Santa Monica, CaliforniaJuly 16, 2003

Highway Accident Report

NTSB/HAR-04/04PB2004-916204Notation 7649B

National TransportationSafety Board

Washington, D.C.

Highway Accident Report

Rear-End Collision and Subsequent Vehicle Intrusion 

Into Pedestrian Space at Certified Farmers’ Market 

Santa Monica, California

July 16, 2003

NTSB/HAR-04/04

PB2004-916204 National Transportation Safety Board

Notation 7649B 490 L’Enfant Plaza, S.W.

Adopted August 3, 2004 Washington, D.C. 20594
National Transportation Safety Board. 2004. Rear-End Collision and Subsequent Vehicle Intrusion

Into Pedestrian Space at Certified Farmers’ Market, Santa Monica, California, July 16, 2003.

Highway Accident Report NTSB/HAR-04/04. Washington, DC.

Abstract: On July 16, 2003, a 1992 Buick LeSabre was westbound on Arizona Avenue, approaching the

intersection of Fourth Street, in Santa Monica, California. A 2003 Mercedes Benz S430 sedan was stopped

on Arizona Avenue at the intersection for pedestrians in a crosswalk on Fourth Street. The Buick struck the

Mercedes, continued through the intersection, and drove through a farmers’ market, striking pedestrians

and vendor displays before coming to rest. As a result of the accident, 10 people were fatally injured, and

63 people received injuries ranging from minor to serious. The Buick driver and both Mercedes occupants

were uninjured.

The major safety issues discussed in this report are the unintended acceleration of the accident vehicle, the

adequacy of temporary traffic control measures for the protection of pedestrian traffic in the Santa Monica

Certified Farmers’ Market, and the need to equip motor vehicles with event data recorders.

As a result of its investigation, the Safety Board made recommendations to the Federal Highway

Administration, the National Highway Traffic Safety Administration, and the city of Santa Monica.

The National Transportation Safety Board is an independent Federal agency dedicated to promoting aviation, railroad, highway, marine,

pipeline, and hazardous materials safety. Established in 1967, the agency is mandated by Congress through the Independent Safety Board

Act of 1974 to investigate transportation accidents, determine the probable causes of the accidents, issue safety recommendations, study

transportation safety issues, and evaluate the safety effectiveness of government agencies involved in transportation. The Safety Board

makes public its actions and decisions through accident reports, safety studies, special investigation reports, safety recommendations, and

statistical reviews.

Recent publications are available in their entirety on the Web at <http://www.ntsb.gov>. Other information about available publications also

may be obtained from the Web site or by contacting:

National Transportation Safety Board

Public Inquiries Section, RE-51

490 L’Enfant Plaza, S.W.

Washington, D.C. 20594

(800) 877-6799 or (202) 314-6551

Safety Board publications may be purchased, by individual copy or by subscription, from the National Technical Information Service. To

purchase this publication, order report number PB2004-916204 from:

National Technical Information Service

5285 Port Royal Road

Springfield, Virginia 22161

(800) 553-6847 or (703) 605-6000

The Independent Safety Board Act, as codified at 49 U.S.C. Section 1154(b), precludes the admission into evidence or use of Board reports

related to an incident or accident in a civil action for damages resulting from a matter mentioned in the report. 
iii Highway Accident Report

Contents

Acronyms and Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v

Executive Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi

Factual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Accident Narrative . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

Injuries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Meteorological Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Driver Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Accident History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Experience and Local Knowledge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

Preaccident Activities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Postaccident Toxicological Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Medical History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Vehicle and Wreckage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Vehicle Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Accident-Related Damage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

Highway Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Highway Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Traffic Volume and Accident History . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Traffic Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Traffic Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Traffic Control at Service Alley . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Third Street Promenade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Emergency Response . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

Operational Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

History of Farmers’ Markets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

City of Santa Monica . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

Community Event Permitting Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Other Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Manual on Uniform Traffic Control Devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Roadside Design Guide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Caltrans Traffic Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

WATCH Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Bourbon Street Promenade, New Orleans, Louisiana . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Unintended Acceleration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Highway Vehicle Event Data Recorders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Exclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

Unintended Acceleration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

Inadvertent Activation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

Error Detection and Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

Adequacy of Temporary Traffic Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

Event Data Recorders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Contents iv Highway Accident Report

Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Findings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48

Probable Cause . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49

Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50

Appendix A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51

Investigation and Public Hearing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
v Highway Accident Report

Acronyms and Abbreviations

AASHTO American Association of State Highway and Transportation 

Officials

CCFD Culver City Fire Department

CDMV California Department of Motor Vehicles

CFM certified farmers’ market

CFR Code of Federal Regulations

CHP California Highway Patrol

CTM Caltrans Traffic Manual

ECM electronic control module

EDR event data recorder

GVWR gross vehicle weight rating

IC incident commander

IEEE Institute of Electrical and Electronics Engineers

LACFD Los Angeles County Fire Department

LAFD Los Angeles City Fire Department

MCI multi-casualty incident

MUTCD Manual on Uniform Traffic Control Devices

NHTSA National Highway Traffic Safety Administration

NPRM notice of proposed rulemaking

SAE Society of Automotive Engineers

SMCFM Santa Monica Certified Farmers’ Market

SMFD Santa Monica Fire Department

SMPD Santa Monica Police Department

TA typical application

USDA U. S. Department of Agriculture

WATCH Work Area Traffic Control Handbook
vi Highway Accident Report

Executive Summary

On July 16, 2003, about 1:46 p.m. Pacific daylight time, a 1992 Buick LeSabre,

driven by an 86-year-old male, was westbound on Arizona Avenue, approaching the

intersection of Fourth Street, in Santa Monica, Los Angeles County, California. At the

same time, a 2003 Mercedes Benz S430 sedan, occupied by a driver and front-seat

passenger, was also westbound on Arizona Avenue and had stopped for pedestrians in a

crosswalk on Fourth Street at the intersection with Arizona Avenue. The Buick struck the

left rear corner of the Mercedes, continued through the intersection, and drove through a

farmers’ market, striking pedestrians and vendor displays before coming to rest. As a

result of the accident, 10 people were fatally injured, and 63 people received injuries

ranging from minor to serious. The Buick driver and both Mercedes occupants were

uninjured.

The National Transportation Safety Board determined that the probable cause of

this accident was the failure of the Buick driver to maintain control of his vehicle due to

his unintended acceleration. Contributing to the severity of the accident was the lack of a

barrier system to protect pedestrians in the Santa Monica Certified Farmers’ Market area

from errant vehicles. 

The major safety issues discussed in this report are the unintended acceleration of

the accident vehicle, the adequacy of temporary traffic control measures for the protection

of pedestrian traffic in the Santa Monica Certified Farmers’ Market, and the need to equip

motor vehicles with event data recorders.

As a result of its investigation, the Safety Board made recommendations to the

Federal Highway Administration, the National Highway Traffic Safety Administration,

and the city of Santa Monica.
1 Highway Accident Report

Factual

Accident Narrative

On July 16, 2003, about 1:46 p.m. Pacific daylight time, a 1992 Buick LeSabre

(Buick), driven by an 86-year-old male, was westbound on Arizona Avenue, approaching

the intersection of Fourth Street, in Santa Monica, Los Angeles County, California. At the

same time, a 2003 Mercedes Benz S430 sedan (Mercedes), occupied by a driver and frontseat passenger, was also westbound on Arizona Avenue and had stopped for pedestrians in

a crosswalk on Fourth Street at the intersection with Arizona Avenue. The Buick struck

the left rear corner of the Mercedes, continued through the intersection, and drove through

a farmers’ market, striking pedestrians and vendor displays before coming to rest.

The accident occurred moments after the Buick driver had departed the Santa

Monica Main Post Office on Fifth Street. The Buick driver told police investigators that he

could see the farmers’ market as he turned from Fifth Street onto Arizona Avenue.

According to witnesses, the Buick approached the Fourth Street intersection; the

Mercedes had stopped at the red light, had begun to proceed after the light turned green,

and had again stopped to allow pedestrians in the crosswalk to cross Fourth Street. The

Buick then struck the stopped Mercedes in the left rear, pushing it into the intersection.

Witnesses stated that the Buick continued on Arizona Avenue, where it maneuvered past

an orange ROAD CLOSED AHEAD sign on the yellow centerline of the roadway,

through barricades, and into the area where the Santa Monica Certified Farmers’ Market

(SMCFM) had been set up. (See figures 1 and 2.)

The Buick proceeded through the farmers’ market for approximately 2 1/2 blocks

(750 feet) and came to rest on Arizona Avenue near the alley east of the intersection of

Ocean and Arizona Avenues. As a result of the accident, 10 people were fatally injured,

and 63 people sustained injuries ranging from minor to serious. The Buick driver and both

Mercedes occupants were uninjured.

The Mercedes driver characterized vehicular traffic in the area as “moderate” and

pedestrian traffic as “heavy” due to the farmers’ market. In a statement to police, she

described the Buick’s impact to the left rear of her vehicle. The driver stated that she saw

the sign indicating that Arizona Avenue was closed ahead, so she slowed to a stop at the

red light and prepared to make a right turn onto Fourth Street. As the light turned green,

she said she began to proceed, but stopped short of the east-west crosswalk, yielding to

pedestrian traffic. At that point, she felt a sudden impact to the left rear of her vehicle, as

the Buick pushed it forward into the intersection. The Mercedes driver stated that she

looked in her rear-view mirror and saw a maroon-colored car (the Buick) “turn to the left

and accelerate around” her vehicle and then around the ROAD CLOSED AHEAD sign.

She described the acceleration of the Buick as rapid and very loud and said that the vehicle

swerved, then straightened out, and continued to increase its speed as it entered the

farmers’ market. 
Factual 2 Highway Accident Report

Figure 1. Accident area.

Arizona Avenue

Post office

Buick driver's

residence area

Accident site

Santa Monica Boulevard

Wilshire Boulevard

2nd Street

3rd Street

4th Street

5th Street

Ocean Avenue

10

10

N
Factual 3 Highway Accident Report

Figure 2. Aerial view of accident site.
Factual 4 Highway Accident Report

Several witnesses also stated that the accident driver accelerated after striking the

Mercedes, and they characterized the incident as a “hit-and-run” accident. One witness

told police investigators that, from his vantage point on the south side of Arizona Avenue

at Fourth Street, he observed no brake lights on the Buick. A vendor, who observed the

driver as he proceeded through the farmers’ market, told Safety Board investigators that

he saw the Buick driver with both hands on the steering wheel at the 10- and 2-o’clock

positions, looking straight ahead.

Other witnesses described to police investigators the vehicle’s movements through the

market area as alternating between accelerating and decelerating, sometimes at high engine

RPMs, as if the driver “were pressing the accelerator pedal firmly.” The driver himself told

police investigators that he sensed the car accelerate three or four times as he proceeded

through the farmers’ market. One witness concurred with reports of hearing high engine

RPMs, but noted a “slight hesitation” of the engine. According to another witness, it appeared

that every time the Buick struck an object in its path, the vehicle accelerated in response.

The Buick driver stated to police that he tried to stop the car as it went through the

market, stepping on the brake, taking his foot off the accelerator, and ultimately trying to

put the car’s transmission in “park.” He indicated that he might have confused the brake

and accelerator pedals. The accident driver believed that he was also making steering

inputs in an effort to avoid pedestrians and other objects. He was unsure why the car

finally stopped, but thought that he might have succeeded in shifting the transmission into

“park.” In his statement to police investigators, the driver did not recall striking the Mercedes.

Injuries

Ten pedestrians sustained multiple blunt force or traumatic injuries that proved

fatal. Of the 63 people who were injured, 18 pedestrians were seriously injured and 45

sustained minor injuries. An undetermined number of pedestrians present at the farmers’

market reported no injuries.

Table 1. Injury codes.1

Injuries Drivers and passengers Pedestrians Total

Fatal 0 10 10

Serious 0 18 18

Minor 0 45 45

None 3 unknown 3

Total 3 73* 76*

*Excludes “unknown” number of uninjured pedestrians.
Factual 5 Highway Accident Report

Meteorological Information

At the time of the accident, the day was clear, and the roadway was dry. Winds were

from the southeast (220o) at 12 mph. According to the official National Weather Service

report for Santa Monica at 1:51 p.m., the temperature was 78o F, and the dew point was

67o F. Sun transit time (the point at which the sun appears directly overhead) was 1:00 p.m.

Driver Information

The 86-year-old driver held a valid class C (noncommercial) California driver’s

license with a corrective lens restriction, issued on November 28, 2000, and valid for 5

years. He was issued a disabled parking placard in 1994 due to “severe hip arthritis” and

associated limitations in mobility; it had been renewed biannually and was valid at the

time of the accident. Several witnesses told police investigators that the driver was

wearing eyeglasses at the time of the accident. In California, drivers 70 years of age and

older must renew their license in person.2

 

To renew his license, the driver was required to present the renewal notice or

complete an application; permit a thumb print and photograph to be taken for

identification; pay a $15 fee; and pass both a vision examination and a written test of

traffic laws and signs. A road test is generally not required of California drivers 70 years

of age and older who are renewing their licenses, and the driver stated to police that he did

not have to take a road test when he renewed his license in 2000. Drivers must have visual

acuity of 20/40 or better in each eye and in both eyes together, to pass the vision

examination. If corrective lenses are used at the time of testing, the license carries a

corrective lens restriction. The written test comprises 18 multiple-choice questions; drivers

must answer at least 15 correctly to pass and may retake the test as many as three times.

