Coordination of Vehicle Lighting and Markings for Improved Worker Safety

PROJECT SUMMARY According to the National Occupational Research Agenda, front line service workers (FLSWs) in the construction, public safety, and transportation, warehousing and utilities (TWU) sectors make up 13% of the U.S. work force but are involved in 36% of workplace fatalities.

Vehicle collisions with workers located inside and outside their own vehicles are the most common causes of fatalities and an important cross-sector priority (e.g., 37% of on-duty police fatalities are caused by motor vehicle collisions).

The proposed exploratory research is directed toward improving the safety of workers in these three sectors, building upon the research team?s earlier R01 grant on the effectiveness of flashing warning lights for enhancing the safety of FLSWs and using perceptual grouping as a means of conveying visual information to drivers.

A driver has many visual tasks to perform while operating a vehicle in a dynamic and often visually chaotic environment such as a work zone.

Of special importance is the ability to detect potential hazards and identify their position and significance so safe path selection maneuvers can be made.

Because transportation agency vehicles and equipment are often placed in and near a driver?s path, thereby representing a potential hazard, they are usually painted in conspicuous colors and equipped with markings and flashing warning lights to help drivers detect them.

These colors, markings and warning lights usually have distinct designs from those used by police and fire vehicles to help drivers more readily identify their function as separate from emergency operations. For example, no state allows vehicles or equipment to use flashing red lights that would be found on fire trucks.

Notwithstanding, requirements for the visual characteristics of vehicle and equipment color, markings and warning lights vary from state to state and even from municipality to municipality within a state. Except for what should not be done, there are no guiding principles for vehicle and equipment colors and markings.

Current practice aimed at protecting FLSW workers on or near roadways can be characterized as providing bright flashing warning lights to get the attention of oncoming drivers together with perceptual chaos with regard to meaning and significance of the work area activities.

Under these conditions the now alerted driver suspends course of action decisions (e.g., braking or steering maneuver) until the chaos has been resolved. Without converting his/her thoughts into words, the driver wants to know what is going on and what do I need to do?

The time between detection and decision can be many seconds and occasionally the driver makes the wrong decision, possibly leading to injury or death for a FLSW.

We propose to examine how perceptual grouping of flashing warning lights with other features associated with FLSW vehicles, specifically paint and retroreflective colors, affect driver behavior.

Our primary outcome measures will be response time to detect the situation and the incremental time to make a decision, operationally defined as a behavioral response to the situation.

We assert that the shorter the detection time and incremental time exhibited by oncoming drivers, the safer FLSWs will be.