consensus was not reached, the categorization was

based on the majority judgment within the panel.

After the panel meetings, the evaluations by each of

the panels were compared. In those cases in which

the evaluations differed, a categorization was recommended that was consistent with the risk category

consequences and likelihood definitions. 

Results 

The results of the panel evaluations are shown in

tables 1 and 2. Table 1 gives the recommended 

risk-based characterization of the 231 driver and 

vehicle violations and the number of violations in

each category; table 2 presents the recommended 

categorization of the 333 HM violations and the 

number in each category. 

Driver and Vehicle Violations 

The risk-based categorization of driver and vehicle

violations is primarily defined according to the 

significance of the violation as a potential contributing factor in a crash. The results summarized in 

table 1 lead to the following observations: 

The majority of driver or vehicle violations (182 

violations/82 percent) were considered potentially 

significant primary or contributing factors in 

crashes, including: 

• Inoperable head lamps 

Table 1. 

Risk-Based Categorization of Roadside Violations: Driver and Vehicle

Risk Categorization Number of Violations

All Out of Non-Out of

Service Service

Violation is potential single, immediate factor leading to crash 24 18 6

or injuries/fatalities given crash.

Violation is potential single, eventual factor leading to crash 71 40 31

or injuries/fatalities given crash.

Violation is potential contributing factor in crash or injuries/ 87 44 43

fatalities given crash.

Violation is unlikely potential contributing factor in crash or 20 1 19

injuries/fatalities given crash.

Violation has little or no connection to crashes or prevention 21 0 21

of injuries/fatalities.

Note: Eight vehicle and driver violations (four out-of-service violations) were determined to be duplicative of other violations or defined too

vaguely for valid evaluation. These violations were not categorized.
• Inoperative/defective brakes 

• Operating a CMV without a CDL

• Improper or no load securement 

• Power steering violations 

The remaining 18 percent of violations (41 violations)

were considered insignificant as potential contributing factors to crashes, such as: 

• Driver record of duty status not current

• Unauthorized passenger on board 

• Inadequate floor condition 

• Damaged or discolored windshield 

• Tampering with bus heater 

Among this group, 21 violations (9 percent of all 

violations) were considered to have no connection to

crashes or preventing injuries in the event of a crash. 

The majority of driver or vehicle out-of-service 

violations (58 violations/56 percent) were considered

potential factors in a crash with no additional failures

or occurrences needed. Within this group, most violations were not considered an imminent risk of leading

to a crash. The remaining 44 percent of driver or vehicle out-of-service violations (45 violations) were not

considered potential factors leading to crashes unless

occurring with additional failures, deterioration, or

occurrences. These violations were judged to pose a

lower likelihood of leading to a crash than 31 percent

of violations that were not out-of-service violations. 

Hazardous Materials Violations 

The categorization of hazardous materials violations

is defined according to the significance of the violation in potentially contributing to the release or spill

of HM, or the exposure of the public or emergency

response personnel to HM. 

The majority of HM violations (188 violations/58 percent) were considered potentially significant, primary

contributing factors in HM releases or exposure; these

included: 

• Release of HM from package 

• Unauthorized packaging 

• Smoking while loading or unloading 

• Package not secure in vehicle 

• Vehicle not placarded as required 

The remaining 137 HM violations (42 percent) were

not considered likely contributing factors to releases

or exposure, including the following: 

• Total quantity not listed 

• Failed to display duplicate label as required

• Description is not in proper sequence 

• Bulk package marking is incorrect size 

Table 2. 

Risk-Based Categorization of Roadside Violations: Hazardous Materials

Risk Categorization Number of Violations

All Out of Non-Out of

Service Service

Violation is potential single, immediate factor leading to 13 1 12

hazardous materials release or exposure.

Violation is potential single, eventual factor leading to 57 5 52

hazardous materials release or exposure.

Violation is potential contributing factor in hazardous materials 118 10 108

release or exposure.

Violation is unlikely potential contributing factor in hazardous 54 0 54

materials release or exposure.

