"Where's the Cheese?" is a series of articles addressing Human Factors, their role in safety issues on base and in preventing accidents of all types.
Here at Aerospace and Operational Physiology, we hope everyone had a great Thanksgiving, and an awesome holiday season! I wanted to discuss an issue that you deal with whether you realize it or not.
The issue is driving at night. More specifically, I wanted to discuss the visual limitations that can put you in critical danger if you aren't ready for them.
As humans, we were not designed to operate during hours of darkness. If we were, the light bulb would never have made it into the book of great inventions.
The point is, while behind the wheel, most of what dictates what we are doing with our car comes from visual cues. At night those visual cues decrease dramatically and are centered mostly on what is visible through the headlights.
Headlights usually illuminate only up to 300 feet, and that's with the high beams on. This equals roughly 10 percent of what it usually is during the day.
Depth perception, or how near or far an object is, can be affected due to the lack of contrast on that object. Color recognition can also be affected due to the fact that the cone cells in our eye which are responsible for color vision are no longer being stimulated by light. Instead we are using a mix of photopic (daytime) and scotopic (nighttime) vision called mesopic vision, in which both day and nighttime vision are at work. This is why colors become quite a bit more difficult to discern at night.
Your peripheral vision can also be affected primarily due to the fact that our head lights shine straight ahead.
So what are some things we can do to keep us a little safer behind the wheel at night?
Well for starters, please SLOW DOWN and stay off the cellphone!
Use a scanning technique, keep your eyes moving, and try not to focus on just what is illuminated by the headlights.
Next, beware of the glare. Keep a clean windshield and try not to turn on the interior car lights, like the overhead lights and such.
Also, try not to stare at those oncoming car headlights, as they can really wash out the nighttime vision you had going for you.
Most importantly, keep your situational awareness up and please stay safe behind the wheel at night.
From the 75th AMDS, this is Tech. Sgt "Lucky" Longinotti wishing you a great 2013!