Saturday, 28 February 2015

Tricky Tactiles

It's been an interesting and varied week for me (that's why I like being an engineer), but I am posting about one thing on my mind; the tricky subject of tactile paving.

Blister tactile paving - this one at a zebra crossing.
Tactile paving is ubiquitous on our streets, although those of us in the game and some users are the only people who know what it is for. I was at a workshop with Urban Design London earlier this week where we spent the day talking about tactile paving (living the dream!). 

We were fortunate to have Dr Kit Mitchell with us who was involved in the original research into using tactile paving when at the Transport Research Laboratory - specifically blister paving which is the square grid pattern of "bumps". It was proposed as a way of dealing with the important issue of providing flush kerbs at pedestrian crossing points. Of course, with flush crossings comes a significant safety risk for visually impaired people and so something was needed to show that people were at the edge of the footway. The blister paving was born. It is not a panacea as the blisters can be painful or uncomfortable for some people to walk on - the I'DGO information sheet on the subject is well worth a read.

Theory and practice are often different.
These days we have managed to land ourselves with 7 types of tactile surface/ paving which are often used incorrectly and potentially dangerously! "Guidance on the use of tactile paving surfaces" is the current design guidance which has been in place since 1998 and I would recommend that it is read and digested by designers and campaigners alike as it gives far more detail than I will here. 

The guidance is not without its problems as the layouts tend to be "perfect world" with "real world" examples of how one should cut tactile paving flags properly to fit curves. Maintenance is mentioned, but there is no practical information on how tactile paving should be laid - this would be good for designers, installers and maintainers (more on that later).

There is no legal duty to provide tactile paving, but given the need to ensure our streets are accessible to all as implied by the Equality Act 2010, it should definitely be used where visually impaired people are likely to be walking towards dropped and other flush kerbs at a road edge. There are other layouts in the guidance each giving a slightly different message and certainly, some uses are also of real benefit in terms of the safety of visually impaired people.

I have mentioned the square-grid blister paving which is used wherever people might be crossing the street and the kerb is flush with the road - it could be at a dropped kerb (ramp) or where the road (or a cycle track) is brought up to footway level. Blister paving should always be provided in pairs as we are sending the message to people with reduced or no vision that they are about to enter a road. For zebra crossings and signalised crossings, red blister paving is normally used and normally in an 'L' shape as in the first photo to indicate the push button being on the right for a signalised crossing. The "stem" which runs away from the crossing at right angles is to assist people in locating the crossing position. At other crossings (uncontrolled), a colour contrasting with the surround paving (other than red) is recommended, although people often use buff or light grey. 

Corduroy paving used at steps by the Cutty Sark in
Greenwich, London. The row in the foreground is at the
top of the steps, but there is none at the bottom which
leads into the road. In the distance, there is corduroy top
and bottom. In this layout, there should be two rows
(800mm) as people can miss them when stepping over.
Next we have the "corduroy hazard warning surface" which is a series of "bars" with round tops. It is intended to mean "proceed with caution" and is best used at the top and bottom of steps, but is also used at the bottom of a ramp leading up to on on-street "light rapid transit system" (trams etc), to warn that people are about to walk onto a railway platform, at railway level crossings and where a footpath joins a shared-use (unsegregated) cycle track. You can see why blister paving would be dangerous here!

Off-street platform edge at Cannonbury Overground
station. It is the single line of buff paving.
We then have platform edge (off street) blister paving (to be complicated) which is used to warn of the platform edge at railway stations. The blisters are offset in each row to form a triangular grid (rather then the square grid used for crossings). Only laid in a single line, this paving is used a white platform edge line and often a yellow line back from the edge. There is less risk of people stepping over this type of paving (so 800mm not needed) as people in a station will be taking care to find the edge.

From inside the tram, we can see the row of lozenge-
shaped bumps for the LRT tactile surface.
Following the rail theme, we next have a similar approach for railway stations, but this time we have "lozenge" shapes for on street LRT stops (trams etc). It is different from the off street blister paving because these stops are on the street and the railway blister could confuse people into thinking they are about to cross a road. However, as with railway stations, visually impaired people will be there by choice and so one row is needed.

Old Shoreham Road, Hove. Ladder is to the left for the
pedestrian side and tram to the right for cycling. A bit
confused here as people are entering a bus stop area

which is nominally going to be shared.
The 5th type of tactile paving has a series of flat-topped "bars" on them (similar to corduroy) and is used on shared-use, segregated cycle tracks. When the bars are laid across the line of travel (known as "ladder"), this shows the "side" for pedestrians, giving a rumble to people cycling over them. When laid with the direction of travel (known as "tram", this indicates the cycling "side", although the bars can catch bicycle tyres, worse when they are wet. The paving is used at the start and end of these segregated tracks and as repeaters.