Accident History

The Buick driver had no moving violations prior to the accident; the California

Department of Motor Vehicles (CDMV) revoked his license on July 21, 2003, following

the accident, for “lack of knowledge or skill.” On January 5, 2004, he was charged with 10

counts of vehicular manslaughter with gross negligence; he entered a plea of “not guilty”

to the charges on January 6. 

1 Title 49 Code of Federal Regulations (CFR) 830.2 defines a fatal injury as any injury that results in

death within 30 days of the accident. It defines a serious injury as an injury that requires hospitalization for

more than 48 hours, commencing within 7 days from the date the injury was received; results in a fracture of

any bone (except simple fractures of the fingers, toes, or nose); causes severe hemorrhages, nerve, muscle,

or tendon damage; involves any internal organ; or involves second or third degree burns, or any burns

affecting more than 5 percent of the body surface.

2 See California Department of Motor Vehicles Web site <http://www.dmv.ca.gov/dl/dl.htm>.
Factual 6 Highway Accident Report

Insurance records indicate that the driver had been involved in two previous

incidents, but was not cited, and neither one was reported to the CDMV.3

 In November

1998, he struck an unattended, parked vehicle, causing approximately $200 in damage.

According to the owner of the parked vehicle, the driver struck the right front corner of her

automobile three or four times with his front bumper at low speeds. Insurance records

indicate that she told police the driver was apparently unaware that he was striking her

vehicle as he maneuvered fore and aft, in an attempt to park his own vehicle.

In the other accident, which occurred in September 1999, the driver was traveling

southbound on 14th Street approaching Wilshire Boulevard in Santa Monica, when the

right side of his vehicle was struck by another car, as the driver of that vehicle was

backing out of a parking lot. 

During its investigation of the 2003 accident, the Santa Monica Police Department

(SMPD) learned of another incident involving the driver, which occurred in September

1993. A witness to the 1993 accident provided the SMPD with a videotape of a minor

collision with a retaining wall, which took place when the driver was backing down a

driveway (not his own) in Montecito, California.

Experience and Local Knowledge

The driver had lived in the Los Angeles area for more than 70 years and had

owned the accident vehicle for more than 10 years. The driver stated that he had not

patronized the SMCFM in 3 or 4 years, but was familiar with its location. He told police

that he saw the market when he turned right from Fifth Street and that he saw the

barricades in the roadway before he struck them.

In interviews conducted by Safety Board investigators, the driver’s neighbors said

they were “surprised” to learn of the driver’s involvement in the accident at the farmers’

market and stated that the driver had never exhibited any erratic or unsafe behavior during

the time they had known him. Neighbors noted that the driver used a cane, but were

unaware of any medical problems or prior crashes involving the driver. 

One woman, who had been a neighbor for 30 years, stated that she saw the driver

almost daily and spoke with him about once a week. She described the driver as “friendly”

and “intelligent.” She characterized him as a safe driver who never drove too fast, based

on her observations of him in the neighborhood. 

A neighboring couple first met the driver when they moved into the neighborhood

about 2 1/2 years earlier. They told investigators that they spoke with the driver two or

three times weekly and saw him walking around the neighborhood regularly. They

described the driver as “clear” and “coherent” and said they had observed no indication

that he was either physically or mentally unfit to drive.

3 Section 16000 of the California Vehicle Code requires that all drivers (irrespective of “fault”) file a

report with the CDMV when they are involved in an accident that results in more than $750 in property

damage ($500 for accidents prior to January 1, 2003). The September 1999 incident met the reporting

threshold requirements.
Factual 7 Highway Accident Report

Preaccident Activities

Investigators derived the following information about the driver’s activities before

the accident from the SMPD’s postaccident interviews with the driver and his wife. The

driver said he awoke between 7:00 a.m. and 7:30 a.m. on the morning of the accident, after

a “normal night of sleep,” showered, and read the newspaper. He had breakfast about

10:00 a.m. and shortly after 11:15 a.m., left his house to run some errands. The driver told

police that he returned home about noon, had lunch, and watched television as he finished

writing a letter. Shortly after 1:00 p.m., he again left his house to deliver the letter to the

post office at 1248 Fifth Street (near the intersection with Arizona Avenue), where he

deposited it in the curbside mailbox. The driver told SMPD investigators that he stopped

at the curbside mailbox, put the transmission in “park,” and reached out the passenger-side

window to drop the letter in the receptacle. He said he then departed the post office and

turned onto Arizona Avenue. 

Postaccident Toxicological Testing

After the accident, SMPD officers took the driver to the University of California—

Los Angeles Medical Center in Santa Monica, where blood was drawn from him at 2:40

p.m. The Los Angeles County Sheriff’s Department Scientific Services Bureau tested the

blood sample for alcohol, amphetamines, barbiturates, benzodiazepines, cannabinoids,

cocaine, opiates, and phencyclidine; the results were negative. The Department of Justice

Bureau of Forensic Services conducted additional testing for prescription medications,

which confirmed the presence of quinine.

Medical History

The Safety Board reviewed the driver’s medical records from seven physicians, a

healthcare facility, and two other healthcare service providers. The records showed no

other referrals or indications of treatment by additional providers. 

The following medical conditions were noted: bilateral hip replacements in 1993

(right) and 1998 (left); pain in the right thigh (2000), diagnosed as spinal stenosis;4

 and

lumbar arthritis. In the most recent entries (during 2001), the orthopedic surgeon noted

that the driver’s hips were “stable and exhibit[ed] little contracture.”5

 The records did not

indicate any episodes of seizures, cognitive dysfunction, or loss of consciousness.

A cardiologist examined the driver about 3 weeks after the accident and diagnosed

significant atrioventricular node disease. The driver was subsequently implanted with a

dual chamber pacemaker. According to the cardiologist’s records, the driver had no prior

cardiovascular history other than high cholesterol, and the driver denied having any

symptoms prior to the diagnosis, including light-headedness, near syncope (fainting), or

syncope.

4 Spinal stenosis is a narrowing of the spinal canal. The driver’s physician noted that the driver was

able to walk a mile. No further indication of symptoms was found.

5 Contracture is a permanent muscular shortening due to tonic spasm or fibrosis or to loss of muscular

equilibrium.
Factual 8 Highway Accident Report

The driver walked with a cane. In an interview with police, he stated that he “loses

his cane twice a week” and noted that a person who “really needs a cane never loses his.”

The driver denied any problem sensing or distinguishing the accelerator and brake pedals

and stated that his only problem as a result of hip replacement surgeries was that he walks

with a minor limp. The driver denied any problems with the function of his legs. 

The Safety Board reviewed the driver’s medical records, including those from

local pharmacies. The driver had not been prescribed any psychoactive medications,

which affect the mind, mood, or mental processes, and no evidence of prescriptions

beyond those listed in the records was found.

Vehicle and Wreckage

Vehicle Information

The 1992 Buick LeSabre was manufactured by General Motors at its Flint,

Michigan, plant in January 1992. The Buick was of unibody construction and had a gross

vehicle weight rating (GVWR) of 4,573 pounds and a curb weight of 3,456 pounds.6 The

odometer registered 67,026 miles at the time of postaccident inspection.

The Buick was equipped with a 3.8-liter, electronically controlled, fuel-injected, 6-

cylinder gasoline engine and an automatic overdrive transmission. Postaccident inspection

showed that accelerator cable movement was smooth, without restriction, binding, or

sticking, as was throttle movement. Throttle return was consistent and spring force was

firm. The throttle position sensor was securely mounted to the throttle body and all

associated wiring was secure and in good condition. The vehicle’s electronic control

module (ECM), which controls fuel and ignition timing, revealed no fault or error codes.

A query of the National Highway Traffic Safety Administration’s (NHTSA’s) Office of

Defect Investigation database found no recalls or open investigations involving the

vehicle’s throttle controls and no incidents of unintended accelerations. No defect,

deficiency, or abnormality was found in the vehicle’s throttle controls.

All tires were examined and found to comply with California’s vehicle inspection

criteria for tread depth requirements.7 The Buick was equipped with P215/60R16

(standard load range) tires, as recommended by the vehicle manufacturer. Results of the

tire and wheel assembly inspections were unremarkable, except for an area of scuffing and

minor tearing of the left front outer sidewall that extended into the area of the shoulder.

6 The weight of a vehicle without passengers or payload, but including all fluids and other equipment

specified as standard.

7 Vehicle Code, Section 27465.
Factual 9 Highway Accident Report

The Buick was equipped with a power-assisted, dual-circuit hydraulic brake system

configured with front disc brakes and rear drum brakes. The master cylinder was adequately

filled with fluid and the power booster supply check valve functioned properly. All wheel

hubs rotated freely and without indications of drag or out-of-round conditions. Examination

of each brake assembly and associated hydraulic lines revealed no leaks, restrictions, or

operational defects. The brake pedal was intact and functional, offering consistent

resistance and approximately 2 1/2 inches of nonpower-assisted travel. The rubber cover on

the brake pedal was worn on the lower right edge, revealing the metal beneath (see figure

3). Separation between the brake pedal and the accelerator at the closest point was 2 inches.

California Highway Patrol (CHP) officers tested the vehicle’s brake operation

before the Buick was removed from the scene. They reported that an initial (boosterassisted) brake application was held for 30 seconds without pedal drop or fade and that all

wheel assemblies locked when force was applied to the brake pedal. 

Inspection results of the service and parking brake systems were unremarkable,

except for slight fluid seepage noted at the right rear wheel cylinder dust covers. The brake

components showed no signs of active fluid loss or contamination.

The Buick was equipped with a hydraulic rack-and-pinion power steering system.

The power steering fluid reservoir was filled to the add level with clean, semitranslucent fluid.

The pump drive belt was intact and free from obvious glazing, defects, or cracking. The lowpressure return line exhibited active fluid leaking and had been double-clamped at two

locations. Results of the examination of the steering linkages and the front suspension were

unremarkable. Inspection of the rear suspension revealed dry rotting or cracking of the rubber

strut boots on the rear suspension and evidence of oil leakage from each strut assembly. A

small area of wear, consistent with tire contact, was also noted within the rear left wheel well.

Figure 3. Accident vehicle’s brake pedal.
Factual 10 Highway Accident Report

Review of available maintenance records showed that the vehicle had received

general routine maintenance. The records indicated no driver complaints or major repairs

to the vehicle’s throttle controls, braking, or steering systems. California does not have an

annual vehicle safety inspection program, and no inspection certificate was available for

review.

Accident-Related Damage

The Buick sustained frontal damage encompassing the front bumper, forward light

fixtures, radiator grill, radiator and support, left front quarter panel, windshield, roof, both

side mirrors, and rear antenna. (See figure 4.) The two side-view mirrors were missing,

and the shattered windshield had two distinct impact or indentation locations; remnants

and debris from items struck were found embedded in the windshield. The right side of the

front bumper had light blue paint transfer, and the rubber portion of the right rear bumper

had white paint transfer. The left bumper quarter panel was missing and exhibited

exposed, jagged edges. The bumper was angled upward from the frame, consistent with

accident damage. The Buick’s airbag had deployed.

Damage to the Mercedes consisted of horizontal surface scratching to the rear

bumper cover.

Figure 4. Postaccident damage to 1992 Buick LeSabre.
Factual 11 Highway Accident Report

Highway Information

Highway Design

The accident occurred on westbound Arizona Avenue between Fourth Street and

Ocean Avenue. Arizona Avenue is a collector roadway that carries traffic between

residential neighborhoods and the arterial street network. Collectors generally have a

mixture of residential and commercial land uses along them. According to Santa Monica’s

“Transportation Circulation Element,” average daily traffic volumes on collector

roadways are to be held to below 15,000 vehicles in order to maintain acceptable levels of

service at intersections and an environment compatible with residential land uses. 

Arizona Avenue is a straight, level, asphalt, undivided roadway; it has one travel

lane each westbound and eastbound. The roadway is 48 feet wide. The two travel lanes are

separated by solid, double-yellow pavement markings. The posted speed limit is 25 mph.

Marked parallel parking spaces border the sides of the through lanes, and concrete

sidewalks are adjacent to the outer edges of the street.

At the time of the accident, Arizona Avenue was closed to vehicular traffic

between the alley east of Ocean Avenue and the alley west of Fourth Street (see figure 5),

and the roadway was being used as an outdoor farmers’ market from 9:00 a.m. to 2:00 p.m.

Prior to the beginning of the market area, westbound traffic was allowed to use Arizona

Avenue between Fourth Street and an alley, located between Third and Fourth Streets, to

access a bank parking lot on the southwest corner. A full closure was located at the west

side of the intersection of Arizona Avenue and the alley between Third and Fourth Streets.