Violation has little or no connection to hazardous materials 83 3 80

release or exposure.

Note: Eight hazardous materials violations (two out-of-service violations) were determined to be duplicative of other violations or defined too

vaguely for valid evaluation. These violations were not categorized.
Researcher

This study was performed by

Cycla Corporation, 12109

Drews Ct., Potomac, MD,

20854, Telephone: (301) 990-

9604, Contract No. DTFH61-95-

Z-00110.

Distribution

This Tech Brief is being distributed according to a standard

distribution. Direct distribution

is being made to the Resource

Centers and Divisions.

Availability

The study final report is 

available by contacting Taft

Kelly, HSA-30, (202) 366- 1231.

Key Words

risk management, risk-based

categorization, ASPEN, 

risk-based numerical weights,

likelihood, risk assessment, 

consequence.

Notice

This Tech Brief is disseminated

under the sponsorship of the

Department of Transportation

in the interest of information

exchange. The Tech Brief 

provides a synopsis of the

study’s final publication. The

Tech Brief does not establish

policies or regulations, nor

does it imply FHWA endorsement of the conclusions or 

recommendations. The U.S.

Government assumes no 

liability for its contents or 

their use.

• Exemption number not listed 

A significant number of HM violations (83 violations/ 26 percent) were considered to

have little or no effect on the potential for a release or exposure. The majority of HM

out-of-service violations (13 violations/ 68 percent) were not considered to be potential

factors in releases or exposures unless they occur in conjunction with additional failures, deterioration, or other events. These violations were considered to be less likely

to lead to the release or exposure of HM than 21 percent of violations that are not

out-of-service violations. Three HM out-of-service violations were judged to have little

or no effect on the potential for release or exposure. 

Conclusions

The results of the roadside evaluation and the risk-based categorization of CMV 

violations indicate significant differences in the level of risk associated with different

violations and provide the basis for several conclusions. 

The categorization of CMV violations provides information to assist enforcement 

personnel in setting priorities among items to inspect. This evaluation suggests that

violations considered “low-risk” should be examined to assess if these violations should

remain important parts of the Federal Motor Carrier Safety Regulations (FMCSR) or

Hazardous Materials Regulations (HMR). In addition, many violations represent a broad

range of risk levels, depending upon the severity of the conditions that warrant the

violation. These violations could be broken down further; the conditions posing 

different levels of risk could be evaluated and categorized separately. Researchers also

recommend that out-of-service violations that were judged not to involve significant

immediate risks be examined further to determine if they should remain as part of the

out-of-service criteria. 

While OMC is a data-driven organization, the lack of detailed crash causation data

forces the agency to rely on its knowledge and logic, rather than directly applicable

data on crashes associated with specific roadside violations. The evaluation of crash 

risk requires both science and judgment. Researchers believe that the use of expert

knowledge and judgment in the risk-based categorization of CMV violations constitutes a resource for making future decisions about changes to the FMCSRs, HMRs, and

out-of-service criteria. These changes could lead to an efficient use of scarce regulatory

and enforcement resources, while minimizing the risk of crashes and HM incidents. 

Finally, the risk-based categorization of roadside violations may provide a basis for

assigning numerical weights to violations as part of carrier evaluation and selection 

systems. The assigned weight for each violation would be proportional to the level of

risk represented by the category assigned in the evaluation process. The risk categories

defined for violations would represent decreasing orders of magnitude of risk. 

Risk management provides OMC with a process by which agency resources may be

rationally allocated so that they focus on the most important issues affecting industry

performance. This approach could help to assure the optimal use of agency resources

by potentially providing a logical, structured, and defensible mechanism by which 

OMC can evaluate the relative significance of each candidate activity in relation to the

maximum national safety benefit it supports. OMC is continuing to explore ways in

which risk management can be used to improve agency performance. 

Currently OMC is investigating three areas of risk management application: agenda

management; planning and resource allocation; and supporting changes to the 

FMCSRs and HMRs.

January 1999

Publication No. FHWA-MCRT-99-005