A raised delineator strip on CS3 at Beckton.
The ladder and tram paving is used with the 6th type of tactile paving - the raised "delineator strip". It is essentially a small kerb or even a raised road marking (to the same dimensions) used to help visually impaired people to keep to the pedestrian "side". Of course with protected cycle tracks (stepped, or kerb-separated) the ladder/ tram and delineator are not needed at all!

Guidance path surface - from the
guidance!
We finally have the "guidance path surface". Used in the line of travel, this paving type is easily confused with tram and indeed corduroy; but the shape is slightly different. It is intended to help visually impaired people navigate open spaces where building lines or kerb lines are not available by either following the paving or for cane users, using the ridges to follow with their canes. It doesn't often get used, but could be useful to guide people at public transport interchanges for example.

I have briefly set out the "official" advice on using the different types of tactile paving, and clearly, there is lots of room for confusion. As I mentioned at the start that I was at a workshop and it was to discuss in general terms what people thought was good and bad about tactile paving. Having engineers, urban designers and visually impaired people (plus some groups representing them such as Guide Dogs) was a great idea as I think everyone learnt a bit that day. 

There was some discussion on "non-standard" use of tactile paving for level surface (shared space schemes) which mark a nominal edge of footway to assist visually impaired people. For example, Exhibition Road in London uses corduroy paving. Of course, being a shared space scheme, one questions the need to demarcate anything as all users are meant to be sharing, right?

I will be blogging about shared space in the future and so in the case of Exhibition Road, I will simply state that groups such as Guide Dogs were extremely concerned about the concept (and remain concerned more generally), although the Royal Borough of Kingston & Chelsea belatedly engaged with those with concerns and did some testing. Personally, I am not convinced.

Oxford Circus, London. Note the tactile paving cut to
follow the curve of the kerb.
There was also discussion about some proposed changes to the guidance which the Department for Transport will consult formally on soon. This included the following points;

  • Flexibility to allow the back of a row of blister tactile paving to follow the curve of the dropped kerb (for crossings), rather than being straight, although the paving would need to be 800mm deep to make sure visually impaired people don't step over it.
  • Replacement of the requirement for blister paving at a controlled crossings (zebras, signalised) to be red, with a requirement for at least a 50% contrast ratio with the surrounding paving
  • Introduce a requirement for the boundary between carriageway and footway to be demarcated with tactile paving wherever they are at the same level

The first point in theory reduces the amount of paving area needed and in terms of how a street looks, follows the less is more idea without impacting on visually impaired people. I suppose this is fine if the paving is well-detailed and installed, but it will introduce more cut pieces of paving which are notorious for failing - a view expressed by quite a few people.

The second point is driven by aesthetics to some extent, although red tactile paving surrounded by red paving doesn't give contrast. Many people (including users) felt that contrast and the 'L' shape (when it should be used) was more important than the colour; frankly, if users are happy, then so am I.

The third point would cover any flush kerb situation. I suspect it was primarily driven by shared space schemes not providing some kind of demarcation between the "footway" and "carriageway" (which is oxymoronic), but would apply to speed tables and dropped kerbs more generally. I sometimes see speed tables which are poorly designed or installed which are flush, but with only a small area covered by blister paving (not necessarily on the desire line). Shared space issues to one side, this is a good idea.

An Israeli push button - note the arrow on the top
showing the direction of travel.
There was also a discussion on a suggestion to add a tactile arrow to the push button boxes to show the crossing direction with an example from Israel being given. Finally, there was a suggestion to provide a rotating tactile cone on push button boxes when used on both sides of signalised crossings (convention is only to provide on the right hand side). Although users are using the 'L' shape to find the push button, on wide crossings, if people found the push button on the left, why not have a cone. Seems to make sense to me. These part of the discussion prompted concerns that too many staggered signalised crossing are difficult to navigate by visually impaired people and straight through crossings were preferred.

We then spent some time debating how tactile paving is used with cycling schemes. Many people felt that mixing people walking and cycling was not desirable and separated infrastructure was required which was a bit difficult to get away from when the discussion was about using tactile paving to deal with segregated and non-segregated shared-use cycle tracks. There was less consensus here and probably not worth going into detail about to be honest.

I will be looking out for the consultation by the DfT as I want to raise the need to provide some design guidance on detailing and construction to avoid some of the poorly built layouts which require constant maintenance. By this I mean giving practical drawings showing how to properly cut tactile paving units, how to avoid diagonal cuts (which get used when ramp gradients are not properly set up) and how to bed the paving units to stop them breaking up (lay on concrete or mortar on concrete, never sand). Happy paving!

Friday, 20 February 2015

Motorways, Metrolink & Manchester

OK, it's the modern equivalent of sitting through someone's holiday snaps, but a recent trip to Manchester had me thinking - much to the irritation of my family!

