TRL were commissioned by Transport for London (TfL) to test a wide variety of innovative cycle signals and layouts, which involved undertaking a range of trials with cyclists and other road users. Four sub-trials were conducted to investigate the reactions of road users to Low Level Cycle Signals (LLCS) at a specially constructed typical ‘urban’ four-arm junction built at TRL’s test track. In the second of the four trials the LLCS were positioned on the same pole as the standard traffic signals and gave an ‘early release’ for cyclists ahead of the vehicle traffic. The trial consisted of ‘control’ and ‘treatment’ experiments, with four different durations of early release in which the LLCS changed to green 2, 3, 4 or 5 seconds earlier than the main signals. These were then compared to the previous trial of LLCS with no early release to understand the relative effect on behaviour of the early release. Trials were conducted over 7½ days, with a total of 200 participants for three different road user groups (cyclists, car drivers and motorcyclists). The evidence from this trial supported the progression to on-street trialling of LLCS with an early release. The evidence suggested that the system would be quickly understood by nearly all road users, would not adversely affect safety and could offer a benefit to cyclists in getting up to speed, clearing the junction ahead of motorists and feeling safer. The only caveats were that a small proportion of cyclists thought they had right of way when turning right across oncoming traffic and some motorists started moving before the main signals changed to red and amber.

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