Past the closure points on Arizona Avenue, fruit and vegetable vendor canopy tents

occupied the outer edges of the roadway from the alley midway between Third and Fourth

Streets to the alley midway between Second Street and Ocean Avenue. 
Factual 12 Highway Accident Report

Figure 5. Road closures in place for SMCFM.
Factual 13 Highway Accident Report

Traffic Volume and Accident History

Santa Monica reported that weekday peak-hour traffic counts were last obtained in

October 2002 and indicated the following traffic volumes:

Table 2. Traffic counts.

The city provided the following statistics, which it obtained from California’s

Statewide Integrated Traffic Record System, regarding the number of accidents recorded

on Arizona Avenue between Ocean Avenue and Fifth Street for the period from January 1,

1999, to June 30, 2002: 

Table 3. Accident history.

No fatal accidents were reported at any of these locations during that period.

According to the city, the SMCFM has had no reported accidents during its hours of

operation (9:00 a.m. to 2:00 p.m.) since it opened in 1981. 

Traffic Control 

Santa Monica provided a temporary traffic plan for the SMCFM to Safety Board

investigators. The undated and unsigned temporary traffic plan consisted of a single sheet

of paper (8 1/2 x 11 inches) on which a roadway diagram was hand-drawn (see figure 6);

the diagram indicated where barricades should be placed in the roadway. The plan did not

cite any specific Manual on Uniform Traffic Control Devices (MUTCD) or Caltrans

[California Department of Transportation] Traffic Manual (CTM) barricade types or

traffic channelization devices8

 to be used. According to the director of the SMCFM, the

traffic plan had been developed in 1981 when the market opened and revised in 1986

when the market expanded onto Second Street. It had not been revised, reevaluated, or

updated since then.

Intersecting roadways Traffic count

Ocean Avenue and Arizona Avenue 9,867

Second Street and Arizona Avenue 6,675

Third Street and Arizona Avenue 7,706

Fourth Street and Arizona Avenue 9,987

Intersection Number of accidents 

reported

Number of pedestrian 

accidents

Ocean Avenue and Arizona Avenue 21 2

Second Street and Arizona Avenue 11 0

Third Street and Arizona Avenue 4 0

Fourth Street and Arizona Avenue 14 1

Fifth Street and Arizona Avenue 14 1

8 Traffic channelization devices include barricades, cones, and drums that are placed in the roadway.
Factual 14 Highway Accident Report

Figure 6. Temporary traffic plan (1986 version).
Factual 15 Highway Accident Report

According to the SMCFM director, Arizona Avenue was blocked at the entrances to

the market by two MUTCD type I barricades,9

 supplemented by two A-frame plastic

barricades (see figure 7). The barricades were placed in the roadway about 7:00 a.m. every

Wednesday, remained in place during the event, and removed about 3:00 p.m. Orange,

diamond-shaped ROAD CLOSED AHEAD warning signs (designated “W-20” signs in the

MUTCD and “C-19” in the CTM), attached to temporary fixtures, were placed on the

centerlines of Arizona Avenue and Second Street (see figure 8),10 about 1/2 block before the

road closure. No other advance warning signs were used. When Safety Board investigators

observed the SMCFM in operation on July 23, 2003, barricades were in place at those

locations indicated in the temporary traffic plan. Contract personnel, hired by the city’s

Office of Economic Development, placed and removed the barricades and warning signs.

9 The CTM, Chapter 5, Section 5-05.6, “Channelizing Devices, F. Barricade Application,”

recommends the use of type III barricades for full road closures, as shown in Typical Application 5-8 on

page 5-99, “Road Closed with Off-Site Detour.”

10 In this photograph, taken a week after the accident, a small pickup truck is parked in the middle of the

street. No vehicles were parked in the middle of the street on the day of the accident.

Figure 7. Market barricades.
Factual 16 Highway Accident Report

Traffic Signals

Three-phase, electrically operated traffic signals were in place at all street

intersections on Arizona Avenue between Ocean Avenue and Fifth Street. Traffic signals

were not in place at the alley intersections. The signal at Arizona Avenue and Third Street

was a “pedestrian only” signal; Third Street is a promenade (or pedestrian mall), and

vehicles do not approach Arizona Avenue from it. Even when the SMCFM was operating

and vehicles were prohibited on Arizona Avenue from the alley between Second Street

and Ocean Avenue and the alley between Fourth and Third Streets, all traffic signals

continued to operate in their normal mode. The traffic signals at Second Street and the

Third Street promenade continued to operate, even though vehicular traffic did not cross

either intersection while the farmers’ market was in operation. Both signals were visible to

traffic on north- and southbound Arizona Avenue, and the signal at the Second Street

intersection was visible to east- and westbound Second Street traffic. (See figure 9.)

Traffic Control at Service Alley

As investigators walked from Fourth Street to Ocean Avenue, they noted a service

alley, intersecting Arizona Avenue midway between Second and Third Streets, that was

open to traffic. When they first passed this alley, no barricades were in place. Upon

returning from Ocean Avenue less than 15 minutes later, the investigators observed that

market personnel had placed three-wheeled vehicles at the service alley in an apparent

attempt to block vehicular traffic.

Figure 8. Advance warning sign on Arizona Avenue, just west of Fourth Street (postaccident).
Factual 17 Highway Accident Report

Third Street Promenade

The Third Street promenade intersects Arizona Avenue midway in the SMCFM. It

is a dedicated pedestrian mall that is permanently closed to vehicular traffic. Metal

bollards11 are positioned at the entrances to the mall at Arizona Avenue, Colorado Avenue,

and Wilshire Boulevard. According to the city, “the bollards are intended to keep vehicles

off the Third Street promenade on a full-time, permanent basis.” Four bollards are

embedded into the Third Street roadway at each intersection, and they extend

approximately 24 inches above the ground. (See figure 10.) They are locked into place

with a padlock and can be lowered into the ground to allow access by emergency vehicles.

Emergency response personnel have keys to the padlocks.

According to city officials, the metal bollards were installed at the mall entrances

because the promenade was designated a permanent pedestrian mall. Officials indicated

that bollards were not considered for the SMCFM entrances because the market does not

operate on a full-time basis, necessitating permanent closure of Arizona Avenue. 

Figure 9. Traffic signal at Second Street and Arizona Avenue.

11 A bollard is a thick, low vertical post used to exclude or divert motor vehicles from a road, lawn, or

other restricted area.
Factual 18 Highway Accident Report

Emergency Response

About 1:47 p.m. on July 16, 2003, the SMPD Communications Center in Santa

Monica received several wireless 9-1-1 calls reporting an accident at Second Street and

Arizona Avenue. SMPD officers arrived within 1 minute to the scene. In all, some 400

municipal employees and law enforcement, emergency medical service, and fire

department personnel from the SMPD, CHP, Beverly Hills Police Department, Los

Angeles Police Department, Culver City Police Department, Los Angeles County

Sheriff’s Department, Santa Monica Fire Department (SMFD), Los Angeles County Fire

Department (LACFD), Los Angeles City Fire Department (LAFD), and the Culver City

Fire Department (CCFD) responded to the accident. Responders provided triage, patient

care, patient transport, traffic control, and investigation. 

The SMFD dispatched 21 vehicles and 41 personnel to the scene, and once mutual

aid was requested, other agencies provided additional support. The LAFD, LACFD, and

CCFD sent 24 vehicles, 3 helicopters, and 66 personnel. In all, 107 fire department

personnel responded to the scene. The SMFD, which is responsible for an 8.2-square mile

area, has six certified advanced life support units; four are fire engines and two are

ambulances. All SMFD firefighters are certified emergency medical technicians or

paramedics. In the event of a large-scale response, the SMFD has an agreement with a

private ambulance company to provide transportation for medical emergencies, and

multiple units responded to this accident scene.

Figure 10. Bollards in place at the Third Street pedestrian promenade.
Factual 19 Highway Accident Report

The closest SMFD fire station was about 5 blocks from the scene. By 1:50 p.m.,

the first fire and emergency medical services had arrived on scene via the Arizona

Avenue-Fourth Street entrance to the SMCFM. All units were on scene within 10 minutes

of the accident dispatch.

The first fire officer on scene became the incident commander (IC) and

immediately declared the scene a multi-casualty incident (MCI), initiated the MCI plan,

and called for six more ambulances and two more engine companies. A medical command

position was initiated and the SMFD firefighter who assumed the role of medical

commander began contacting the nearest hospitals to advise them of the situation and to

expect numerous patients. A firefighter-paramedic was designated treatment unit leader

and began to set up a treatment area at the scene. The IC did a walk-through of the entire

scene and, after further assessment, called for all remaining SMFD units, 15 additional

ambulances, and 4 engine companies. The IC also requested the use of medical “cache”

trailers. The SMFD maintains one of these trailers at each station in Santa Monica for

deployment during disasters, and they were a source of medical supplies and backboards12

during the response. According to the SMFD fire chief, these trailers were “vital” to the

response effort, since the number of injured was larger than the supply of backboards and

other equipment available from the responding units.

After the injured were triaged at their locations, they were moved to ambulances

for transport to a hospital or to the treatment location on scene. When all eight local

hospitals began to fill up, helicopters were requested for transport of the injured to other

hospitals. Among the patients treated at the scene, 22 were considered “walking

wounded” and were transported by city bus to a hospital. The more seriously injured, as

determined by on-scene triage, were transported to hospitals by ambulance and helicopter. 

During the emergency response, the IC requested mutual aid from other local fire

departments to assist the SMFD, since all available SMFD units had responded to the

scene. The LAFD, LACFD, and CCFD responded to the 2:09 p.m. request and were either

on scene 11 minutes later or filled in at the SMFD stations and handled calls there while

the SMFD units were on scene. 

The emergency responders to this accident carried out their activities in

accordance with the “California Fire Service and Rescue Emergency Mutual Aid Plan,”

which supports the concepts of the incident command system, the integrated emergency

management system, and multihazard response planning. The purpose of the State mutual

aid plan is to provide for systematic mobilization, organization, and operation of the

State’s fire and rescue resources in mitigating the effects of disasters, whether natural or

man-made.

12 A backboard is a rigid board splint on which patients are secured by straps. It is commonly used in

instances of known or suspected spinal injury to prevent further injury during transport.
Factual 20 Highway Accident Report

Under the coordination of the SMFD, Santa Monica has participated in regularly

held drills, covering scenarios such as earthquakes, fires, and other natural disasters. The

purpose of these drills is to test the readiness and response of fire, police, public works,

transportation, and other city departments.

Operational Information

History of Farmers’ Markets

The number of farmers’ markets in the United States exceeds 3,100,13 a figure that

increased by 79 percent from 1994 to 2002. The U.S. Department of Agriculture (USDA)

supports and promotes farmers’ markets. In August 1998, the USDA, through its

Agricultural Marketing Service, developed a “Direct Marketing Action Plan”14 to identify

direct marketing issues and opportunities affecting farmers, promote development and

operation of farmers’ markets, and conduct, support, and promote research. The USDA

has no Federal regulatory or enforcement authority over farmers’ markets. It maintains a

database of market locations throughout the Nation; inclusion is voluntary, and the

database does not track safety issues affecting farmers’ markets. The decision to place a

market in a certain location, the permitting requirements, and any traffic control plans

necessary to ensure the safety of a market are left to the discretion of local jurisdictions.

The State’s Department of Agriculture certifies farmers’ markets in California.

Only certified farmers, nonprofit organizations, or governmental entities can operate a

certified farmers’ market (CFM) in the State. Both a market’s operator and the individual

vendors must receive certification from their county’s agricultural commissioner. The

State promotes the markets in order to provide California farmers with an outlet for and

the public with access to fresh farm products at lower cost. According to the California

Department of Agriculture, to receive State certification, a market operator must complete

an application form and pay a fee. The State requires a map of the proposed location but

does not approve or control the physical location of the market; it does not require that a

traffic control plan be submitted. The purpose of the map is to allow State inspectors to

visit sites to determine where certified and noncertified products are being sold.

The State’s Department of Agriculture reports more than 300 CFMs in California,

of which 80 are located within the Los Angeles County limits. The number of county

markets that operate on dedicated roadways requiring temporary road closures is 27.

Santa Monica sponsors four CFMs: the Wednesday Market, the Sunday Market,

the Saturday Downtown Market, and the Saturday Pico Street Market. The city, which

organizes and manages these markets, estimates that 900,000 shoppers visit them every

year. The accident occurred at the Wednesday Market.

13 See <http://www.ams.usda.gov/farmersmarkets/facts.htm>.

14 See <http://www.ams.udsa.gov/directmarketing/frmplan.htm>.
Factual 21 Highway Accident Report

The Wednesday Market operates on Arizona Avenue between Fourth Street and

Ocean Avenue every Wednesday from 9:00 a.m. to 2:00 p.m. It opened in July 1981 and

was the first CFM established in Santa Monica. The Saturday Downtown Market,

established in May 1991, operates in the same location where the accident occurred. The

Saturday Pico Street Market and the Sunday Market operate in off-street facilities.