No, I cannot switch off and to be honest who wants to when it comes to how our infrastructure works (or doesn't). Or it might just be me that finds it all so interesting. We had a long weekend in Manchester to see people and to see some of the city where part of my family once lived. I am not going to give you the full account you'll be pleased to know, just some transport thoughts.

A spookily empty M1, north of the crash.
We took the car and it was an awful morning on the way out. With fatal crashes on both the M1 and M40, we switched to the 'A' roads and ended up going through the city of the roundabouts which is Milton Keynes before rejoining the M1 further north. The M1 crash involved a coach hitting a car stopped on the hard shoulder. As the coach driver was arrested, one does wonder if the driver was confused about whether or not the hard shoulder was in use as a running lane at the time under the "smart motorways" project. I have never been a fan of the concept, especially as in some locations, it is hard shoulder running and in others, all lane running with no hard shoulder - one could see the confusion.

I don't have to drive all that often, but for long journeys with all 5 of us, it is the only economic solution. Trains are crazily expensive and cannot compete with the £60 in fuel for the round trip (yes I know, insurance, tax, depreciation etc). There was the usual congestion around Birmingham, complete with the M6 set up to encourage use of the M6 toll (we didn't). We went round Manchester on the M60 to visit a friend just outside Rochdale and then we headed to our hotel near Manchester Airport and got hopelessly lost in the city.

Avoiding the left hook. Image from Google Streetview.
As we found our bearings, I recognised a little bit of cycling infrastructure at the junction of the Mancunian Way and Fairfield Street. The layout is on the eastbound (Fairfield Street) approach to the junction where people riding bikes can leave the main carriageway and go into a little protected pocket (known as a "jug handle" due to its shape) and then on their own green signal (parallel to a pedestrian crossing) cross a two lane left turn slip road to avoid left hook. Once across, people are deposited into their own little protected "ahead" pocket where they continue east along Fairfield Street.

The reason I (very geekily) recognised the layout is that it appears in a very old "Traffic Advisory Leaflet" - TAL8/89, the earliest available online (I am not sure if it was the first one ever though). From what I briefly saw, the layout is identical today as it was in 1989 (aside from new bollards). The advantage to the layout is clearly that left turning traffic can be avoided. The staging of the signals has the cycle green coming in automatically when left turning traffic is held. The disadvantages are that there is never a clear run through the junction and the turns are a little tight. Of course, the main issue is that this is a single item in a location which is completely hostile to mass cycling anyway and so will probably remain an interesting historic curiosity.

The junction of Sir Alex Ferguson Way and Trafford
Wharf Road. No signals here for people on foot or bike.
Anyway, that was the journey there. The next day, we took in the Trafford Centre and dropped Ranty Junior off for a trip around Old Trafford with his grandad. The rest of us walked from Old Trafford to Salford Quays which was quite pleasant (although I imagine match days get a bit busy). We walked along Sir Alex Ferguson Way and onto Trafford Wharf Road. The area is a business/ industrial park with wide roads to match. There were cycle tracks on both sides of the roads here, but they had breaks at every little access point and mixed with pedestrians at crossing points. 

At 1.6m wide, the footway on the left is a bit narrow as is
the cycle track on the right at 1.9m. With the carriageway
as wide as this, it could have been very good.
The footways and cycle tracks were paved in contrasting materials and were in fair condition, but they were let down by poor dropped kerbs (often not flush) and there were signs of tree root damage. It was a Sunday lunchtime and we didn't see many people, so I can't say what it was like during the week. The layout could be tweaked (through maintenance) to give a stepped cycle track and to improve crossings - it could be really good.

On our third day, we wanted to leave the car at the hotel and get into the city centre by tram. Other than a ride on a tram in a living museum, none of us had actually been on a tram proper and we had the perfect chance. The first problem was getting to the tram stop closest to our hotel which was at Manchester Airport Station - about two miles away. This was not a journey we could make on foot with children (one in a baby sling) and we didn't really want to pay for a cab. Luckily there was a bus and even more lucky we got picked up close to the hotel (although even luckier than that, frequent was not a word to describe the service!).

A tram. Nice.
We bought a combined bus/ tram ticket on the bus using cash (remember that London?) and as we arrived at the airport bus stand, the driver told us which stop we should use for the return journey - yes, Arriva's chap was excellent. 

We then found our way to the Metrolink station (or is that stop) and hopped aboard a modern tram at a brand new station which only opened at the end of last year.

The signal to the left of the green means that a tram
may proceed ahead. 
As we headed towards the city we went through back land areas (some of which were old, long closed railways) and along streets, the tram did its job. On-street, traffic signals were set up to detect oncoming trams to give priority accordingly and progress was as you would expect from good public transport.

Cycle parking at a tram stop.
I did note that bicycles were not permitted on the trams, not even folders, although parking hoops and secure lockers (for a fee I assume) were provided by tram stops. We found the trams crowded in the evening peak (it was a Monday after all) and so full-sized bikes would be a pain for other passengers, but I would have thought that folders could be accommodated and full-sized off peak as with the Docklands Light Railway and some of the Underground in London.

