As I stated originally, with higher speeds, the All-Red time should decrease since it speed and All-Red time is an inverse relationship.
The Institute of Transportation Engineers (ITE) calculations for All-Red are based upon clearing a vehicle through an intersection during the All-Red phase. In my experience most, if not all, jurisdictions allow vehicles to be in an intersection at the start of red.
Philip Tarnoff of the University of Maryland Center for Advanced Transportation Technology did a study based on the delay calculations found in the Traffic Engineering Handbook and found that "neither yellow nor all-red times have a significant impace on capacity, and that all-red time will only have a significant impact on delay under heavy traffic conditions." He did his study based on traffic signals with 2-, 4-, 6-, and 8-phase cycles, and the delay increases significantly as you increase the number of phsaes. I work mostly with 2-, 3-, or 4-phase cycles, so the added safety benefit of having a longer all-red phase usually outweighs the slight increase in delay.
...the timing of the Yellow and All-Red intervals are pretty straightforward. The Yellow should be 3-6 seconds long, and is based upon the approach speeds (the higher the speed, the longer the Yellow). The purpose of the Yellow is warn traffic of an impending change in Right-of-Way assignment. On a typical urban roadway with speeds of 30 mph, the Yellow should be 3 seconds long.
The All-Red interval should also be 3-6 seconds long, and should be based upon the geometry and size of the intersection, as well as the approach speeds. The purpose of the All-Red interval is to ensure that the intersection is clear of crossing traffic prior to assigning the Right-of-Way to a side street or pedestrian crossing. To determine the appropriate length of an All-Red interval, you need measure the distance from the stop line to the far side of the intersection (typically past the far crosswalk) and determine the approach speed. 30 m.p.h. = 44 ft/sec, so if the distance from the stop line to the far crosswalk is 88 feet, the appropriate All-Red interval would be 2 seconds. To be conservative, you can also add the length of a typical vehicle (~25 ft.) into the equation.
With that knowledge in hand, you may be able to fight a red light-running ticket if you believe the timing provided for you was too short. Those are the general guidelines across the US. Individual states, counties, and cities may have different criteria, though.
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As I stated originally, with higher speeds, the All-Red time should decrease since it speed and All-Red time is an inverse relationship. The Institute of Transportation Engineers (ITE) calculations for All-Red are based upon clearing a vehicle through an intersection during the All-Red phase. In my experience most, if not all, jurisdictions allow vehicles to be in an intersection at the start of red. Philip Tarnoff of the University of Maryland Center for Advanced Transportation Technology did a study based on the delay calculations found in the Traffic Engineering Handbook and found that "neither yellow nor all-red times have a significant impace on capacity, and that all-red time will only have a significant impact on delay under heavy traffic conditions." He did his study based on traffic signals with 2-, 4-, 6-, and 8-phase cycles, and the delay increases significantly as you increase the number of phsaes. I work mostly with 2-, 3-, or 4-phase cycles, so the added safety benefit of having a longer all-red phase usually outweighs the slight increase in delay.
Actually, I do work in Massachusetts.
...the timing of the Yellow and All-Red intervals are pretty straightforward. The Yellow should be 3-6 seconds long, and is based upon the approach speeds (the higher the speed, the longer the Yellow). The purpose of the Yellow is warn traffic of an impending change in Right-of-Way assignment. On a typical urban roadway with speeds of 30 mph, the Yellow should be 3 seconds long.
The All-Red interval should also be 3-6 seconds long, and should be based upon the geometry and size of the intersection, as well as the approach speeds. The purpose of the All-Red interval is to ensure that the intersection is clear of crossing traffic prior to assigning the Right-of-Way to a side street or pedestrian crossing. To determine the appropriate length of an All-Red interval, you need measure the distance from the stop line to the far side of the intersection (typically past the far crosswalk) and determine the approach speed. 30 m.p.h. = 44 ft/sec, so if the distance from the stop line to the far crosswalk is 88 feet, the appropriate All-Red interval would be 2 seconds. To be conservative, you can also add the length of a typical vehicle (~25 ft.) into the equation.
With that knowledge in hand, you may be able to fight a red light-running ticket if you believe the timing provided for you was too short. Those are the general guidelines across the US. Individual states, counties, and cities may have different criteria, though.