FEDERAL HIGHWAY ADMINISTRATION • OFFICE OF MOTOR CARRIERS

FHWA Contact: Robert Davis, HCS-30, (202) 366-2997

Commercial Driver Rest & Parking

Requirements: Making Space for

Safety

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 human factors

research projects aim to 

promote alert, healthy 

drivers and seek to improve

the uniformity and effectiveness of driver training and

licensing.

Office of Motor Carrier Research

and Standards

400 Seventh Street, SW

HCS-30; Room 3107

Washington, DC 20590

Introduction

The ability of commercial motor vehicle operators to safely stop and rest is a special

concern to commercial motor vehicle transportation. This Tech Brief presents a Federal

Highway Administration study that addressed the adequacy of both public and private

parking facilities nationwide. More information about this study can be found in a 

separate report (FHWA-MC-96-0010) of the same title.

Purpose

The steady growth in trucking nationwide appears to have increased the demand for

rest areas along the nation’s highways. Commercial drivers need a safe place to park,

especially at night, to maintain their alertness. A growing concern about commercial 

driver fatigue has created a need to assure public safety along the highways.

The primary goal of this study was to consider parking statutes and enforcement, and 

to determine the supply, utilization, and demand for truck parking at both rest areas

(public facilities) and truck stops (privately-owned facilities). Researchers sought to

address a perceived need for additional parking space through direct observation,

interviews, statistical sampling and evaluations, modeling, and demographic data 

collection.

Research Methodology

Prior rest area research has typically concentrated on analyzing data at the individual

Interstate corridor level. In order to undertake empirical research at the state and

national level, this study generated the first nationwide inventory of public rest areas

along Interstate highways, as well as projections of parking area availability and

demand at public rest areas and privately-owned truck stops.

The initial phase of the research concentrated on the current status of public rest area

parking for trucks. Researchers relied on three general methods of data collection:

• An inventory of parking capacity and restrictions at 1,487 public rest areas in the 

48 contiguous states.

• Direct observation of the actual use of truck parking at facilities along a mediumdensity trucking corridor. Researchers collected information through peak-period 

surveillance of truck parking activities along a 200-mile segment of I-81 from

Radford, Virginia to Knoxville, Tennessee.

• A series of interviews and surveys that consulted 500 truck drivers, 330 motor 

carriers, and 170 truck stop operators.
Upon completion of the public rest area portion of 

the study, a second survey was conducted to assess

the supply and demand for parking at privatelyowned truck stops. Researchers mailed survey 

questionnaires to 987 members of the National

Association of Truck Stop Operators in order to obtain

feedback from a representative sample of truck stop

operators nationwide. Responses were received from

381, or 39 percent, of them, providing information on

truck parking capacity, usage, and space availability.

Drawing on other information about privately-owned

truck stop distribution in the U.S., the contractor

determined that those responding to the questionnaire were primarily large facilities (80 or more 

parking spaces) and tended to represent some 

areas of the nation more extensively than others.

Therefore, researchers used statistical weighting 

procedures to adjust these deviations in both size and

regional distribution to ensure that the final survey

results could be accurately projected to the total 

target population.

Models 

This research led to the development and testing of

two models to analyze public rest area usage by truck

drivers and the need for additional

truck parking spaces at rest areas

along the Interstates.

The Capacity Utilization Model identified the services and facilities that

affect the utilization of truck parking

at public rest areas, as illustrated in

Figure 1. Using data from 709 rest

areas located across the country, this

model estimated the individual

impact of variables that affect the 

utilization of parking spaces, such 

as: distance from the previous rest area; one-way

average daily traffic; number and type of available

parking spaces; and the presence of picnic tables,

vending machines, telephones, and repair facilities. 

The Truck Parking Demand Model estimated the

nationwide demand for truck parking spaces at

public rest areas. It was based on a modification of a

mathematical model developed by the Minnesota

Department of Transportation (MnDOT) in 1979. The

original MnDOT model was based on data collected at

Minnesota Interstate rest areas; this modified version

applied the same analytical framework on a national

level. The new version also incorporated guidelines

presented in a 1994 Virginia Department of

Transportation study of rest area usage.