The Wednesday Market received its most recent annual certification prior to the

accident on February 25, 2003. The market includes approximately 90 vendors who set up

portable canopy tents along Arizona Avenue’s parking lanes. The city estimates the

Wednesday Market draws about 9,000 visitors per week.

City of Santa Monica

Santa Monica’s city manager reports directly to the city’s mayor and seven-person

council. The city manager oversees Santa Monica’s 10 departments, including the Office

of Resource Management, which, through its economic development unit, was directly

responsible for the operation of the SMCFM.

The city’s Transportation Management Division is part of the Office of Planning

and Community Development, another of the 10 departments that report to the city

manager. That division’s traffic operation unit studies parking and traffic conditions

throughout the city and develops plans and recommendations to improve the movement

and safety of pedestrians, bicycles, buses, trucks, and cars. The city accomplishes many of

these functions through private consultants and contractors. 

The Open Space Management Division is responsible for issuing the city permits

required by individuals and organizations seeking to hold community events on public

property. When such events require the closure of a city street, the Transportation

Management Division must approve any temporary traffic control plans deemed necessary

to hold the event safely. It also assesses the level of traffic disruption and determines the

level of temporary traffic control necessary to safely conduct the event under

consideration. According to Santa Monica officials, the Transportation Management

Division uses the Work Area Traffic Control Handbook (WATCH)15 to determine the level

of temporary traffic control needed.

The traffic operations unit is responsible for installing, maintaining, and repairing

all traffic control devices, including traffic signals, traffic signs, roadway striping, painted

curb zones, and parking meters. The city has approximately 160 traffic signals, 25,000

traffic signs, and 6,000 parking meters. In emergency situations, this unit also provides

personnel and materials to assist with emergency traffic control. Services provided include

installing road barricades and traffic signs and repairing traffic signals.

15 Uniform Practices and Utility Coordination Committee, Southern California Chapter, American

Public Works Association, Eighth Edition (Anaheim, CA: BNI Publications, 1996).
Factual 22 Highway Accident Report

Community Event Permitting Requirements

Santa Monica Municipal Code, Sections 4.68.040 through 4.68.220, governs the

requirements for and application and issuance of community event permits.16 Section

4.68.040 requires a permit for (1) any gathering of 150 or more people on city-owned,

-controlled or -maintained property; or (2) any activity or event on public property that

requires the placement of a tent, canopy, or other temporary structure. The city owns and

operates the SMCFM, and, according to city officials, the community event permitting

statute does not apply to the SMCFM.

The permitting process addresses requirements for certain events when street

closure is explicitly requested; it does not require submission of a traffic control plan for

those events. Applicants seeking street closure must submit for review by the fire and

police departments a scaled site map that includes the placement of all event equipment.

The purpose of this review is to ensure that emergency vehicles will have access to the

affected area throughout the event; it is not a review for pedestrian or traffic safety.

Other Information

Manual on Uniform Traffic Control Devices 

The MUTCD, which is produced under the authority of the U.S. Department of

Transportation, Federal Highway Administration, contains the basic principles governing

the design and use of traffic control devices for all streets and highways open to public

travel, regardless of type or class or the public agency having jurisdiction. At the time of

the accident, the MUTCD 2000, or Millennium Edition, was current.17

Chapter 6 of the MUTCD, entitled “Temporary Traffic Control,” applies to the

deployment and use of devices for traffic control when the normal traffic flow is

disrupted. It defines the primary function of temporary traffic control as providing for the

safe and efficient movement of vehicles, bicyclists, and pedestrians through or around all

temporary traffic control zones while reasonably protecting persons and equipment. The

MUTCD provides the following standards:

Temporary traffic control plans and devices shall be the responsibility of the

authority of a public body or official having jurisdiction for guiding road users.

There shall be adequate statutory authority for the implementation and

enforcement of needed road user regulations, parking controls, speed zoning, and

incident management. Such statutes shall provide sufficient flexibility in the

application of temporary traffic control to meet the needs of changing conditions

in the temporary traffic control zone.18

16 Administrative Instruction No. II-4-4, July 15, 2003.

17 In November 2003, the Federal Highway Administration issued the MUTCD 2003, which California

adopted, with a State supplement, on May 20, 2004. The chapter on temporary traffic control in the MUTCD

2003 is substantially the same as the corresponding chapter in the MUTCD 2000.

18 MUTCD 2000, Millennium Edition, December 2001, Section 6A.01.
Factual 23 Highway Accident Report

Chapter 6B.01 of the MUTCD, “Fundamental Principles of Temporary Traffic

Control,” notes: “The control of road users through a temporary traffic control zone shall

be an essential part of highway construction, utility work, maintenance operations, and

incident management.” The MUTCD makes no distinction pertaining to the reason for a

road closure or other measure. Section 6C.01 states:

Temporary traffic control plans play a vital role in providing continuity of safe

and efficient road user flow when a work zone, incident, or other event [emphasis

added] temporarily disrupts normal road user flow.

The MUTCD lists several typical applications (TAs) to aid in selecting the most

appropriate temporary traffic control devices. The applications can be altered to suit the

specific conditions of a particular site; supplemental devices may be added and devices

included in a TA can be deleted. 

The model application for road closures with off-site detour is model TA-8 (see

figure 11). It states that a ROAD CLOSED19 sign mounted on type III barricades (see figure

12) may be located at the edge of a roadway that is not being closed to all traffic.20 If the

road is closed a short distance beyond the intersection and a few origin or destination points

are also beyond the intersection (for example, a few residences), the ROAD CLOSED sign

may be placed on a type III barricade21 placed in the center of the roadway.

Section 6F.75 of the MUTCD, which describes the use of temporary traffic

barriers, states:

Temporary traffic barriers are devices designed to help prevent penetration by

vehicles while minimizing injuries to vehicle occupants, and designed to protect

workers, bicyclists, and pedestrians .... They are also used for certain special

events or in other temporary traffic control contexts where separation and

channelization of vehicle and pedestrian movements are needed. 

The MUTCD defines crash cushions in section 6F.76, which refers the reader to

the American Association of State Highway and Transportation Officials (AASHTO)

Roadside Design Guide for more information on the use of crash cushions. Section 6F.76

of the MUTCD states: 

Crash cushions are systems that mitigate the effects of errant vehicles that strike

obstacles, either by smoothly decelerating the vehicle to a stop when hit head-on,

or by redirecting the errant vehicle. The two types of crash cushions that are used

in temporary traffic control zones are stationary crash cushions and truck mounted

attenuators. Crash cushions in temporary traffic control zones help protect the

drivers from the exposed ends of barriers, fixed objects, shadow vehicles, and

other obstacles.

19 MUTCD 2000, Millennium Edition, December 2001, Section 2B-42, “ROAD CLOSED Sign (R11-2).”

20 The MUTCD designates traffic barricades as types I, II, and III. Type I and II barricades are to be

used when traffic is maintained through a work area; type I barricades are for use on urban or low-speed

roads or streets, and type II barricades are for use on expressways, freeways, and other high-speed roadways.

Type III barricades are to be used to close or partially close a road. 

21 MUTCD 2000, Millennium Edition, Section 6F-4, “Channeling Devices.”
Factual 24 Highway Accident Report

Figure 11. TA-8, the model application for road closures with off-site detour.
Factual 25 Highway Accident Report

Section 6G.04 of the MUTCD, “Modifications to Fulfill Special Needs,” provides

guidance on adding supplemental devices to temporary traffic control applications.

According to section 6G.04, “When conditions are more complex, typical applications

should be modified by incorporating appropriate devices and practices from the following

list,” which includes temporary traffic barriers (#8) and crash cushions (#9).

Roadside Design Guide

The AASHTO Roadside Design Guide synthesizes current information and

operating practices related to roadside safety. Chapter 9, “Traffic Barriers, Traffic Control

Devices, and Other Safety Features for Work Zones,” describes the safety, functional, and

structural aspects of traffic barriers, traffic control devices, and safety features used in

work zones and provides guidance for their application. The guide indicates that chapter 9

is not a stand-alone document and that the information in it must be used in conjunction

with traffic control guidance in the MUTCD.

Section 9.2 of the Roadside Design Guide, “Traffic Barriers,” states that work zone

traffic barriers are designed either as permanent barriers or as temporary barriers that can

be easily relocated. It notes that one function of these barriers is “to separate pedestrians

Figure 12. Type III barricade.
Factual 26 Highway Accident Report

from vehicular traffic.” Subsection 9.2.1 describes various temporary longitudinal barriers

used to segregate vehicle traffic from pedestrians, workers, or equipment; these barriers

are of sufficient structural strength to redirect or resist errant vehicles. Section 9.3, “Crash

Cushions,” describes stationary crash cushions available for temporary use. 

Caltrans Traffic Manual 

In 1996, the California Department of Transportation published its CTM, which

set State standards for traffic control devices at the time of the accident. Prior to

publication of the MUTCD 2003, California had chosen not to adopt the national

MUTCD, as the Federal Highway Administration allows;22 therefore, the MUTCD was

not controlling at the time of the farmers’ market incident. The CTM was very similar to

the 1988 MUTCD with revision 3 (3/1993). Section 5-01.1 of the CTM defined a

workspace as a location where the normal function of the roadway is suspended. The

CTM also listed TAs, and application 5-8 was identical to the MUTCD 2000 TA-8.

WATCH Manual

According to Santa Monica’s Transportation Management Division, the WATCH

manual provides guidance for the setup and operation of all work areas occupying city streets.

The manual sets forth basic principles and recommends standards to be observed by all those

who perform work in a public street. It defines the term work to include activities such as

store openings, news and theater events, and commercial filming. As do the MUTCD and the

CTM, the WATCH manual includes several examples of lane and road closures to be used as

guides, one of which is an application for “closing of local streets.” The application calls for

the roadway to be closed using two ROAD CLOSED (C5) signs mounted on type III

barricades and advance warning signs on the three approaches to the intersection.

Bourbon Street Promenade, New Orleans, Louisiana 

Bourbon Street was dedicated as a public thoroughfare in 1751, and in 1971, the

New Orleans City Council enacted an ordinance designating the 100 to 800 blocks of

Bourbon Street as a pedestrian mall during nighttime hours as a means to promote

tourism. To protect pedestrians on this segment of the street, the city uses removable

bollards, which are hollow cast-iron poles, painted yellow, and placed into metal collars

embedded in the roadway. The bollards extend approximately 40 inches above the ground

and 6 inches into the ground. According to the traffic engineer for the New Orleans

Department of Public Works, the city does not maintain records of whether the bollards

are effective in stopping errant vehicles from entering the pedestrian mall; the bollards are

often observed to be bent and to require replacement.

22 MUTCD 2000, Millennium Edition, Section 1A.07, “Responsibility for Traffic Control Devices,”

states: “When a State or other Federal agency manual or supplement is required, they shall be in substantial

conformance with the national Manual on Uniform Traffic Control Devices.” Title 23 CFR 655.603 requires

that traffic control devices on all streets and highways open to public travel in each State be in substantial

conformance with standards issued or endorsed by the Federal Highway Administrator.
Factual 27 Highway Accident Report

Unintended Acceleration

NHTSA, in An Examination of Sudden Acceleration, has defined unintended

acceleration (also known as sudden acceleration) as “an unintended, unexpected, high-power

acceleration from a stationary position or a very low initial speed accompanied by an

apparent loss of braking effectiveness.”23 The definition includes the phrase “an apparent

loss of braking effectiveness,” according to NHTSA, because drivers often claim they were

pressing on the brake pedal but the vehicle would not stop. The study concluded:

For a sudden acceleration incident in which there is no evidence of throttle

sticking or cruise control malfunction, the inescapable conclusion is that these

definitely involve the driver inadvertently pressing the accelerator instead of, or in

addition to, the brake pedal.

Both Transport Canada24 and the Japanese Ministry of Transport25 have also examined this

issue; the former concluded that driver error is the cause of the unintended acceleration

phenomenon, and the latter found no common mechanical cause for sudden or unintended

acceleration.

Highway Vehicle Event Data Recorders

 The accident vehicle was not equipped with an event data recorder (EDR), nor

was it required to be. It did have an electronic air bag control module and an engine ECM;

neither device was designed for, or capable of, recording accident data. Currently, a small

number of late-model automobiles and light-duty trucks are equipped with air bag control

modules that can capture and record a limited amount of accident data. Additionally, many

heavy-duty trucks are equipped with ECMs or with transmission control modules that

record critical vehicle performance data. On a limited basis, General Motors, Ford, and,

more recently, Daimler-Chrysler, have begun integrating crash data collection

technologies in their vehicles. In the absence of industry standards or government

regulations, each manufacturer has determined which parameters to record and methods to

use in accessing the data from these devices. Manufacturers currently record different data

parameters and use different formats, tools, and procedures to access the recorded data. 

