Editing Traffic light (section)

==== Green arrows ====
Arrow aspects may be used to permit certain movements or convey other messages to road users. A green arrow may display to require drivers to turn in a particular direction only or to allow drivers to continue in a particular direction when the signal is red.<ref name=":1" />{{Rp|location=3.5}} Generally, a green phase is illuminated at the beginning of the green phase (a "leading turn") or at the end of the green phase (a "lagging turn").{{Citation needed|date=December 2021}} An 'indicative arrow' may be displayed alongside a green light. This indicates to drivers that oncoming traffic is stopped, such that they do not need to give way to that traffic when turning across it. As right-turning traffic (left-side drive) or left-turning traffic (right-side drive) does not normally have priority, this arrow is used to allow turning traffic to clear before the next phase begins.<ref name=":1" />{{Rp|location=3.5}}

Some variations of this setup exist. One version is a horizontal bar with five lights&nbsp;– the green and amber arrows are located between the standard green and amber lights. A vertical five-light bar holds the arrows underneath the standard green light. In this arrangement, the amber arrow is sometimes omitted, leaving only the green arrow below the steady green light, or possibly an [[LED]]-based device capable of showing both green and amber arrows within a single lamp housing.<ref>{{Cite web |title=MUTCD 11th Edition - Part 4 |url=https://mutcd.fhwa.dot.gov/pdfs/11th_Edition/part4.pdf |access-date=13 December 2024 |website=[[Federal Highway Administration]]}}</ref> 

A third type is known as a "doghouse" or "cluster head"&nbsp;– a vertical column with the two normal lights is on the right side of the signal, a vertical column with the two arrows is located on the left, and the normal red signal is in the middle above the two columns. Cluster signals in Australia and [[New Zealand]] use six signals, the sixth being a red arrow that can operate separately from the standard red light.{{Citation needed|date=December 2021}} 

In a fourth type, sometimes seen at intersections in [[Ontario]] and [[Quebec]], Canada, there is no dedicated left-turn lamp per se.<ref>{{cite web |title=RoadSense for Drivers&nbsp;– Signs, Signals and Road Markings |url=http://www.icbc.com/driver-licensing/Getting-licensed/drivers3.pdf |url-status=dead |archive-url=https://web.archive.org/web/20131022032056/http://www.icbc.com/driver-licensing/Getting-licensed/drivers3.pdf |archive-date=22 October 2013}} Accessed: 25 March 2014</ref><ref>{{Cite book |title=Ontario Traffic Manual Book 12: Traffic Signals. |publisher=Ministry of Transportation of Ontario |year=2012 |pages=55}}</ref> Instead, the normal green lamp flashes rapidly, indicating permission to go straight as well as make a left turn in front of opposing traffic, which is being held by a steady red lamp. This "advance green", or flashing green can be somewhat startling and confusing to drivers not familiar with this system. This can cause confusion amongst visitors to British Columbia, where a flashing green signal denotes a pedestrian-controlled crosswalk.<ref>{{Cite news |last=Tchir |first=Jason |date=June 23, 2015 |title=Why B.C.’s flashing green lights don’t mean the same thing as those in Ontario |url=https://www.theglobeandmail.com/globe-drive/culture/commuting/why-bcs-flashing-green-lights-dont-mean-the-same-thing-as-those-in-ontario/article25066266/ |url-status=live |archive-url=https://web.archive.org/web/20241214013728/https://www.theglobeandmail.com/globe-drive/culture/commuting/why-bcs-flashing-green-lights-dont-mean-the-same-thing-as-those-in-ontario/article25066266/ |archive-date=December 14, 2024 |access-date=April 21, 2025 |work=[[The Globe and Mail]]}}</ref> For this reason, Ontario is phasing out the use of flashing green signals and instead replacing them with arrows.<ref>{{cite web |title=RoadSense for Drivers&nbsp;– Signs, Signals and Road Markings |url=http://www.icbc.com/driver-licensing/Getting-licensed/drivers3.pdf |url-status=dead |archive-url=https://web.archive.org/web/20131022032056/http://www.icbc.com/driver-licensing/Getting-licensed/drivers3.pdf |archive-date=22 October 2013}} Accessed: 25 March 2014</ref><ref>{{Cite book |title=Ontario Traffic Manual Book 12: Traffic Signals. |publisher=Ministry of Transportation of Ontario |year=2012 |pages=55}}</ref>