The modifications made to the MnDOT model 

included:

• Adding controls for design hour ratio assumption 

for average daily traffic figures exceeding 30,000

vehicles.

• Increasing the percentage of mainline traffic 

entering a rest area that has attributes found by

the Capacity Utilization Model to increase utilization of truck parking. These include food facilities,

proper lighting, distance from the previous rest

area, and diagonal, pullthrough parking.

• Decreasing the vehicles-per-hour space assumption

to reflect longer truck parking time, indicating an

average parking time per space of 30 minutes

instead of 20 minutes. 

Findings

This research documented some important distinctions between public rest areas and privately-owned

truck stops. Rest areas on Interstate highways are 

easily accessible on the right-of-way and provide

parking for automobile and truck drivers, as well as

rest rooms and vending machines. Most truck stops

Capacity

Utilization

Model

UTILIZATION FACTOR

Traffic Volume

Number and Type of spaces

Facilities (e.g. vending machines,

repair facilities, picnic tables)

Distance to next rest area

or intersection

PREDICTION

OF USE

Figure 1.

Table 1. 

Types of Truck Parking Services Provided by

Privately-Owned Truck Stops (Weighted Base)

Free Truck Parking 94 %

Lighted Parking 92 %

Paved Parking 86 %

Marked Parking Spaces 55 %

Secured at Night 18 %

Able to Accommodate 73 %

Non-Standard Trucks

Oversized Trucks 71 %

Triples 51 %

Hazmat Trucks 30 %
are located close to Interstate ramps and provide 

services such as fuel, showers, sleeping quarters, and

restaurants, in addition to parking space. Differences

in the services provided contribute significantly to

truck drivers’ decisions about where and how long to

stop. Table 1 presents the types of services many 

privately-owned truck stops provide. 

Public Rest Area Evaluation

Researchers first inventoried 1,487 public rest areas

with facilities on the Interstate highway system. 

Then they conducted a direct observation survey

along a medium-density Interstate corridor to 

measure current capacity and demand for short-term

(less than 2 hours) and long-term truck parking.

Researchers found:

• Of the approximately 576 spaces designated for

truck parking at the 7 sites along the observed

Interstate corridor, only 20 percent were in public

rest areas. The rest were in privately-owned truck

stops. 

• During the day, half of the rest areas inventoried

were full or overflowing; 8 in 10 were full or 

overflowing at night. 

• Few legal spaces were available at rest areas

between midnight and 5 a.m. Rest areas reached

capacity before truck stops.

• Trucks often park on Interstate shoulders and ramps

to avoid parallel parking spaces that some drivers

indicated were difficult to use. 

• Truck parking capacity at rest areas was reduced by

recreational vehicles and cars parked in truck 

parking areas. Poor designs that caused trucks to

park across more than one space also reduced

capacity. It was evident that diagonal, pullthrough

parking spaces are the most efficient.

• Approximately 42 percent of the 1,487 rest areas

have a time limit on truck parking, but only 1 in 10

of these facilities report that the limits are “always”

enforced.

Surveys and interviews with truck drivers, motor 

carrier executives, and truck stop operators generated

information about the needs, habits, opinions, and

preferences of truck drivers. Most truck drivers and

motor carriers believe there is a shortage of adequate

long-term or overnight parking facilities for truckers.

Survey results also indicated that truck drivers prefer

privately-owned truck stops for long-term or

overnight parking. The majority of truck drivers and

motor carriers rated truck stops favorably, citing more

room to park, availability of food, cleanliness, and

feelings of safety and security. However, truck drivers

are more likely to use rest areas for short-term stops;

those who prefer rest areas report that accessibility is

the most important factor in choosing a short-term

parking space.

Private Truck Stop Evaluation

The surveys and direct observation of truck drivers,

motor carriers and truck stop operators indicated that

privately-owned facilities might offer a means to 

satisfy the shortage of parking spaces at public rest

areas, especially at night. The weighted sample 

generated by the private truck stop study was used 

to project a national picture of truck stop capability

to meet demand.

