Drivers express concerns over duration of yellow light
Drivers are concerned about length of yellow light at one intersection in the valley.Photo: Video by ktnv.com
North Las Vegas, NV (KTNV) -- When it comes to the duration of a yellow traffic light, how long is long enough?
A driver emailed Action News concerned that the timing at a North Las Vegas intersection could lead to crashes. At Martin Luther King Boulevard and West Cheyenne Avenue, drivers and pedestrians we spoke with said they believe the yellow turn light is too short.
"You have all this other traffic coming and everything else so I think, just to keep it going smoothly, I think it should be a little bit longer," said Carla Terrell.
We timed the yellow signal to last just under four seconds. The city of North Las Vegas said the official time is four seconds.
"Wow," said driver Karmen Hall. "Yeah, it should be longer."
But should it? We turned to the city for answers.
The city generally follows guidelines from the Federal Highway Administration to time the signals, city spokeswoman Juliet Casey said in an email. Not all intersections are timed the same.
The highway administration recommends a special equation to calculate the appropriate duration of a yellow light, spokeswoman Kelly Dollinger said. The equation, Yellow Time = t + S / (2a +-64.4 g), takes into account factors like speed, reaction time and deceleration.
Congestion may play a role here. The intersection is considered one of the most congested in North Las Vegas, averaging about 64,000 vehicles a day, Casey said.
The intersection also sees an average of 22 crashes a year; however, the number does not include a breakdown on the cause and type of crash, so it's unclear if the yellow timing played any part in those crashes.
For now, drivers face a race against the red light, with four seconds of yellow.