As head of design for Transport for London (TfL), Jon Hunter (above) has responsibility for a large part of what the millions of residents of the UK's capital who use the network every day experience.

Jon's main role is managing how the TfL brand permeates out to cover myriad forms of design from wayfinding and information design to graphics whose purpose is purely aesthetic – as well as architecture, vehicles and fashion design.

I caught up with Jon after a talk at Adobe's recent Design Advantage Forum conference, where he articulately discussed some of TfL's recent design projects – including the redesign of staff uniforms by Wayne Hemingway – despite a chest infection.

TfL's brand principles

I wanted to find out more about how branding translates into fashion design, but first I wanted to get a broader handle on the core brand principles that underpin all of TfL's design projects. I began by asking Jon to describe how he sees how the TfL brand is perceived by its customers.

"One thing we do try to build on is that people have a relationship with their own version of TfL," says Jon, "whether it be the underground or the buses or the many other things we do. A lot of customers aren't aware of [all of] what we do. We manage the red route, thousands of sets of traffic lights, road maintenance, crossings.

"We enable walking and cycling, even though we don't make money from those – we provide them as a public service. A lot of customers who have a relationship with the Underground maybe don't realise that."

Having a consistent brand that can work across all of what TfL does requires a flexibility to adapt to all of those forms and functions, and clear delineation between them. Jon says that one of the most important distinctions that they have to make with TfL's various sub-brands is between modes of transport that TfL has complete responsibility for – and control over – and those it doesn't.

Here uses the example of one of TfL's best-known marks, the roundel (below, alongside Daniel Buren's artwork at Tottenham Court Road Underground station). People generally associate this most with the Underground network – which is what it was originally created for, as signage for what's now St James's Park Station and then spread from there – but it's used across TfL's ticketed transport network including buses, the Overground, DLR, trams and the River Services (as well as the London Transport Museum).

"We only give the lovely roundel shape to an operational mode that we generate revenue from," he says, "one we provide the [complete] service to the customer so we basically – something that they might need to pay for, or they might get subsidised, such as guide ride. Things such as walking or cycling – because we don't have complete control over that customer experience we would not provide a roundel, though we would make sure that we try and get as many of our brand principles into that."

There's also a clear delineation between information for the here and now and 'softer', less time-sensitive media. What a customer needs to know right now – which way to another line or the Tube map – has a clean, functional design with bold type in the New Johnston typeface.

Other media have more diverse, more aesthetically pleasing forms. This brings us onto one of my favourite recent design projects from TfL, Mcbess' posters that combine his hallmark characters with poetry hand-lettered type encouraging users to be safer, kinder and help the network run more efficiently.

"What we need to make sure is the campaign or the message has enough freedom," says Jon. "that it's not seen as 'oh it's another poster for another campaign'.

"People do say 'why aren't you using the New Jonson font, as it's the TfL typeface?' – and we say it's because we don't want that to look as if it's [purely informative]. We have to constantly do that otherwise a really important message might not get seen by a customer."

Watch TfL's video interview with Mcbess talking about creating illustrations for the 'kindness' campaign.

Designing for commuters and tourists

In a city of 8.6 million people, with 17.4 million tourists visiting every year, TfL's customers are a hugely broad range. At the extremes, you have the commuters who take the same route every day but demand to kept up to date about any impediments to that journey – and tourists who may not speak or read English well. And then there's everyone in between.

So I asked Jon how you can present information to customers in a way that's helpful to all of those customers – but deliver it in such a way that's efficient for commuters in a rush (hour). He says that TfL's approach is to provide the core information – whether that's when the next train is or which station or stop you're approaching – in the most obvious places, and then draw those who need more help into areas specifically designed for them (I'm guessing to get them out of the way of commuters too).

"We've just invested in revamping our travel information centre so they are now called visitor centres," says Jon. "They are quite brightly branded. We've retained the purple look that started at the Olympics, because that's who we are to a lot of overseas visitors.

"The centres are staffed with specialists who are able to give you advice. Primarily they're to give you information, but if you would need any tickets, they can sell you tickets."

These centres are primarily placed at what Jon calls "gateway stations", places where tourists are most likely to arrive. Each centre is designed for the types of people coming to each station, as the needs of a tourist from Glasgow arriving at Euston are different to those of someone coming from Paris or Brussels into St Pancras on the Eurostar.

A new uniform for TfL

One of the biggest projects that Jon is overseeing is the rollout of a new uniform for all TfL staff, which has been designed by Wayne Hemingway (above with TfL staff modelling the new uniform). Previously there was no consistency in the uniforms across the different parts of the TfL network – and research conducted by Jon's team discovered that most people didn't remember staff wore a uniform beyond occasionally seeing people in hi-vis jackets (though, as Jon notes, those could have been builders commuting).

So TfL wanted a uniform that was consistent – making it easier for customers to spot staff without being in-your-face like theme park employees – but with coloured detailing that could be changed to match the network's various sub-brands.

"The brand is very very visible, but it's also got that London feel to it," says Jon. It's that dark blue you see used on a lot of suits, but also with the brand popping up where you wouldn't expect to see, where it's on the cuffs, on the back of the neck and on zip-pulls."

The uniform also had to be practical for a network where staff work in very varied temperatures, have to move around a lot.

"We go from the Bakerloo platform at above 40 degrees to about minus 10 [on external stations last Monday]," says Jon. "So we had to create a uniform that can operate under those extreme conditions – while also staying flexible. The extreme conditions of cold doesn't affect all of our stations – so we had to think of how we could use thermal garments, instead of making everyone wear really hot trousers in the summer. So we added in a zip-in fleece. It's a real layering system."

"We need our staff to be comfortable and warm or cool in their work. They're happier in their jobs and provide better customer service."

Staff often have to carry a number of items with them – which could include a seven-inch tablet – so while the trousers have a formal, suit-like cut, they have cargo trouser-style pockets (with the roundel on top, not missing a chance for additional branding).

A lot of the practical design choices come from the amount of time TfL and Hemingway's teams spent talking to staff to work out their needs, wants and bugbears – and incorporate these into the designs.

These conversations also helped diffuse tensions around the new uniforms. While TfL believed that there was a clear benefit for its staff to be clearly identifiable, not all staff agreed. Some wanted to be able to get on with tasks outside of interacting with customers without being interrupted.

It's partially because of this that the most contentious part of the new uniform – the hat – is optional for staff to work. It's not a formal design – Jon describes it as "a mixture of a baseball cap and a soft peaked cap – and has been engineered with practicality in mind, folding up into your pocket and soaking up sweat."

Jon says that "a hat is a real sign of a uniform, it's a sign that it's ok to come up and talk to you" – so TfL has let individual staff members decide to wear them – and when to wear them.

It's another sign of a how a brand as broad as TfL must be. It needs core principles that are clearly understood by all staff – but it needs to be flexible enough for them to make their own choices based on circumstances and comfort levels. There can be few better ways for an organisation like TfL to express its brand – even one that's not selling a fungible service – than with a happy, motivated staff.