Informal shared crossing of the tram line.
One other thing I noticed on the newer sections we travelled on was the amount of shared-use cycle tracks and Toucan crossings which had been built along the line.

On the sections between residential cores, they probably worked fine because of the lack of pedestrians, but in the busier areas, there wasn't enough space provided. A great deal of money has been spent on building this network and on the airport section, relief roads have also been built and so sadly, cycling has been given its usual bolt on which doesn't suit walking or riding a bike. There are also on-road sections where cyclists are advised to run between parked cars and the trams - certainly not for mass cycling.

As a service, we found the Metrolink system to be wonderful, even to the point where a I tweeted a smashed window on our tram which got an almost instant reply with staff on scene very quickly. We swapped lines a few times and rode up and down which is great entertainment for the kids and gave the adults a rest from walking round the shops. We also went back to Salford Quays on the tram and it was rather reminiscent of the experience in London's Docklands. We eventually went back to the airport and our bus was a 5 minute wait. This was also lucky as the next bus wasn't for another hour!

Friday, 13 February 2015

Carry On At Your Convenience

Why is it that some people put their own convenience above others? I am sick of seeing people parking on the footway because they are too lazy or ignorant to think about those who need to get past.

Whether it is someone popping into a shop and will only be a couple of minutes, a parcel company driver deciding that the footway is fair game, or a tradesperson trying to get their van as close as possible to the front door of the property they are working on, our streets are plagued by these people. 

Stop being so bloody selfish and park properly and yes, you might need to plan your journey better, park round the corner or do the job at a different time of day. Fools.

Why can't you deliver at a quieter time of day, or
use the rear entrance?

Are you happy with that bit of parking?

Park round the corner and walk round you lazy sod.

Saturday, 7 February 2015

Why Did The Zebra Cross The Road?

I like zebra crossings. They allow pedestrians to immediately gain priority of traffic and are far more flexible than traffic signals. This post is about where we are now and where I think we should be going with this British Institution.

The World's most famous zebra crossing at Abbey Road,
St. John's Wood, London. It is poorly lit, has no tactile paving and

the dropped kerbs are not great. But, it has its own webcam!
This idea has been hanging around for so long in my head that things are changing in zebra crossing design, but I will come back to that briefly later. 

The inspiration came from the humble Belisha beacon which celebrated its 80th Birthday last year - have a read of Wikipedia for more background. They are named after Leslie Hore-Belisha, the transport minister who introduced them at crossing points marked with metal road studs. 

Zebra crossings as we would recognise them didn't appear until 1951 when stripes were added to make the more conspicuous. For a detailed history, check out the brilliant CBRD website and we are indebted to Living Streets (previously known as the Pedestrian Association) getting them introduced in the first place. One important point to make about Zebra crossings is to get priority over traffic, people are actually meant to step onto them (easier said than done!).

So, let's kick off with the law. As usual, we have primary (acts) and secondary (regulations) legislation governing what we can do and Zebra crossings are no exception. S23 of the Road Traffic Regulation Act gives traffic authorities the power to establish pedestrian crossings on their roads (S24 gives similar powers to the Secretary of State for his roads - i.e. trunk roads). S25 of the Act gives power of the Secretary of State to make Regulations governing pedestrian crossings. We have to publish proposals and people have the right to object to them being placed.

The regulations which cover pedestrian crossings are the snappily titled "Zebra, Pelican & Puffin Pedestrian Crossing Regulations and General Directions 1997". (Northern Ireland has 2006 Regulations). For those worrying about Toucan crossings, don't they are essentially modified Pelicans or Puffins (same applies for Pegasus crossings for equestrians). Anyway, this is about Zebras.


A zebra crossing with an island and a central Belisha beacon
is taken as two separate crossings.
Other relevant law will be the Traffic Signs Regulations and General Directions 2002 (as amended) which covers the traffic signs and road markings associated with Zebra crossings. Later this year the ZPPPCRGD1997 (!) will be absorbed into the TSRGD (2015) which makes a bit of sense in my view (and I will post about it then).

In terms of "official" guidance, there are two things which can be referred to;

A word of warning. Although these are current Government guidance documents, they are almost 20 years old and so not a reflection of modern thinking, although the assessment document does try and get designers to consider sites on their merit and approach schemes logically. The design document goes into more detail on the general design and layout considerations for pedestrian crossings with specific advice for Zebra crossings.

At this point I need to remind you that guidance is not law and one is free to depart from it, so long as the legal provisions are met. In short, this gives rise to quite a lot of flexibility in how Zebra crossings can be laid out - far more than some of my peers would have you believe. For practitioners, it is good practice to keep a design note on the whys and wherefores, especially if you are going a little unconventional.


