I took a closer look at it this week and noticed something interesting. A number of colorblind-friendly treatments also provided an overall benefit to the safety at signals.
Double Red Lights
- Total crashes down 2 per year
- Angle crashes down 1.7 per year
- Rear-end crashes up 0.5 per year
Advanced Warning Flashers
I had not thought about this one before as a significant colorblind benefit, but I believe it could be. There are times that I don't always know if what I'm seeing three blocks ahead is a traffic signal or just ambient lighting from other sources. Signal Ahead signs (and particularly those discussed in the report with actuated flashers) give me the additional information I need to know what is coming up.
- Total crashes down 1.4 per year
- Angle crashes down 0.7 per year
- Rear-end crashes down 0.6 per year
- Total crashes down 1 per year
- Angle crashes down 0.4 per year
- Rear-end crashes down 0.3 per year
The best implementation plan may be modifying policy so any new signal installations (or updgrades) are put in with these measures. High crash locations could also be added to the mix, so that eventually every signal includes these improvements or something similar.