NHTSA and the automobile industry have been examining the utility of highway

vehicle EDRs since the mid-1970s. In 1974, as part of its Disc Recorder Project, NHTSA

equipped 1,000 vehicles with EDRs in several fleets that logged a total of 26 million

miles. Researchers subsequently analyzed 26 crashes in which EDR-equipped vehicles

were involved, measured Delta Vs up to 20 mph, and collected deceleration-time histories.

During the same year, General Motors introduced the first regular production driverpassenger airbag systems in selected vehicles. These systems incorporated a datarecording feature designed to activate when the air bags deployed during severe crashes. 

23 U.S. Department of Transportation, Transportation Systems Center, An Examination of Sudden

Acceleration, Report HS-807-367 (Cambridge, MA, January 1989). 

24 Transport Canada, Investigation of Sudden Acceleration Incidents (1989).

25 Japanese Ministry of Transport, An Investigation on Sudden Starting and/or Acceleration of Vehicles

With Automatic Transmissions (1989).
Factual 28 Highway Accident Report

As a result of its 1997 public forum26 on air bag, seat belt, and child restraint use,

the Safety Board issued an EDR recommendation to NHTSA and a companion

recommendation to the automobile manufacturers. The Board urged NHTSA to:

H-97-18

Develop and implement, in conjunction with the domestic and international

automobile manufacturers, a plan to gather better information on crash

pulses and other crash parameters in actual crashes, utilizing current or

augmented crash sensing and recording devices.

In response, NHTSA formed an EDR working group in 1998 that included representatives

from the Safety Board and automobile manufacturers. The group’s objective, as stated by

NHTSA, was to facilitate the collection and utilization of collision avoidance and

crashworthiness data from on-board EDRs. The working group issued a final report in

2001 addressing issues such as the status of EDR technology, data elements, data retrieval,

data collection and storage, permanent records, privacy and legal implications, customers

for and uses of EDR data, and demonstration of EDR technology. As a result of these

efforts, the Safety Board classified the recommendation to NHTSA “Closed—Exceeds

Recommended Action” on July 18, 2002, and classified the recommendation to the

automobile manufacturers “Closed—Acceptable Action” on April 22, 2004.

In 1998, as the result of an accident investigation in Slinger, Wisconsin, involving

four vehicles,27 the Safety Board issued EDR recommendations to the American Trucking

Associations, the International Brotherhood of Teamsters, the Motor Freight Carrier

Association, the Independent Truckers and Drivers, the National Private Truck Council,

and the Owner-Operator Independent Drivers Association, Inc. The circumstances of the

accident made it difficult to reconstruct the events, and the Safety Board concluded that,

had the accident vehicle been equipped with an EDR, investigators would have been able

to determine the speed at which the striking vehicle was traveling prior to losing control.

The Safety Board therefore asked the trucking industry to:

H-98-23 and -26

Advise your members to equip their commercial vehicle fleets with

automated and tamper-proof on-board recording devices, such as

tachographs or computerized recorders, to identify information concerning

both driver and vehicle operating characteristics.

26 National Transportation Safety Board, Proceedings of the National Transportation Safety Board

Public Forum on Air Bags and Child Passenger Safety, Report of Proceedings NTSB/RP-97/01

(Washington, DC: NTSB, 1997).

27 National Transportation Safety Board, Multiple Vehicle Crossover Accident, Slinger, Wisconsin

February 12, 1997, Highway Accident Report NTSB/HAR-98/01 (Washington, DC: NTSB, 1998).
Factual 29 Highway Accident Report

The industry generally declined to do so, and the Safety Board classified the

recommendations “Closed—Unacceptable Response” for all of the associations.

In 1999, the Safety Board again addressed the need for highway vehicle EDRs in

its special investigation report on school bus and motorcoach safety.28 The report noted

that in several studies, drivers of EDR-equipped vehicles have demonstrated a decrease in

accidents, and the Safety Board concluded that EDRs could help reduce the accident rates

of fleet vehicles. The Board recommended that NHTSA:

H-99-53

Require that all school buses and motorcoaches manufactured after January

1, 2003, be equipped with on-board recording systems that record vehicle

parameters, including, at a minimum, lateral acceleration, longitudinal

acceleration, vertical acceleration, heading, vehicle speed, engine speed,

driver’s seat belt status, braking input, steering input, gear selection, turn

signal status (left/right), brake light status (on/off), head/tail light status

(on/off), passenger door status (open/closed), emergency door status

(open/closed), hazard light status (on/off), brake system status

(normal/warning), and flashing red light status (on/off) (School buses

only). For those buses so equipped, the following should also be recorded:

status of additional seat belts, airbag deployment criteria, airbag

deployment time, and airbag deployment energy. The on-board recording

system should record data at a sampling rate that is sufficient to define

vehicle dynamics and should be capable of preserving data in the event of a

vehicle crash or an electrical power loss. In addition, the on-board

recording system should be mounted to the bus body, not the chassis, to

ensure that the data necessary for defining bus body motion are recorded.

The Safety Board also recommended that NHTSA:

H-99-54

Develop and implement, in cooperation with other government agencies

and industry, standards for on-board recording of bus crash data that

address, at a minimum, parameters to be recorded, data sampling rates,

duration of recording, interface configurations, data storage format,

incorporation of fleet management tools, fluid immersion survivability,

impact shock survivability, crush and penetration survivability, fire

survivability, independent power supply, and ability to accommodate future

requirements and technological advances.

28 National Transportation Safety Board, Bus Crashworthiness Issues, Highway Special Investigation

Report NTSB/SIR-99/04 (Washington, DC: NTSB, 1999).
Factual 30 Highway Accident Report

NHTSA responded that its EDR working group would consider the recommended

data elements, and in 2000, NHTSA established a second working group to concentrate on

EDRs for trucks, motorcoaches, and school buses. 

In August 2001, the EDR working group issued a final report. Its findings include:

1. EDRs have the potential to greatly improve highway safety, for example, by

improving occupant protection systems and improving the accuracy of crash

reconstructions. 

2. EDR technology has potential safety applications for all classes of motor

vehicles.

3. A wide range of crash-related and other data elements have been identified

which might usefully be captured by future EDR systems.

4. NHTSA has incorporated EDR data collection in its motor vehicle research

databases. 

5. Open access to EDR data (minus personal identifiers) will benefit researchers,

crash investigators, and manufacturers in improving safety on the highways. 

6. Studies of EDRs in Europe and the U.S. have shown that driver and employee

awareness of an on-board EDR reduces the number and severity of driver’s

crashes. 

7. Given the differing nature of cars, vans, SUVs, and other lightweight vehicles,

compared to heavy trucks, school buses, and motorcoaches, different EDR

systems may be required to meet the needs of each vehicle class. 

8. The degree of benefit from EDRs is directly related to the number of vehicles

operating with an EDR and the current infrastructure’s ability to use and

assimilate these data. 

9. Automatic crash notification systems integrate the on-board crash sensing and

EDR technology with other electronic systems, such as global positioning

systems and cellular telephones, to provide early notification of the

occurrence, nature, and location of a serious collision. 

10. Most systems utilize proprietary technology and require the manufacturer to

download and analyze the data.

The Safety Board classified Safety Recommendations H-99-53 and -54 “Open—

Acceptable Response” on April 15, 2004.

In 2002, the Society of Automotive Engineers (SAE) and the Institute of Electrical

and Electronics Engineers (IEEE) agreed to work together to voluntarily develop

standardization of data output and retrieval protocols that would facilitate analysis and

promote compatibility of EDR data. In October 2002, NHTSA published a request for

comments on EDRs that addressed major issue areas, such as the standardization of data

and privacy issues. The Safety Board responded, encouraging NHTSA to maintain its
Factual 31 Highway Accident Report

progress toward requiring that (1) all school buses and motorcoaches be equipped with

EDRs and (2) standards for on-board recording of bus crash data be developed. NHTSA

also began participating in an International Harmonized Research Activities EDR working

group in 2002.

In December 2002, the Safety Board issued additional recommendations regarding

EDRs as the result of its investigation of an accident near Canon City, Colorado, in which

a motorcoach lost control on an icy roadway, left the roadway, and overturned before

coming to rest.29 The Safety Board asked the IEEE and the SAE to:

H-02-35

Work together, as part of your initiative to establish on-board vehicle

recorder standards, to develop standards for brake and transmission

electronic control units that require those units to store a full history of

electronic fault codes that are time stamped using a recognized clock

synchronized with other on-board event data recording devices.

As a result, the IEEE is developing an amendment to its EDR standards that would

require brake and transmission electronic control units to store a full history of electronic

fault codes that are time-stamped by a recognized clock synchronized with other on-board

EDRs. The Safety Board classified Safety Recommendation H-02-35 to the IEEE

“Open—Acceptable Response” on March 2, 2004. The SAE indicated that it is not

developing an EDR standard or recommended practice for heavy vehicles. The Safety

Board continues to urge the SAE to work with the IEEE on EDR technology for heavy

vehicles and classified Safety Recommendation H-02-35 to the SAE “Open—Acceptable

Response” on March 19, 2004.

In December 2003, the SAE issued Surface Vehicle Recommended Practice J1698,

which established a standard format for displaying and presenting crash-related data

recorded or stored by electronic components that are already installed in many light-duty

vehicles. The format applies specifically to the postevent format of downloaded data and

does not direct how data should be collected or which vehicle systems should be

monitored. The recommended practice addresses some 70 data elements. The SAE has

stated that it continues to develop Surface Vehicle Recommended Practice J1698/2

“Vehicular Data Extraction,” which will address the collection of event data.

On June 4, 2004, the IEEE completed its work on a proposed “Standard for Motor

Vehicle Event Data Recorders.” This voluntary EDR standard for highway vehicles will

be available throughout the 175 nations that accept IEEE standards. It is scheduled to go

before the IEEE Standards Association in September 2004 for final adoption.

29 National Transportation Safety Board, Motorcoach Run-Off-the-Road Near Canon City, Colorado,

Highway Accident Brief NTSB/HAB-02/19 (Washington, DC: NTSB, 2002).
Factual 32 Highway Accident Report

NHTSA issued a Notice of Proposed Rulemaking (NPRM) concerning EDRs on

June 10, 2004. In it, the agency stated:

Manufacturers have been voluntarily installing EDRs as standard equipment in

increasingly larger numbers of light vehicles30 in recent years. They are now being

installed in the vast majority of new vehicles. The information collected by EDRs

aids investigations of the causes of crashes and injuries, and makes it possible to

better define and address safety problems. The information can be used to

improve motor vehicle safety systems and standards. As the use and capabilities

of EDRs increase, opportunities for additional safety benefits, especially with

regard to emergency medical treatment, may become available.

We are not presently proposing to require the installation of EDRs in any motor

vehicles. We are proposing to (1) require that the EDRs voluntarily installed in

light vehicles record a minimum set of specified data elements useful for crash

investigations, analysis of the performance of safety equipment, e.g., advanced

restraint systems, and automatic collision notification systems; (2) specify

requirements for data format; (3) increase the survivability of the EDRs and their

data by requiring that the EDRs function during and after the front, side and rear

vehicle crash tests specified in several Federal motor vehicle safety standards; (4)

require vehicle manufacturers to make publicly available information that would

enable crash investigators to retrieve data from the EDR; and (5) require vehicle

manufacturers to include a brief standardized statement in the owner’s manual

indicating that the vehicle is equipped with an EDR and describing the purposes

of EDRs.

30 As defined in the NPRM, light vehicles include passenger cars, multipurpose passenger vehicles, and

trucks and buses with a GVWR of 8,500 pounds or less and an unloaded vehicle weight of 5,500 pounds or

less.
33 Highway Accident Report

Analysis

In the following analysis, the Safety Board will first exclude factors that neither

caused nor contributed to the accident and then examine those factors that led to or had a

role in the accident. The discussion that follows will focus on the accident driver’s

unintended acceleration, the adequacy of temporary traffic control measures for the

protection of pedestrian traffic in the SMCFM, and the need to equip motor vehicles with

EDRs.

Exclusions

The weather was clear and dry on the afternoon of the accident; the sun was almost

directly overhead, indicating that visibility issues apparently did not affect the driver’s

performance. Postaccident examination of the 1992 Buick LeSabre by both the CHP and

Safety Board investigators revealed no mechanical defects or conditions that would have

caused the vehicle to accelerate in an uncontrolled manner. Therefore, the Safety Board

concludes that neither weather conditions nor the mechanical condition of the vehicle

contributed to this accident. 

The driver had lived in the Los Angeles-Santa Monica area for more than 70 years

and had owned the accident vehicle for more than 10 years. The SMCFM had taken place

at the same location and on the same day of the week for 21 years and, although he had not

patronized the market for a few years, the driver had some familiarity with it and indicated

in his statement to police that he visually identified it ahead of him on Arizona Avenue.

Therefore, the Safety Board concludes that the driver’s experience and familiarity with his

vehicle and the area of the farmers’ market were not factors in this accident. 