The humble Belisha beacon
So, what constitutes a Zebra crossing? First, it is the Belisha beacon. The size and colour of the flashing globe is regulated (along with the flash rate). The beacon mounting height is regulated and so are the black and white stripes on the poles.

Then we have road markings. We of course need the black and white stripes on the road (the black normally being the road surface) which have their dimensions regulated along with the layout, number and length of the zig-zags (known as the "controlled area"). We also have stop lines and crossing studs (painted or metal) to think about. Schedule 1 of the ZPPPCR1997 gives the ranges.

One other thing to consider is the often thorny issue of tactile paving. Now, it is not specifically a legal requirement, but with the provisions of the Equality Act 2010, highway authorities need to ensure that new schemes are accessible and this includes substantial maintenance work. 


Your basic zebra crossing tactile paving is red, with a row of two
tiles at the dropped kerb and a "stem" 3 tiles wide which ideally
runs to the back of footway to blind and partially-sighted people
can find and orientate themselves.
Tactile paving is there to guide people with visual impairment to the crossing point and is needed because of the need to provide flush crossing points for the benefit of people with reduced mobility. Guidance on the Use Of Tactile Paving Surfaces suggests that the tactile paving should be red to denote a controlled crossing (i.e. pedestrians control traffic by stepping onto the crossing).


Even though red is the recommended colour, the guidance also refers to the need for a colour contrast. It is more relaxed in conservation areas as some urban designers and others don't like tactile paving full stop and red brings them out in a rash. I also have it on good authority that this guidance is being revised, but there is nothing out for consultation as yet. The guidance also refers to trials of an embossed "Z" on the post to assist blind and partially-sighted people distinguish from a signalised crossing, although I have never seen this "live" myself.

The tactile paving should be 'L' shaped. As one stands by the crossing, the 'L' will be upside down with the 'stem' on the right hand side along with the beacon. The arrangement is to hint at people which way the traffic will be coming from as they start to cross and for a two-way road the "L" shapes won't be a mirror image across the centre of the road (it remains the same on a one-way street). Where Zebra crossings go to islands, the recommended arrangement of tactile paving is given too.


A zebra crossing may be put on a road hump (flat topped!), but
other humps are not allowed within the controlled area (zig-zags).

In this photo, we also have the beacon globes mounted around
the posts, light-up stripes on the posts and the post has high
level lighting.
We are also allowed to put the zebra crossing on a road hump (flat topped speed table) which can help slow traffic and make the crossing flatter for users and we can put refuges in the middle of a crossing making, sometimes making it a two-stage non-staggered crossing (and you can stagger them if you really must, but this is relatively unusual). We are also able to light crossings, have the white stripes on the beacon posts light up (not flashing) and mount kit in all manner of creative ways.

So having read all of the above, my suggestion is bear the fact in mind that there are some things we have to do when designing zebra crossings, but they are very flexible so we can start with the basics. Pedestrians want to cross on the desire line and that should be our starting point. All too often zebra (and other) crossing are placed where people won't use them and are then funnelled with miles of guardrail to force them to be used.


This image (from Google Streetview) is a classic example of a zebra crossing where the guardrail probably cost more than the crossing itself. I say probably, because I cannot remember - this was the first zebra crossing I built*, but in my defence I didn't design it, I worked for the maintenance team at the time and we installed schemes for the traffic team. (*yes, 'I' didn't physically do the work, but you know what I mean!).

This crossing, on Link Road, Canvey Island, Essex, was installed around 1996 and (from memory) it was to help school children cross this busy road. There must be well over 100 metres of guardrail to keep the kids penned in, although once they are beyond the guardrail goodness only knows what they would do.

Many years after this crossing I am still involved in their design, but fortunately, I think I know what I am doing now (well, let the users be the judge of that I suppose). On guardrail, I am at the opposite end of the spectrum these days and I would generally not design it into a scheme. One exception for Zebra crossings would be where they are closely associated with a school pedestrian entrance as there are often crowds of people milling about who could knock a smaller pedestrian into the road. In this situation, I would offset the crossing from the gate by a few metres so the guardrail protects people immediately at the gate.



When we look at desire lines more generally, crossing a side road can be an issue for people and although unusual, zebra crossings can be placed across the entry to the side road. The photo above is a panorama of the Abbey Road crossing (to the left) and its sibling across Grove End Road. LTN 2/95 recommends;


Another side road zebra at St. John's Wood High Street, note that
no zig-zags are present on the right hand side. The Regulations
require a minimum of 2 markings and so this crossing does not
strictly comply with the rules. The buff coloured tactile paving does

not confirm to guidance on colour. I wonder if the designer 
recorded the reasons for these issues?
Crossings on a minor road should not be sited very close to a ‘GIVE WAY’ or ‘STOP’ line. Generally the nearer the crossing is to the major road the greater will be the distance to be crossed. Drivers of vehicles turning into the minor road need time to judge the situation and space in which to stop.

