No, not the old “illumination of traffic signs” item that was never published and can now be covered neatly in TSRGD itself. This is the re-purposed Chapter 6 that will revolutionise the use of traffic signals in urban areas now that the over-designed monstrosity that is the old DMRB TD 42/95 (now CD 123) has been stripped back to apply to major roads with speed limits in excess of 40 mph.
Chapter 6 forms the basis for all urban signal design as a result now. It has been much awaited and despite delays affecting the DfT it came out during the election period (we weren’t supposed to know but these things slip out). Now it’s formally out let’s review the best bits.
The first positive change is the shift in focus from ‘movement’ towards ‘place’. This means that urban areas are no longer to be seen as just ribbons of traffic dominating the streetscape and should be redesigned to allow better movement of pedestrians and cyclists, who on average are the economic drivers of urban areas. Others have written entire dissertations on this, all I’ll say is Google it. As part of this change, the DfT have abandoned previous efforts to suggest you need certain traffic flow parameters before you can do something – historically people would hide behind nebulous casualty criteria to justify not installing a pedestrian crossing, for example. Likewise the Deregulation Act 2015 has removed the requirement to notify the Secretary of State so several of these legal hurdles that were also used as obstructions by “do nothing” authorities are out of the way. The only hurdle now, typically, is money.
Traffic capacity is still obviously a concern, but the suggestion is now you should be looking at ways to relocate this traffic if at all possible rather than turning a small market town into a major traffic hub at the expense of everybody else. See, bypasses still have their place… in an ideal world through traffic would be eliminated and routed around the central core.
The late start signals, e.g. in Manchester where a right turn green arrow is used at the start of a wider green stage on that approach rather the end (early cut-off) is deprecated as unsafe. There are exceptions, such as the very effective ‘back to back green arrow’ as seen in Humberside where two right turns are permitted to clear the junction before the ahead movements are released. These have been imported to Blackburn in recent years and they work very well, I’d like to see more of them truth be told – Manchester definitely would benefit from these!
Another good thing is that the expectation of giant high speed radii has gone, with the acceptance vehicles will foul the opposite of the road if they are big and probably not meant to be there in the first place. Likewise there is finally acknowledgement that lane widths between 3.2 and 4m are a bad design feature if you have high volumes of cyclists.
Thankfully the general move towards decluttering is maintained; with specific reference to signal junctions having over-provision of signal heads. It is rare you need more than the primary and secondary, so why do junctions have as many as three or four signal heads per approach – this is often ridiculous and rightly called out by these guidelines.
Again to reduce clutter the emphasis is on the correct use of regulatory ‘box’ signs on signals where appropriate. Likewise, warning signs are not necessary if the signals are plainly visible. This is a particular bug bear of mine, as often the warning signs obscure the signals themselves! There is no legal requirement to place warning signs so unless it is absolutely necessary, don’t bother.
Additionally the dreaded temporary signs are under attack – again these are not needed. Locals know the signals are new, and outsiders won’t know any different. Don’t bother putting up the signs, they won’t come back down and they’ll clutter up the street.
Cycling & Pedestrians
The recent advances in signal design mean that cyclist facilities were rapidly being left behind by the guidance. Chapter 6 addresses this and details emerging designs such as ‘hold the left’, ‘right turn in two stages’, and the best of the new innovations, the low level cycle signal.
An excellent paragraph, and one I will quote verbatim:
Pedestrians are more likely to ignore the red signal if they consider the time they have to wait is unreasonable. While waiting at a junction in bad weather, a driver may be frustrated but is generally warm and dry. A frustrated, cold and wet pedestrian is more likely to take risks. A crossing that requires them to deviate off their desire line further than they consider acceptable is also unlikely to be used.
Non-motorised users need direct and reliable routes. It is the structural foundation of active travel design, and to ignore it in favour of motorist convenience is why we have such endemic congestion as people drive instead of walk or cycle short distances. But if you don’t subscribe to active travel anyway none of this is relevant and carry on as normal.
As an aside, notice all the cycle lane infrastructure is shown in green… but this is optional. Personally I’ve always liked green for cycle routes. I will write a separate blog post about further improvement to cycling signs and future proposals for the DfT to consider (or most likely reject out of hand because of the expense and difficulty in changing everything over now).
The other good thing is the old Pedestrian Crossing Regulations which stipulated what you could and could not do within a controlled crossing area have been simplified (they’re now in TSRGD) and this guidance fleshes it out. Diagrams showing how cycle lanes should continue through crossings and so on are finally included. It also says to stop using guard rails unless absolutely necessary as well, given they have no proven safety benefit and just encourage risk taking by pedestrians (see quote above).
The bulk of the guidance is technical and relates to signal configurations which are not really my remit, but the overall result is a leap forward and I suggest if you have not familiarised yourself with the fact it now exists you take time to do so!