Toxicological testing by the Los Angeles County Sheriff’s Department was

negative for alcohol, amphetamines, barbiturates, benzodiazepines, cannabinoids, cocaine,

opiates, and phencyclidine. A review of the driver’s medical and prescription drug records

indicated that the driver had not been prescribed medications that would have adversely

affected his ability to operate a motor vehicle. Therefore, the Safety Board concludes that

neither alcohol, nor illicit drugs, nor the driver’s use of prescription medications was a

factor in this accident. 

Only limited information on the driver’s usual sleep habits and rest, particularly

during the 72 hours preceding the accident, could be obtained from police interviews of

the driver and his wife. However, the circumstances of the accident and eyewitness

accounts of the driver’s behavior during the accident sequence do not indicate that the

driver fell asleep or that his judgment or performance were fatigue-impaired. The driver’s

statements to the SMPD and the press suggest that he was alert, aware, and cognizant of

what was happening throughout the accident sequence, beginning with his departure from
Analysis 34 Highway Accident Report

the post office, through the period of unintended acceleration, and continuing to the point

at which the vehicle came to rest and he was taken into custody. Therefore, the Safety

Board concludes that neither insufficient sleep nor fatigue was likely to have had a role in

this accident. 

The separation between the accelerator and brake pedals was 2 inches at the

closest point. Many studies have been conducted on the size, shape, and placement of

automobile pedals; the consensus is that a minimum horizontal separation of 50 mm and a

vertical separation of 50.8 mm (2 inches) are necessary.31

The primary concern about pedal placement is dual activation, that is, the driver

depressing both the accelerator and the brake when he or she only intends to depress one

or the other. The pedal separation in the accident vehicle was at the recommended

minimum,32 and two factors suggest that dual activation did not occur in this accident.

First, witnesses reported they did not see the vehicle’s brake lights illuminate, which

would have occurred if the brake pedal had been depressed, even in conjunction with the

accelerator. Second, witness descriptions of the vehicle’s motion and the physical

evidence indicated significant increases in acceleration and speed during the accident

sequence and did not indicate a retarding force, which would be expected if the brake

pedal had been depressed.

Moreover, the Safety Board notes that the 1992 Buick LeSabre does not have a

history of pedal problems since its production. Data maintained by NHTSA would

probably indicate whether the horizontal separation between the vehicle’s pedals has

resulted in pedal misapplication errors or unintended acceleration more frequently than

expected. Furthermore, the driver had owned and operated the accident vehicle for 10

years and thus was familiar with the placement and operation of the Buick’s pedals.

Absent evidence that the 1992 Buick LeSabre was predisposed to pedal misapplication

errors or unintended acceleration and in light of physical evidence, witness accounts of the

vehicle’s motion during the accident sequence, and the driver’s familiarity with the

vehicle, the Safety Board concludes that the horizontal separation of the pedals in the

vehicle neither caused nor contributed to this accident. 

The driver stated that he was aware that he was entering the farmers’ market. He

made steering inputs while driving through the market, but he apparently failed to

recognize that he was depressing the wrong pedal and to correct his error. A

comprehensive review of the driver’s medical records disclosed no evidence of a medical

condition that would have accounted for or contributed to these circumstances. 

31 For example, see Joint Army-Navy-Air Force Steering Committee, Human Engineering Guide to

Equipment Design (New York: John Wiley & Sons, 1972); J. Weiman, Handbook of Ergonomics and

Design Factors (New Jersey: Prentice Hall, 1993); J.A. Adams, Human Factors Engineering (New York:

MacMillan Press, 1989); and S. Konz, Work Design: Industrial Ergonomics (Worthington, OH: Publishing

Horizons, Inc., 1990).

32 Pedal separation is also a consideration in reducing brake response times; an increase in the distance

between pedals is associated with a corresponding increase in time to make a brake application. 
Analysis 35 Highway Accident Report

Although the driver had a significant history of orthopedic conditions affecting his

lower spine and legs, and although he had been issued a disabled parking placard due to

“severe hip arthritis” and associated limitations in mobility, the circumstances of the

accident do not appear to have been associated with these conditions. The driver had been

issued his disabled parking placard in 1994 and subsequently underwent surgery to replace

his left hip and to revise an earlier right hip replacement. The driver’s medical records

document no persistent problems postoperatively, a finding that is consistent with research

on human performance following hip replacement.33 While the driver used a cane, at

times, to walk, evidence does not indicate that his general ability to move his hips and legs

in order to operate the accelerator and brake pedals was impaired. In fact, the driver was

able to maneuver effectively, only moments before the accident, to deposit a letter from

the passenger side window into the curbside receptacle at the post office. Finally, the

absence of other medical conditions that might indicate impaired cognitive function; of a

tendency toward syncope (fainting), near-syncope, or loss of consciousness; and of other

impairment or incapacitation suggests that the driver’s health was not a factor in this

accident.

Therefore, the Safety Board concludes that, although the driver had a history of

medical treatment for orthopedic conditions, neither these conditions nor his general

health were likely to have been a factor in this accident. 

Unintended Acceleration

During postaccident inspection of the Mercedes, Safety Board investigators found

minor contact damage, consisting of horizontal surface scratching to the rear bumper cover.

This minimal level of damage is consistent with witness statements indicating that the Buick

was traveling at a comparatively low rate of speed when it struck the Mercedes, even though

it attained much higher speeds as it accelerated away from the point of initial collision.

The accident vehicle’s high-speed acceleration after it struck the Mercedes may

have given the appearance of a “hit-and-run” incident, as some witnesses believed was the

case. However, the available evidence does not support such an interpretation. Some

witnesses, for example, observed the vehicle decelerate, as well as accelerate, as it

proceeded through the market, and the driver himself told police that he did not recall

striking the Mercedes. He also had no record of reckless or aberrant behavior over many

years as a licensed driver. Moreover, even if he realized that he had struck the Mercedes,

the accident driver is highly unlikely to have made a conscious decision to enter a

crowded market area, thereby endangering his own life and the lives of many others, to

flee the scene of a comparatively minor collision.

33 See, for example, S.B. Ganz, A.Z. Levin, M.G. Peterson, and C.S. Ranawat, “Improvement in

Driving Reaction Time After Total Hip Arthroplasty,” Clinical Orthopaedics Vol. 413 (2003): 192-200; P.P.

Gogia, C.M. Christensen, and C. Schmidt, “Total Hip Replacement in Patients With Osteoarthritis of the

Hip: Improvement in Pain and Functional Status,” Orthopedics Vol. 17, No. 2 (1994): 145-150; and

W. MacDonald and J.W. Owen, “The Effect of Total Hip Replacement on Driving Reactions,” Journal of

Bone and Joint Surgery (British Volume), Vol. 70, No. 2 (1988): 202-205.
Analysis 36 Highway Accident Report

A more plausible explanation of the circumstances of this accident is that the

driver unintentionally accelerated his vehicle. A human performance analysis of

unintended acceleration needs to account for two behaviors: the driver’s inadvertent

activation of the accelerator and the driver’s subsequent failure either to recognize the

initial mistake or to correct it.34 The factors underlying unintended acceleration are

described below.

Inadvertent Activation

Moving the foot to the accelerator instead of the brake is a well-documented, but

rare occurrence, accounting for 0.03 percent of the accidents reviewed in one study.35

Drivers press the wrong pedal either due to an error in response choice or an error in

response execution.

Errors in response choice entail making the wrong choice when presented with

alternatives. This kind of error is probably not a major factor in unintended acceleration,

since drivers almost always make the correct conscious choice about which pedal they

intend to press. In this accident, the driver of the Buick said he intended to apply the brake

pedal and, in fact, believed he had.

Errors in response execution involve making the correct choice—for example, to

press the brake—but failing to execute the response effectively. In the case of braking,

factors affecting execution include response force (the more force used, the greater the

variability in the movement), response time (the faster the movement, the greater the force

needed), limb size (the larger the limb, the more variability in the motion), head and body

position (if the head or body is out of position, the normal, habitual movement may result

in an error), direction of gaze (looking to the right or left when executing the movement

may introduce error), and negative transfer from other vehicles (the learned movement in

one vehicle may produce an error in another), to name a few.

This accident sequence began when the Buick struck the Mercedes before entering

the farmers’ market. As the traffic light on Arizona Avenue at Fourth Street changed from

red to green, the driver of the Mercedes, which had stopped at the red light, and the driver

of the Buick, which was behind the Mercedes and may not have slowed or stopped,36 both

expected to proceed. As the Mercedes driver began moving into her turn, the movement

would have served as a cue to the accident driver that traffic was about to resume flowing.

However, the Mercedes driver observed pedestrians in the crosswalk and halted her

turning maneuver. This action—stopping on a green light (especially after beginning to

proceed)—would have violated the expectancy of the Buick driver. From his vantage

point behind the Mercedes, the Buick driver had no reason to anticipate the Mercedes’

34 R. Schmidt, “Unintended Acceleration: A Review of Human Factors Contributions,” Human Factors

Vol. 31, No. 3 (1989): 345-364.

35 U.S. Department of Transportation, NHTSA, Analyzing the Role of Driver/Vehicle Incompatibilities

in Accident Causation Using Police Reports, Technical Report HS-801-858 (Washington, DC: NHTSA,

1976).

36 Evidence was insufficient to allow investigators to determine whether the accident driver slowed or

stopped before reaching the Mercedes.
Analysis 37 Highway Accident Report

sudden stop. If his attention was focused on the movement of the Mercedes rather than on

the pedestrians to the right, the Buick driver would have lacked advance warning of both

the impending conflict between the pedestrian traffic and the Mercedes and the resulting

braking by the Mercedes driver. This lack of advance warning, coupled with the possible

violation of expectancy, would have created a situation conducive to human error. 

Moreover, shortly before his vehicle struck the Mercedes, the Buick driver had

deposited a letter in a curbside mailbox less than a block away. He had done so while

remaining inside the automobile, requiring that he maneuver across the seating area and

place the letter through the passenger-side window and into the outside receptacle. Thus,

the accident driver may have been slightly out of position as he resumed driving toward

the Fourth Street intersection. As noted above, one factor that can contribute to an error in

response execution (such as applying one’s foot to a pedal) is having the body out of

position, in which case normal or habitual movement can result in a mistake. 

Rear-end crashes at intersections where a vehicle ahead is stopped represent a

majority of all rear-end crashes in which the struck vehicle is stopped (as opposed to rearend collisions in which both vehicles are in motion).37 Research indicates that a violation

of driver expectancy can account for many accidents involving turning movements, and

usually the actions of other drivers, rather than roadway geometry, are what violate

expectancies.38 When a driver slows or comes to a stop to turn, the following driver may

be unprepared for the vehicle in his or her path, and a rear-end collision may ensue. Such

situations frequently give rise to a hypervigilant reaction, or panic, on the part of the

following driver, and human performance under hypervigilant conditions is generally less

reliable than it is otherwise.

Hypervigilant Reactions (Panic)/Perceptual Narrowing. This term describes

situations in which an individual is exposed to a strong, startling stimulus, sometimes

perceived as life-threatening, accompanied by the perception that a solution must be found

quickly. This combination of stimulus and perception can cause a temporary impairment

of cognitive function; often, the individual appears to freeze, taking no action at all

because his or her internal information processes are overloaded. The individual’s

attention narrows to the stimulus, and all other cues are missed. Some studies39 have

37 T. A. Dingus, S.K. Jahns, A. D. Horowitz, and R. Knipling, “Human Factors Design Issues for Crash

Avoidance Systems,” in Human Factors in Intelligent Transportation Systems, W. Barfield and T.A. Dingus,

eds. (Hillsdale, NJ: Lawrence Earlbaum Associates, 1998).

38 R. Storm, “Pavement Markings and Incident Reduction,” The 2000 MTC Transportation Scholars

Conference, Ames, IA, 2000.

39 See, for example, E.G. Beier, “The Effect of Induced Anxiety of Flexibility of Intellectual

Functioning,” Psychological Monographs Vol. 65, No. 326 (1951); M.M. Burkun, H.M. Bialek, R.P. Kern,

and K. Yagi, “Experimental Studies of Psychological Stress in Man,” Psychological Monographs Vol. 75,

No. 534 (1962); H.H. Kelly, J.C. Condry, A.E. Dahlke, and A.T. Hill, “Collective Behavior in a Simulated

Panic Situation,” Journal of Experimental Social Psychology Vol. 1 (1965): 20-54; R.S. Weinberg and V.V.

Hunt, “The Interrelationships Between Anxiety, Motor Performance, and Electromyography,” Journal of

Motor Behavior Vol. 8 (1976): 219-224; R.S. Weinberg and J. Ragan, “Motor Performance Under Three

Levels of Trait Anxiety and Stress,” Journal of Motor Behavior Vol. 10 (1978): 169-176; and W.D. Fenz and

G.B. Jones, “Individual Differences in Physiological Arousal and Performance in Sport Parachutists,”

Psychosomatic Medicine Vol. 34 (1972): 1-8.
Analysis 38 Highway Accident Report

shown simplistic reasoning and thinking, primitive motor control, and strong emotions

among individuals who are in a hypervigilant state. Due to stress, this hypervigilant state

can set the stage for a habitual response.