So you can put them on a side road and being close to the junction might be better than tucking them away from a desire line and visibility point of view in any case. On the main road, LTN2/95 recommends;

Crossings should be located away from conflict points at uncontrolled junctions. This will give drivers an adequate opportunity to appreciate the existence of a crossing and to brake safely. The ‘safe’ distance will depend on the geometry of the junction and type of side road. However, a minimum distance of 20 metres is suggested for a signalled-controlled crossing and an absolute minimum of 5 metres for a Zebra crossing. It is suggested that the distance be measured from the position of a driver waiting at the give-way line of the side road. Where it is impossible to obtain a ‘safe’ distance, consider banning turning movements towards the crossing or make the side road one way away from the junction.


Silk Street in the City of London. Near a funny roundabouty thing,
but seems to work OK. The bright band of lights around the
Belisha beacon globe are by Zebrite and are really bright even
during the day.
Many zebra crossings are well away from junctions, but where put near one, putting too far away can mean that again, people might not use it. For me, visibility and traffic speed are the issues and if the latter is too high, we can put the crossing on a hump or reduce traffic speeds other ways. A crossing in the wrong place is at best a waste of money and at worse could lead to drivers who expect people to cross on a zebra crossing missing someone crossing a little further away (and that is not excusing a lack of driver attention).

Zebra crossings can be placed near roundabouts (both kerbed and mini) although they should be kept away from any flares out to multiple lanes as there is more to cross and multiple lanes are risky (more on that later). I would set a crossing back from the give way line of the roundabout to allow vehicles to leave the roundabout circulation area, although in tight situations with mini-roundabouts, it might not be possible.


A test layout at the Transport Research Laboratory with added
cycle lanes/ tracks.
With larger layouts, it might be worth leaving space for a couple of vehicles and the greater the gap, the better the visibility between pedestrian and driver as the crossing is square with the direction of the road. Of course there is a balance to be had with pedestrian desire lines here.

Zebra crossings should be a minimum of 2.4m wide, but can be up to 5m wide where pedestrian use is high and with approval (by the Secretary of State) up to 10.1m in width. They should be square across the road where possible and zig-zags are normally 8 markings (with the configurations prescribed). This can be reduced to 2 markings or increased to 18 (and markings reduced to 1m in length) and zig-zags apply the "controlled area" rules within them. The variation in length and number of zig-zags is often used to start or end them one side or another at a side road foe example. Paragraph 10 of Schedule I of the Regulations state;



Given that that at least 2 markings are required, the St. John's Wood High Street example in the photo above is technically unlawful. It is sometimes argued that a Zebra crossing in the spirit of the rules is fine which would "clear" the St. John's Wood High Street example, except S10 of the Regulations state;



To omit zig-zags completely (i.e. the controlled area) is pushing it a bit, although there is an argument that the layout of the St. John's Wood High Street is clear enough and there are loads of examples of this layout. I would be inclined to leave that to the courts! There are more niceties of the rules, but I shan't bore you any more.


The visibility of a Zebra crossing is important in terms of drivers being able to see pedestrians and pedestrians being able to see vehicles. LTN2/95 suggests that with a speed of 30mph, the forward visibility for a driver should be 65m (absolute minimum 50m) and at 40mph, 100m, (absolute minimum, 80m). These are measured 85th percentile speeds rather than the speed limit given how some people choose to drive. 

The visibility is a guide, but if the measured speeds are 35mph and above, design with caution and if they have reached 40mph, then a Zebra crossing is not appropriate in my view and speeds need to be reduced, or a signal-controlled crossing provided which can adapt to higher speeds. When designing, I would also want to make sure that drivers can see people approaching a crossing or waiting to cross and so as a rule of thumb, I want to have a clear view to the rear of the footway, or at least 2m back from the kerb on a wider footway.



Warning signs may be provided in certain cirumstances, although to be honest, we use too many. The sign on the left is the UK sign for Zebra crossing ahead, while the sign on the right is a Danish version (with many around the world looking similar). I think the sign on the right makes more sense, but it means something different as outside the UK, many mix stripes with traffic signals.


A pretty basic spotlight and pretty crappy it is too.
Lighting of Zebra crossings is important and is covered in LTN2/95. Practically, people waiting to cross and actually crossing need to be seen by people driving when it is dark. If the street lighting is very good, then no additional lighting is needed - the example above of Silk Street has no additional lighting (although I haven't seen it at night) and often city centres will be fine, although glare could be an issue in affecting the vision of people driving.

Away from the bright lights of the city, or if a higher level is needed to compete, then specific lighting is required. It is often the case that the Belisha beacon has a spotlight attached to do this extra job. Frankly, they are awful and should no longer be used. They might illuminate the waiting area, but rarely do a good job of lighting the crossing.


