Let’s Have a Mass Debate

Now that I have your attention, let’s talk 50 shades of grey. Ok let’s talk about another grey area in temporary traffic management. In particular, can I install a three or four way with a 12D M2 qualification? Now, straight away your all saying don’t be daft, but I will explain.

7 The 12D M5 qualification is to install a multi-phase traffic signal set up. That’s where a three way has three individual phases. Now what if the same three way only has two phases? Getting my drift.
We all know that on a three way we use the sign opposite, which clearly states 3-way control and doesn’t even mention phases. So can I install a three way control which only has two phases? The main carriageway is phase one and the side road phase two, only two phases so if I change the 3-way control sign to a WHEN RED LIGHT SHOWS WAIT HERE , that’s a two phase set up which I can install with a 12D M2 card.

uj In chapter 8 diagram SC12 clearly shows a four way set up using the 7011, WHEN RED LIGHT SHOWS WAIT HERE. Is that because it only has two phases?
So let’s go back to the three way which only has two phases isn’t that the same as using the adjoining traffic not under signal control but using a traffic signal. Again two phases with 3 approaches, which can be installed by a M2 operative. So I asked myself what is the difference between three approaches with two phases and three way control with two phases? Surely if I can install one with a M2 card why can’t I install the other with a M2 card?
The 12D M5 course is for Multi-Phase, Portable Traffic Signal Installations;
Definition:
Temporary Traffic Management Systems incorporating the use of portable, temporary traffic signals to control 3 or more phases

So Can I install a three way with two phases on my M2 qualification?
Please don’t start installing a 3 way unless you hold the M5 card.
I’m not even going to talk about, do I need an IPV on a 30mph dual-carriageway.

3 Comments

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3 responses to “Let’s Have a Mass Debate

  1. Steve Randall

    The Red Book (Oct 2013) suggests that any form of traffic signals controlling more than 2 directions would be a multi-phase set up, the key to this is shown below regarding the shuttle lane, so on this basis if, for instance you have a side road coming on to a main road and you wish to reduce the witch of the side road at the bell mouth then the shuttle lane would only be on the side road, therefore phase 1 would be the main road running in both directions simultaneously whilst the side road would operate as phase 2 (as a shuttle lane) the diagram you show with the 4 way set up has a shuttle lane on both carriageways therefore this would be a multi phase set up

    (Excerpt from the Red Book)
    Three-way and four-way traffic control (multi-phase)

    Three-way or four-way control may be appropriate where a side road junction is within the shuttle length.

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  2. kev terry

    gary I would say yes, if its only using two phases then M2 qualification should apply, but then again there are many people out there don’t even hold that cert!! and still band jobs out

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