Habitual Responses Under Stress. When expectancies are violated and a driver

suddenly perceives a dangerous situation, for example, an impending collision, the driver

is placed under stress and may revert to a generic or habitual response, such as hard

braking. Actions executed under stressful conditions, coupled with limitations on the time

that the driver has to respond, can result in error. Under such conditions, an individual may

attempt to emit more than one response simultaneously40—in the case of the accident

driver, moving the foot to the brake pedal (the reasoned response) while simultaneously

attempting to exert force on the pedal (the habitual response). The driver may not realize

he has performed these responses in parallel, rather than serially, as intended. To

complicate matters further, because the driver believes his or her foot is already on the

brake when it is, in fact, on the accelerator, “hard braking” produces more acceleration.

The unexpected acceleration again violates the driver’s expectancy, producing more

stress, and so on.

In statements to police, the accident driver indicated that he might have gotten the

brake and the accelerator confused. These statements show the driver was aware that he

needed to stop his vehicle, knew that braking was the appropriate response, and attempted

to execute that response, thereby eliminating an error in response choice as a potential

factor. Therefore, the Safety Board concludes that the accident driver made an error in

response execution, inadvertently accelerating when he intended to brake, that resulted in

the collision with the Mercedes Benz. 

Error Detection and Correction

Although unintended acceleration is a rare phenomenon, the failure to detect

inadvertent activation of the accelerator is comparatively common, explaining why drivers

frequently insist they were pressing the brake when, in fact, they were pressing the

accelerator.41 This detection failure may result from the limited feedback provided after

the response is executed. Among the human factors concepts that help account for the

error are “efference copy”42 (the brain orders a response and erroneously assumes it will

be correctly executed) and selective attention (the driver, as a consequence of paying

attention to the environment, steering, shifting, and so forth, is never able to verify the

foot’s actual position). Admittedly, such factors, regardless of their validity, fail to explain

40 A situation similar to that described by Kantowitz in B.H. Kantowitz, ed., “Double Stimulation,”

Human Information Processing (Hillsdale, NJ: Lawrence Earlbaum Associates, 1974).

41 Schmidt (1989).

42 Efferent neural signals arouse or stimulate the muscles. When a neural signal or motor command

produces certain sensory consequences with reasonable consistency, that consistency can make it

unnecessary for the brain to conduct detailed sensory feedback processing. The term “efference copy” refers

to what happens when the body sends a “copy” or duplicate of a frequently sent command to a body part (a

limb, for example) to the sensory part of the brain in lieu of independent feedback from the actual response

(for example, a limb movement). In other words, the intent is misperceived as the effect.
Analysis 39 Highway Accident Report

why the driver is not alerted to the mistake by the difference in expected vehicle position

and dynamics when pressing the brake. But the fact that this difference again violates the

driver’s expectancies may at least partly account for the failure to immediately

comprehend the incongruities.

Reaction times in simulated braking situations are on the order of 0.5 seconds.

Unintended acceleration, however, can persist for as long as 12 seconds.43 In this

accident, the driver proceeded for approximately 2 1/2 blocks before coming to rest, some

10 seconds later. Thus, the driver’s delay in correcting his initial error is consistent with

prior findings on unintended acceleration.

The driver knew that he needed to brake and said that he attempted to do so.

Instead, he pressed the accelerator pedal, propelling his vehicle into the Mercedes, through

the intersection, and into the farmers’ market. The fact that he did not detect his response

execution error, which resulted in the unintended acceleration, may have been due to

sensory processing errors, selective attention, violated expectancies, or a combination of

some or all of these factors. The Safety Board concludes that the driver of the 1992 Buick

failed to detect his error in response execution, thereby inadvertently accelerating his

vehicle and propelling it through the SMCFM. 

The witness descriptions of a racing engine, as the Buick continued to accelerate

through the market, are consistent with an habitual driver response. As the driver’s stress

level rose and he focused on trying to stop his vehicle, he probably reverted to the habitual

response of hard braking, but did so before he had moved his foot from the accelerator to

the brake pedal. When he perceived that “hard braking” was not working, the driver

probably tried to “pump” his brakes—a trained response and one that suggests he was

selectively focused on stopping. Because his foot was on the accelerator rather than the

brake, the result would have been “revving” or racing of the engine and acceleration of the

vehicle. One witness reported that the Buick appeared to accelerate in response to striking

various objects; such acceleration is consistent with more forceful application of the

accelerator pedal—or, in the mind of the driver, more forceful brake applications.

Additionally, the driver stated that he attempted to move the column transmission shift

into park, a maneuver that would have further distracted his attention from the foot pedals.

Efforts to move the vehicle immediately after the accident prevented the police or Safety

Board investigators from determining what gear the Buick was in when it stopped.

The Safety Board concludes that the accident driver most likely reverted to the

habitual response of hard braking or “pumping” the brakes as his stress level increased

and the vehicle failed to slow, but because his foot was on the accelerator rather than the

brake pedal, this response led to increased acceleration. The Safety Board further

concludes that the ineffectiveness of the accident driver’s efforts to stop his vehicle and

the realization that he was striking objects in his path very likely increased the already

high level of stress affecting him, thereby impeding his ability to quickly detect and

correct his earlier response execution error. 

43 Schmidt (1989).
Analysis 40 Highway Accident Report

Although the accident resulted from the driver’s error in response execution and

his failure to detect that error, Safety Board investigators were unable to gather sufficient

information to determine with certainty whether the 86-year-old driver’s age or use of

nonprescription medications contributed to this accident. Neither the CHP or the SMPD

cooperated with the Safety Board’s investigation, and both declined to provide the Board

with needed accident-related information, including witness and driver identities or

statements, toxicological specimens, and on-scene data, until 6 months after the collision.

As a result, the Safety Board conducted its investigation without the involvement of the

police and without the access to certain critical and perishable information that the police

had collected.

Older drivers are generally more susceptible to conditions that diminish cognition,

perception, and physical reaction. An examination of the driver’s medical history revealed

that neither his orthopedic conditions, which affected his lower spine and legs, nor his

general health were likely to have been factors in this accident. However, Safety Board

investigators were denied access to the driver and, therefore, were unable to further

evaluate his performance capabilities at the time of the accident.

Safety Board investigators were also unable to obtain a specimen of the driver’s

blood from the police, who tested for illicit drugs and prescription medications but did not

test for nonprescription medications. Consequently, whether the driver used

nonprescription medications, and, if he did, the possible effect on this accident are

unknown. The Safety Board has found in previous investigations that over-the-counter

medications can have detrimental effects on driver performance. The Board routinely tests

toxicological specimens for evidence of the presence of such medications, which are not

typically part of police-related toxicological testing. The Safety Board concludes that the

contributions of the 86-year-old driver’s age and use of nonprescription medications, if

any, to his error in response execution and to his failure to detect that error could not be

determined. 

Adequacy of Temporary Traffic Control 

When the Wednesday and Saturday SMCFMs were not in operation, Arizona

Avenue was a through collector roadway open to vehicular traffic. Street closure to

accommodate the SMCFMs involved a complex section of an urban collector road that

included intersecting streets, alleyways, and traffic signals. Santa Monica was responsible

for the maintenance and safety oversight of Arizona Avenue; it also sponsored and

operated the two other farmers’ markets located elsewhere, for a total of four, in the city.

Each week, city contractors restricted vehicular traffic on Arizona Avenue by erecting

traffic control devices based on a 1986 temporary traffic plan for the farmers’ market. The

temporary traffic plan failed to provide barriers and allowed vehicular traffic from the

alleyway between Second and Third Streets to flow unimpeded into the pedestrian zone.

The full closures on Arizona Avenue at the alley between Third and Fourth Streets,

as well as the Second Street closure, had only type I and A-frame plastic barricades in
Analysis 41 Highway Accident Report

place, although the CTM,44 the WATCH manual, and the MUTCD all recommend type III

barricades. Furthermore, as this accident demonstrated, the barricades erected at the time

provided no positive or rigid barrier between vehicular and pedestrian traffic along

Arizona Avenue or any of the intersecting streets. In addition, Santa Monica apparently

never recognized that, although Arizona Avenue was closed during the operation of the

SMCFM, the traffic signals at the Second and Third Street intersections continued to

operate on a normal green-yellow-red cycle, potentially providing motorists who were

looking beyond the road closures, or who could not see them because of traffic, with

conflicting signals.

The SMCFM on Arizona Avenue had been operating since 1981; however, Santa

Monica had not revised or updated the traffic plan since 1986. Thus, the city apparently

had not compared the traffic plan with its own internal guidance or with State and Federal

guidance regarding temporary road closures.

At the time of the accident, Santa Monica indicated that it used the WATCH

manual to determine what traffic controls should be in place for temporary street closings

in the city. But the temporary traffic control devices erected on Arizona Avenue during

operation of the SMCFM did not conform to the guidelines in this handbook. During street

closures, the handbook called for two ROAD CLOSED signs mounted on type III

barricades and advance warning signs on the approaches to the closed road. Figure 13

depicts the traffic controls that probably would have been in place for the SMCFM, had

Santa Monica complied with its own traffic control handbook.

The CTM and the MUTCD were also available to the city’s Transportation

Management Division before the accident. The CTM sets forth basic principles governing

the design and use of traffic control devices for all streets and highways open to public

travel in California. It also specifically requires protection of pedestrians and workers in

temporary traffic control areas. Both the CTM and the MUTCD call for ROAD CLOSED

signs, advance warning signs, at least [emphasis added] type III barricades, and optional

detour and route marking signs. Figure 14 depicts the probable traffic control plan that

would have been in place, had Santa Monica complied with State and Federal guidelines.

Thus, Santa Monica failed to comply not only with its own guidance, but also with

State and Federal guidelines regarding temporary road closures for the SMCFM. As a

result, the temporary traffic control devices erected along Arizona Avenue at the time of

the accident did not provide the more robust barricades recommended in city, State, and

Federal manuals and sent conflicting messages to motorists by, for example, allowing

traffic signals at Second and Third Streets to function, even though the road was not open

to through traffic. While the signage is unlikely to have affected the accident driver’s

actions, it could be critical in another situation in which a driver is impaired or distracted

and does not understand that Arizona Avenue is closed to vehicular traffic. 

44 Section 5-05.6, “Channelizing Devices.”
Analysis 42 Highway Accident Report

Figure 13. SMCFM traffic control measures that comply with city guidelines.
Analysis 43 Highway Accident Report

The Safety Board therefore concludes that the city’s temporary traffic plan for

closure of Arizona Avenue to accommodate the SMCFM was not consistent with

established local, State, or national guidelines and was inadequate to ensure the safe flow

of vehicular and pedestrian traffic in the area. The temporary traffic control plan for the

market had been developed more than 2 decades ago and revised only once 5 years later.

Since the 1986 revision, both the CTM and the MUTCD were updated several times.

Figure 14. SMCFM traffic control measures that comply with CTM and MUTCD guidelines.
Analysis 44 Highway Accident Report

Considering the changes in traffic engineering guidelines and practices, as well as local

traffic patterns and volumes, over time, the Safety Board believes that Santa Monica

should update its temporary traffic plans for roadway closures to ensure the safe operation

of its certified farmers’ markets and should review and evaluate the adequacy of the plans

annually. 

Additional signs and type III barricades alone would not have prevented the

accident vehicle from entering the pedestrian zone in the SMCFM. The premise

underlying the use of such barricades, as well as the guidance provided in the WATCH

manual, the CTM, and the MUTCD, is that the road closures in question are indeed

temporary situations. However, the SMCFM was a regularly recurring, albeit intermittent,

event and, thus, different from the typical one-time work areas addressed in the guides.

The Arizona Avenue road closure for the Wednesday SMCFM had occurred twice each

week for more than 20 years and was therefore a sustained and predictable operation.

Furthermore, encouraging patrons of the SMCFM and other pedestrians to occupy

the roadway when it was closed should have led city officials to consider measures to

protect those pedestrians from vehicular traffic. Following the accident, vendors in the

SMCFM, recognizing the need for more substantial protection from errant vehicles,

moved their personal vehicles to block access to Arizona Avenue. Although the vendors’

intent was to provide a barrier between traffic and the market, vehicles are not generally

an appropriate countermeasure for this purpose. Vehicles are not specifically designed to

absorb a collision from, or to redirect, an errant vehicle, and they contain flammable

liquids and components. When vehicles are used for such purposes, for example, in

mobile work zones, they are typically equipped with crash attenuating devices. In

situations such as the SMCFM, however, other, more appropriate options for positive

separation are available to protect pedestrians from errant vehicles.

Segregating pedestrian from vehicular traffic is a key element in pedestrian safety.

Positive barriers between pedestrians and vehicles, although not always viable, are the

best method of ensuring this segregation. During temporary road closures, the nature,

frequency, and duration of the closure does not always allow for durable positive barriers.

However, in situations such as the SMCFM, which took place every Wednesday and

Saturday, the temporary closure was scheduled, recurring, and of sufficient duration to

warrant use of positive barriers. A positive rigid barrier system would very likely have

prevented the accident vehicle from intruding into the pedestrian area.