The Zebra lighting is on top of a 5m lighting
column. Most street lighting manufacturers have
their own "zebra" versions of common luminaires
The modern approach is to use lighting which illuminates the vertical of people waiting and crossing, rather than the plan which normal street lighting provides. Using clever optics (known as "linear beam spreaders" - thanks Jono Kenyon!), modern Zebra lighting is great. To keep clutter down, the Belisha beacon can be mounted on an ordinary lighting column which is then given the Zebra paint job.

There are many ways the Belisha beacon globes can be mounted. Given that I have endorsed high level lighting, you are faced with two options; first, they can be mounted on brackets and second (and rather funkily) the globe can wrap around the post.

The product I have used for years is the Midubel, by Simmon Signs. I have nothing personal to declare with the company, I have just found their products to be excellent in the years I have known them, plus their customer service is second to none (they will even teach your street lighting contractor how to fix the kit). You don't have to centre-mount the beacon, but it just looks tidy.


This Zebra crossing has illuminated posts
helping to show the crossing against a
backdrop of vehicle headlights and shop fronts

High level lighting in action (with vertical optics) nicely lighting this
Zebra crossing, complete with centre-mounted Midubel globes.
As mentioned above, I am not a fan of multi-lane Zebra crossings. Apart from the width that people have to cross, if traffic is busy, then one slow moving lane can mask people stepping out into a lane with faster moving traffic. I realise that people approaching the crossing should be aware of this and slow down to anticipate pedestrians, but they don't and so I think multi-lane approaches are inherently dangerous. Even with free flow of traffic, the first driver might stop, but if the second one doesn't, you've had it.

This does bring me onto the tricky issue of pedestrian refuges placed within a Zebra crossing. These are used for two reasons. First, so that people can cross in two halves. As with multi-lane approaches, a slow moving lane in one direction can mask people crossing and a refuge deals with that problem. Second, on busier roads, a refuge can be less of a hold up to drivers which means a pretty flexible layout can be provided.


Just awful. 3 lane approach one side, 2 wide lane approach on
the other, a narrow stagger and kerbs which are not flush. This is
Winston Way, Ilford, East London. From Google Streetview.

A multi-lane Zebra crossing, Victoria Embankment, London.
The problem is that pedestrian refuges need to be at least 1.8m wide in order to be accessible for all users (otherwise there is not enough space for a mobility scooter user or people with buggies) and the refuge island can create pinch points for those riding bikes on the carriageway.

You can squeeze the carriageway down to about 3 metres which means that people riding bicycles cannot be overtaken (but those cycling become a rolling road block), although some drivers try, or you can have the carriageway at 4.5m to allow overtaking, but it feels close when you are on the bike. The answer is that in conditions where people need help to cross the road, it is likely that people cycling need protection from traffic. 


Cycle Superhighway 3, Cable Street, London
There is no cheap answer here; something which helps walking can make things hard for cycling. On the flip-side, when we accommodate cycling, we can make life more difficult for pedestrians. Cable Street in London carries Cycle Superhighway 3. It is a bidirectional cycle track running next to a one way street. It is narrow in places, but a pretty decent bit of cycle route. 

The problem is that the zebra crossings make life more complicated for pedestrians who have to content with traffic and two-way bikes; every time I use the route, there are often people riding through, heedless of people trying to cross. Yes, driver compliance at crossings can be poor too and we are dealing with bad behaviour by people, rather than by the mode they are using. It is a compromise as there is often not enough space to provide a decent refuge.


In Bristol, they are trying something a little different on Baldwin Street, using stripes of block paving to hint at pedestrian priority over a new bidirectional cycle track. Thanks to Maidstone on a Bike for the photo - there is more on his blog. This is not a zebra crossing and personally, I do have some concerns about the outcomes if either a person riding or a person walking assume they have priority at the wrong moment.

The "hinted" crossing is an attempt to give priority to pedestrians. Given that this is next to a Puffin crossing, it is reasonable (in my view) for pedestrians to think they have priority over the cycle track. I do wonder what people with visual impairment would do here as the tactile paving "stem" extending to the rear of the footway is there to guide them to the push button on the crossing.


The layout has come from the frustration that we don't have a cut-down version of the zebra crossing just for cycle tracks. We can build a full-sized zebra crossing such as this one under test at the Transport Research Laboratory, but they are messy.

In this case, we end up with the full complement of tactile paving and beacon posts creating physical and visual clutter. We need to just be able to put the black and white stripes down as they do elsewhere in the world as is well discussed by Mark Treasure of the As Easy As Riding A Bike blog. Zig-zags are not needed as people won't be parking bikes on the approaches to block views. I am still a little concerned about the impact on people with visual impairment and so we will need tactile paving as guidance. To be honest, this is an area beyond my expertise and there definitely needs to be more work and discussion with users on the subject - it is just we have never really done it and we are all learning.


