Human Factors is the science of human interaction or reaction with mechanical devices or processes. The CED Transportation Group has forensic engineering expertise relating to human interaction with vehicular accidents. This experience is divided into the following two parts:
Perception and Reaction Time (PRT)
Our engineers use state-of-the-art software that measures the ability to perceive a hazard and then react to that hazard. Drive 3 is a vehicular software program development created by a Ph.D. Psychologist with a vehicular accident reconstruction education. This program compiles a vast majority of perception studies that have been performed and calculated based upon parameters of what a normal reaction time should be considered. By utilizing Drive 3 and other advanced computerized programs, our engineers can calculate the reaction time based upon four factors:
- Perception – The first time a person becomes aware of a hazard
- Identification – Identifying what the hazard is
- Decision – What to do about the hazard
- Action – Physical movement of motor skills to avoid the hazard.
These factors and their input allow our engineers to determine perception reaction times that are based on scientific research.
Visibility most often deals with line of sight of a reported hazard that contributed to an accident. These studies can be divided into three parts; lighting, stationary objects and moving objects. The aspect of lighting most often deals with the amount ,whether there is too much or not enough lighting. Roadway designs can have instances where sunlight is too bright without warning or nighttime where lack of light can be a potential cause of an accident. CED engineers utilize meters and other equipment that can measure the light at accident sites using weather mapping, sun positioning and light produced from such things as headlights and street lights.
Using computerized models and a process called “Time & Distance Analysis”, CED can reconstruct an accident from the time of impact back to the distance and time when a driver would have first become aware of a potential hazard. Armed with the proper data, CED engineers can use time and distance analysis to determine potential hazards and/or contributory aspects of an accident
Human Factors involvement in vehicular accidents is only applicable when it is based upon scientific evidence and research. That is why CED engineers use computerized programs and engineering models to provide accurate results that are based upon accredited science. Moreover, using 3D simulation software, CED can provide a working animation showing what would be visible to the driver during the perception reaction time period and throughout the accident.