Santa Monica recognized the need for and value of positive, rigid barriers to

protect pedestrians when the city installed removable bollards on the Third Street

pedestrian promenade (see figure 10). Metal bollards at the entrances along Arizona

Avenue protect the Third Street promenade, a dedicated pedestrian mall that was once a

through street. The bollards, while designed to be permanently placed in the roadway, can

also be lowered to allow passage of traffic, if necessary. By providing a rigid, positive

separation between vehicles and pedestrians, bollards reduce the likelihood of vehicular

incursion into pedestrian traffic areas.
Analysis 45 Highway Accident Report

Other jurisdictions have also recognized the utility of such barriers in protecting

pedestrians during temporary road closures. For example, in the early 1980s, the New

Orleans city council passed an ordinance making Bourbon Street a pedestrian mall during

nighttime hours. To protect pedestrians on the closed street, the city placed removable

bollards in the roadway. The Bourbon Street bollards, which extend about 40 inches above

ground and 6 inches into the ground, are placed into metal collars embedded in the

roadway. According to the traffic engineer for the city’s Department of Public Works,

New Orleans does not keep records of the bollards’ effectiveness in stopping errant

vehicles from entering the pedestrian mall. However, the poles are often bent and need to

be replaced, showing that they have successfully deterred vehicles from entering the

closed area.

The Roadside Design Guide does not specifically reference bollards. Santa Monica

indicated that it did not consider bollards for the SMCFM because the road closure for the

farmers’ market was not permanent. However, as the New Orleans experience

demonstrates, rigid barriers can be utilized effectively for recurrent, temporary road

closures. Therefore, the Safety Board concludes that had Santa Monica installed a

temporary rigid barrier system, such as bollards, at the closure limits of the SMCFM, the

barrier system might have arrested or reduced the forward motion of the accident vehicle,

thereby preventing it from continuing into the farmers’ market and eliminating or greatly

reducing the number of casualties. The Safety Board believes that Santa Monica should

install a temporary rigid barrier system at the closure limits of the SMCFM to provide a

physical barrier to errant vehicles entering the market. 

Currently, the MUTCD provides guidance on the use of additional

countermeasures, such as concrete traffic barriers or crash cushions, to protect pedestrians.

Additionally, the Roadside Design Guide, referenced in the MUTCD, discusses the design

and application of such countermeasures. However, the majority of the information

presented in both the MUTCD and the Roadside Design Guide focuses on work zones.

While the countermeasures in question may also be deployed for other types of street

closures, the references and information in the guides have a strong enough emphasis on

work zones that users may have difficulty recognizing their applicability to other

situations. For example, the Roadside Design Guide’s section on traffic barriers specifies

“work-zone traffic barriers” as it begins its discussion of the subject. Similarly, chapter

6B.01 of the MUTCD states: “The control of road users through a temporary traffic

control zone shall be an essential part of highway construction, utility work, maintenance

operations, and incident management.” 

Although the principles of incident management set forth in the MUTCD and

related guidance are intended to apply equally to road closures for events such as the

SMCFM, parades, and similar activities, that intent is not highlighted and may be

overlooked. Therefore, the Safety Board concludes that the MUTCD’s guidance on

temporary traffic control is insufficiently clear to ensure that users will apply it to road

closures not associated with highway construction or maintenance. The Safety Board

believes that the FHWA should revise the Manual on Uniform Traffic Control Devices,

Chapter 6, “Temporary Traffic Control,” to provide specific references and guidance on
Analysis 46 Highway Accident Report

the use of barricades, barriers, crash cushions, and other devices, as appropriate, for road

closure situations other than highway construction or maintenance. The Safety Board will

inform AASHTO, the American Public Works Association, the U.S. Conference of

Mayors, the National Association of Counties, and the National Association of Towns and

Townships of the circumstances of this accident, emphasizing the importance of physical

barriers, as well as periodic reviews of traffic control plans, in protecting the public at

farmers’ markets and similar events. 

Event Data Recorders 

Had the accident vehicle been equipped with an EDR, the recorder would probably

have collected valuable information about this accident. Driver and witness statements

indicate that an unintended acceleration, initiated by pedal misapplication, most likely led

to the accident. However, precise information about the Buick driver’s actions before and

during the collision with the Mercedes is unavailable. Similarly, the driver’s precise

actions—for example, whether he steered, braked, or accelerated—while traversing the

farmer’s market are not known. Additionally, how the vehicle was finally brought to a stop

cannot be determined. While preliminary observations suggested that the driver’s age or

medical condition might have contributed to the accident, no age-related or medical

factors were identified during the investigation. As a result, determination of the cause of

the accident driver’s actions had to be based on analysis of the limited investigative

information, such as witness statements, available. Therefore, the Safety Board concludes

that, had the accident vehicle been equipped with an event data recorder, a significantly

higher level of science could have been applied to assessing and understanding the

driver’s behavior, as well as its contribution to this accident and the broader issue of

unintended acceleration.

As in most accidents, the role of human factors in the Santa Monica accident could

not be definitively determined or completely understood. By providing more comprehensive

data on driver performance and behavior, EDRs assist safety researchers, accident

investigators, and automotive designers in developing effective means for preventing similar

occurrences. Better information about driver inputs and responses helps researchers

understand whether certain brake and throttle geometry relationships affect the accident rate

and whether certain drivers are at higher risk for performance-related accidents.

In addition, by providing prompt and impartial crash-related information, EDRs

benefit law enforcement personnel, who are responsible for determining the facts and

circumstances of highway accidents. Manufacturers can also use such data to improve

vehicle design and to assist in the diagnosis of vehicle systems. EDR data have value for

the health care community, which can base on-site injury triage decisions on more

accurate and complete information, and assist in the deployment of appropriate emergency

services by triggering automated systems that alert responders to the nature of an incident.

Private vehicle owners have access to EDR information on how their vehicles have been

operated and whether vehicles have been in previous crashes. Thus, vehicle EDRs provide

qualitative and quantitative information critical to improving highway safety. 
Analysis 47 Highway Accident Report

Recent integration of the event recording function with the crash detection and

deployment functions of automotive air bag system controls has provided a hitherto

unavailable source of unbiased, factual information. Some U.S. vehicle manufacturers

have integrated limited event recording capability into their products by including this

functionality in the vehicle’s air bag control system. However, the parameters recorded

and the manner in which the data are accessed are not uniform. Through years of

experience with EDRs in the aviation, rail, and marine modes of transportation, the Safety

Board and the transportation industry have learned a great deal about the effective

integration and use of recording technology. Establishing industry standards for recording

in these modes has been critical to effective EDR implementation. Industry standards

ensure consistency and compatibility and prevent the unnecessary and inefficient

proliferation of multiple formats and configurations.

The factors identified in developing event data recording standards for other

modes of transportation provide a basis for formulating highway EDR standards in areas

such as the specific data parameters to be recorded, sampling rates, recording duration,

data extraction interface configurations, and data storage formats. Additionally, data

survivability issues, such as backup power supplies and resistance to fluid immersion,

impact shock, crush penetration, and fire must also be considered. The benefits of industry

standards already realized in other modes of transportation demonstrate the need for

similar EDR standards in the automotive industry. 

NHTSA, the IEEE, and the SAE have efforts under way that provide a

standardization platform to build upon, thereby ensuring that the benefits of EDRs can be

realized quickly and efficiently for all light-duty vehicles. NHTSA’s recently announced

NPRM regarding EDR standards for light-duty vehicles is a welcome step forward and is

necessary to ensure the timely and efficient implementation of EDR technology into the

highway transportation system. In that NPRM, NHTSA has indicated that it does not

propose to require that newly manufactured vehicles be equipped with EDRs. It has also

predicted that 65 to 90 percent of new vehicles will be equipped with EDRs. The Safety

Board is concerned that, unless installation of EDRs is mandatory, collection of national

crash data will be incomplete. Effectively developing and establishing highway safety

policy is dependent on accurate information about the causes of accidents. Collection of

only partial fleet information could undermine the implementation of the most appropriate

and cost-effective highway safety countermeasures. Therefore, the Safety Board

concludes that NHTSA’s proposed rulemaking on standards governing voluntary, rather

than mandatory, installation of EDRs in light-duty vehicles will not result in obtaining the

maximum highway safety benefits from this technology. The Safety Board believes that

once standards for EDRs are developed, NHTSA should require their installation in all

newly manufactured light-duty vehicles. 
48 Highway Accident Report

Conclusions

Findings

1. The weather; the mechanical condition and design of the vehicle, in particular, the

horizontal separation of the control pedals; and the driver’s experience and familiarity

with his vehicle and the area of the farmers’ market were not factors in this accident.

2. Although the driver had a history of medical treatment for orthopedic conditions,

neither these conditions, nor his general health, nor his use of prescription

medications, nor insufficient sleep or fatigue were likely to have been factors in this

accident; test results did not indicate that alcohol or illicit drugs were likely to have

contributed to the accident.

3. The accident driver made an error in response execution, inadvertently accelerating

when he intended to brake, that resulted in the collision with the Mercedes Benz. 

4. The accident driver failed to detect his error in response execution, thereby

inadvertently accelerating his vehicle and propelling it through the Santa Monica

Certified Farmers’ Market. 

5. The accident driver most likely reverted to the habitual response of hard braking or

“pumping” the brakes as his stress level increased and the vehicle failed to slow, but

because his foot was on the accelerator rather than the brake pedal, this response led

to increased acceleration. 

6. The ineffectiveness of the accident driver’s efforts to stop his vehicle and the

realization that he was striking objects in his path very likely increased the already

high level of stress affecting him, thereby impeding his ability to quickly detect and

correct his earlier response execution error.

7. The contributions of the 86-year-old driver’s age and use of nonprescription

medications, if any, to his error in response execution and to his failure to detect that

error could not be determined.

8. Santa Monica’s temporary traffic plan for closure of Arizona Avenue to accommodate

the Santa Monica Certified Farmers’ Market was not consistent with established

local, State, or national guidelines and was inadequate to ensure the safe flow of

vehicular and pedestrian traffic in the area. 
Conclusions 49 Highway Accident Report

9. Had Santa Monica installed a temporary rigid barrier system, such as bollards, at the

closure limits of the Santa Monica Certified Farmers’ Market, the barrier system

might have arrested or reduced the forward motion of the accident vehicle, thereby

preventing it from continuing into the farmers’ market and eliminating or greatly

reducing the number of casualties.

10. The Manual on Uniform Traffic Control Devices’ guidance on temporary traffic

control is insufficiently clear to ensure that users will apply it to road closures not

associated with highway construction or maintenance.

11. Had the accident vehicle been equipped with an event data recorder, a significantly

higher level of science could have been applied to assessing and understanding the

driver’s behavior, as well as its contribution to this accident and the broader issue of

unintended acceleration. 

12. The National Highway Traffic Safety Administration’s proposed rulemaking on

standards governing voluntary, rather than mandatory, installation of event data

recorders in light-duty vehicles will not result in obtaining the maximum highway

safety benefits from this technology. 

Probable Cause

The National Transportation Safety Board determines that the probable cause of

this accident was the failure of the Buick driver to maintain control of his vehicle due to

his unintended acceleration. Contributing to the severity of the accident was the lack of a

barrier system to protect pedestrians in the Santa Monica Certified Farmers’ Market area

from errant vehicles. 
50 Highway Accident Report

Recommendations

To the Federal Highway Administration:

Revise the Manual on Uniform Traffic Control Devices, Chapter 6, “Temporary

Traffic Control,” to provide specific references and guidance on the use of

barricades, barriers, crash cushions, and other devices, as appropriate, for road

closure situations other than highway construction or maintenance. (H-04-25)

To the National Highway Traffic Safety Administration:

Once standards for event data recorders are developed, require their installation in

all newly manufactured light-duty vehicles. (H-04-26) 

To the city of Santa Monica:

Install a temporary rigid barrier system at the closure limits of the Santa Monica

Certified Farmers’ Market to provide a physical barrier to errant vehicles entering

the market. (H-04-27)

Update your temporary traffic plans for roadway closures to ensure the safe

operation of the city’s certified farmers’ markets and review and evaluate the

adequacy of the plans annually. (H-04-28)

BY THE NATIONAL TRANSPORTATION SAFETY BOARD

ELLEN ENGLEMAN CONNERS CAROL J. CARMODY

Chairman Member

MARK V. ROSENKER RICHARD F. HEALING

Vice Chairman Member

DEBORAH A. P. HERSMAN

Member

Adopted: August 3, 2004
51 Highway Accident Report

Appendix A

Investigation and Public Hearing

The National Transportation Safety Board was notified of the Santa Monica,

California, accident on July 16, 2003. The Safety Board dispatched an investigative team

consisting of members from the Washington, D.C., Atlanta, Georgia, and Denver,

Colorado, offices. Groups were established to investigate human performance and

highway, vehicle, and survival factors.

Representatives of the city of Santa Monica participated in the investigation.

No public hearing was held; no depositions were taken.