This is pretty good, all of the basic components and with a speed
table to slow vehicles and give a level walking surface.
Zebra crossings are not just confined to the highway, they are ubiquitous in cars parks everywhere, marking a "safe" route for pedestrians. Quality varies and of course, they are not subject to highway law, although get it wrong and people can be killed.

I have designed a couple in my time and I think as long as the stripes and the Belisha beacons are there, along with tactile paving and a flush kerb you are there. In a car park, zig-zags are not really needed and I would hope speed and visibility are not issues - as ever, good basic design principles apply.


The problem I find with these "private" Zebra crossings is that they are often poorly laid out and poorly detailed with the usual being a lack of flush kerbs at the crossing point. As with highway authorities, operators of retail parks are required to make reasonable adjustments to assist all customers in line with the Equalities Act 2010 and in a new build, there is no excuse for duff work. Of course, retail parks are there to attract people by car and pedestrians are often an afterthought, even though the car-borne customers complete their journey through the car park by foot!

We are currently waiting for the Traffic Signs & General Directions 2015 to be enacted. One of the proposals in last year's consultation, was to create a "cycle Zebra" which is essentially the creation of a parallel cycling crossing next to the stripes of the Zebra which is reserved for pedestrians.



Partly because this is a post about Zebra crossings for pedestrians and partly because this layout is new (there has been a couple of schemes with similar layouts) I am not going to spend time on it - a subject for another day.

Yes, I like Zebra crossings because of their flexibility. If by a railway station, hoards of people in the morning and evening can get priority over traffic where a signalised crossing would hold people up on busy footways waiting for a green man (or they will just ignore it). At the same kind of location, during the quieter times of the day, there are no traffic delays, but people can just turn up and cross. Their design and location need a lot of thought and when being built, attention to detail is everything.

Wednesday, 28 January 2015

Under Siege

Imagine for a minute, that you run your own business as a sole trader. Imagine that your chosen business is under threat by "the powers that be" because the conditions under which you operate are being changed. Imagine also, that the specialist equipment you have spent a small fortune on is obsolete and your regulator will be changing the rules so you have to invest in a new set of equipment.

If I were a cabbie in London, I would be a bit worried and possibly quite annoyed at the moment. The Mayor of London has decided to press ahead with the North-South and East-West cycle superhighways and diesel engines which power the taxis are helping to ruin our health and so controls may well be on their way. Not only that, there is competition to contend with and so perhaps we might forgive them for being prickly.

I have been inside a black cab twice. Once as a punter years ago and once "on the job" going round with the local LTDA rep to look at what improvements could be made to some taxi ranks. My other experiences with black cabs have been when riding my bicycle or walking. This has varied from the drivers being utter tools by not giving me room when overtaking or bullying when I'm crossing the road to being the absolute height of courtesy. Do you know what, yes, they are people too!

In the last day or so, we have had rumblings from the LTDA (Licenced Taxi Drivers Association) that they might be seeking a judicial review on the Mayor's decision on the cycle superhighways. Unsurprisingly, the LTDA don't have much sympathy from many people who cycle in the Capital. Their Chairman, John Thomas, went into a demented rant back in March last year with this gem spotted by Cyclists in the City - have a read, it really is entertaining. My favourite bit (naturally) is this;


"the ‘experts’ in traffic, who are so cycling centric that they are blind to the consequences of their actions. Or is it that they just don’t care?" 


Really? I think 'experts' in traffic have been anything but cycle-centric for decades which is why our urban areas are just hell-ridden traffic sewers. I am pleased to report that bit by bit, my profession has woken up from its slumber and is rubbing its eyes. 

The LTDA has form of course, in this 'expert', 'scientific' observation, they were able to conclude that 53% of cyclists ignore red lights or that 'marshal law' was imposed in London for "Ride London" in 2013. Yes LTDA, we get it, you don't like cycling or people who ride bicycles and are happy to lump us in a group. Over on Twitter, I did my own little bit of gentle baiting, including calling for a boycott of black cabs. Actually, I was being daft, I don't use them. Perhaps some of the big businesses who supported the superhighways might rethink their custom?

In the final analysis, I don't really have an axe to grid against the cab trade as a whole; after all, I am the first to moan about being lumped into this group called "cyclists" (see above). I think the LTDA are being stupid and if I were a member, I would be questioning their motives. Cab drivers don't have anything to fear from providing for cycling and they are attacking the wrong targets. They should be questioning why we allow unrestricted (Congestion Charge acknowledged) use of private vehicles in the centre of our City taking up valuable capacity.

Taxis provide a service to people who are willing to pay for it (and it is not cheap) and for people who rely on them for their mobility as they are unable to use buses or other modes. This does not have to change and I cannot see people switching from black cabs to bikes. But, things are starting to change and those who cannot adapt will ultimately slide the way of the dinosaurs, possibly into a diesel-chocked tar pit.