The majority of truck stop operators reported that

their parking facilities were full or overflowing at

night. Over half were filled to capacity 20 nights per

month or more. The weighted sample projected an

average of 167,000 trucks to be parked at private

truck stops in the target population on any given

night. This accounted for only 84 percent of the total

projected capacity (185,000) of truck parking provided

by truck stops along the Interstate highway system

nationwide. Even though many truck stops were

reportedly filled to capacity at night, this study 

indicated an overall surplus in parking spaces at 

privately-owned facilities.

The assessment also determined that about one-third

of truck stop operators plan to expand their parking

facilities over the next 3 years. This would increase

the total projected parking capacity by 15 percent,

from the current 185,000 spaces to more than

213,000.

Database Limitations

The objective of the truck stop study was to extend

the rest area study research effort by including data

on private facilities. One research goal was to merge

Aerial view of diagonal, pullthrough truck parking

facilities.
Researcher

This study was performed by

the Trucking Research Institute,

2200 Mill Road, Alexandria, VA

22314, Telephone: (703) 838-

1966. Contract No. DTFH61-92-

C-00092.

Distribution

This Tech Brief is being 

distributed according to a 

standard distribution. Direct

distribution is being made to

the Regions and Divisions.

Availability

The study final report (PB97-

124705) is available from the

National Technical Information

Service, Telephone: (703) 605-

6000.

Key Words

safety, rest area, parking, truck

stop, fatigue, commercial 

vehicle safety, highway safety.

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.

August 1998

Publication No. FHWA-MCRT-98-002

the data collected on truck stops with the existing data on public rest areas to create a

unified database that could define both public and private availability and needs. This

would be especially relevant for evaluating the impact of excess parking at truck stops

on rest area parking needs. Unfortunately, the differences in the two databases, 

including sample size and geographical factors, prevented the development of a single

database.

Substitutability

If public rest areas and privately-owned truck stops are not direct substitutes for each

other, then the existence of a shortfall in rest area parking cannot be absorbed by the

presence of excess parking spaces at truck stops. The findings and analyses of the 

evaluations of the two types of facilities offer certain insights as to whether or not the

facilities are interchangeable. These include:

• The direct observation of private truck stops and public rest areas indicated that

truck drivers tend to use rest areas for their short-term parking needs, and truck

stops for long-term parking needs.

• Significant differences exist in the range of services offered by the two types of 

parking facilities; truck stops typically offer a wider range of services than rest areas.

• Based on driver survey results, accessibility to parking facilities had some influence 

on driver choice of a place to stop. Drivers who value accessibility tended to prefer

public rest areas.

• Statistical findings indicated that safety features were positive attributes in 

explaining capacity utilization of truck parking spaces, and a major reason why 

drivers prefer truck stops.

Based on the information collected and the analytical findings of the study, there was

no conclusive evidence that public rest areas and privately-owned truck stops are direct

substitutes for each other. Rather, they are complementary, since drivers utilize the two

types of facilities for different reasons. As determined by this research, the apparent

shortfall of truck parking spaces nationwide continues to a problem for creative solution by both the public and the private sectors.

Recommendations

The options for expanding truck parking in rest areas nationwide vary substantially in

cost, required engineering, administrative responsibilities, and the number of 

additional parking spaces they may create. The study classified options in four 

categories: enforcement, modification, renovation, and new construction.

Researchers recommended that the most cost effective way to increase the number of

parking spaces to meet current parking requirements is to renovate existing facilities

and, where necessary, build new facilities. Researchers also recommended that a public

policy approach be developed by state and local officials to analyze current spending

practices and integrate truck parking requirements.

Future Research

Subsequent research in this area is under consideration. In the Transportation Equity

Act for the 21st Century, Congress mandated a further study to determine the location

and quantity of parking spaces at public rest areas and private rest stops along the

National Highway System. The study will include an analysis of projected parking 

shortages and a plan to reduce or eliminate the shortages. A National Conference on

Safety Rest Area Support is also being organized. This conference will bring together

interested parties to discuss effective means to increase safe, off-road parking.