prevent discrimination by design

Products are generally made for as many people as possible to easily use. If as many people as possible can sit comfortably in a chair, then the manufacturer only needs to produce one version. The same applies to roller coaster seats: if as many people as possible can safely ride the roller coaster, the theme park can sell more tickets. Overweight people often fall by the wayside in these kinds of situations. Students Daniëlle Klomp and David Vainer wanted to do something about this with their final projects for their Bachelor's studies in Industrial Design Engineering at TU Delft. "Designing for overweight people is still quite taboo," says Vainer. "While everyone has the right to be able to sit comfortably. You have to want to design for this group as well." Especially because losing weight is not an option for everyone, the students learned. "Some people don't realise that it's much more than just eating a lot and not exercising much," adds Klomp. "The problem is that overweight people are often excluded. For my project, I read blogs by overweight people where they share how they experience a visit to an amusement park. I would read about situations where someone does not fit into the roller coaster seat and has to get off on the other side of the roller coaster train, a veritable walk of shame. Whereas, of course, everyone should be able to enjoy such a ride!”

The solution to inclusive design lies in the use of data on measurements of the human body. These so-called anthropometric data can be used by designers to ensure that products fit as many different body sizes as possible. The free DINED platform* of the Faculty of Industrial Design Engineering makes these data available to designers. "But for overweight people, the necessary data sets are often missing, preventing designers to design adequately for this group," says Klomp. "That's why we started taking surveys at an obesity clinic in the research phase of our projects," adds Vainer. "This showed that stigma is actually the biggest problem, in addition to practical problems with especially chairs." Not only office chairs, but also benches in public spaces and waiting rooms, roller coaster seats and all kinds of other seating areas need to be looked at. Klomp and Vainer have set to work on the challenge of creating inclusive seating arrangements in their own way.

A comfortable roller coaster ride for all

Klomp researched how seats in roller coasters could be designed to be more inclusive, as these are now places regularly avoided by overweight people. "If I could prevent such a walk of shame with my design, I would love that," she says. The challenge in achieving this lies not only in increasing the seating surface area for the passenger but especially in the way the restraint closes. "Tall people are often also bothered by the restraints," Klomp discovered. "Amusement parks want to allow access to the roller coaster for as many people as possible, and customization for a small group of people is pricey. Roller coaster designers work all over the world and apply the same rules everywhere, which makes exclusion a risk. I have come across only one amusement park where it was indicated that the roller coaster was suitable for a larger weight. For my project, I look at how, for example, two or four seats could be adjusted instead of the entire train. Then the extra cost is not too high and the specialised parts are easier to replace. When my product is finished, I also hope that it doesn't come across as a 'different' seat on the roller coaster, but that it looks very natural."

Waiting at the doctor's office

Stigmatisation can not only limit the accessibility of an amusement park but can also be a barrier to going to the doctor. Vainer: "Going to the doctors is no fun, but it's even less fun if you're wondering if you will be taken seriously. And if you can't just sit in the waiting room..." The surveys showed that a large proportion of respondents have problems with chairs, such as chairs in waiting rooms. These kinds of generic spaces are often also difficult to access for people with disabilities. Vainer, therefore, decided to work on a seating unit for all sizes, an object that would not look out of place in a railway station either. "I tested several ideas and discussed them with different experts. With a seating expert, a physiotherapist, a furniture manufacturer, designers, a general practitioner and even a specialised nurse, I researched people's needs. Even with all those needs mapped out, it was quite difficult to make choices. For example, the average sitting height is 45 cm from knee height to the ground, but older people like to sit a bit higher. But that is not comfortable for shorter people. During the design process, the question was constantly: what size should I take? Who do you exclude or not?" This train of thought has resulted in a flexible seating element, where the backrest is adjustable and can also be used as an armrest. An undulating seat provides different seat depths, so the user can choose what is most comfortable. "And I also wanted it to be produced in a circular way. That does come at a price," Vainer adds. "But it's also about the overall picture: everyone can sit comfortably on this sofa, without stigma. The most important goal has been achieved."

Human measurements in practice

Good design in practice does not just prevent stigmatisation. Issues such as safety, materialisation, durability, seating comfort and health are also part of the programme of requirements. . "A good design helps you to sit comfortably and healthily. DINED is an important source to achieve that in practice," says Arnoud Vlieger. He is both head of product development for chairs at Ahrend and chairman of the NEN standards** committee for office and school furniture. In his role with the standards committee, Vlieger comes across the importance of the human dimension. "The data from DINED clearly show that the Dutch working population is much taller than their European colleagues. As a result, seat dimensions must be adjusted accordingly, such as a much longer backrest for the same level of comfort for an employee." The data from DINED has been used to make additional regulations so that designs are made to be as inclusive as possible. "If you apply the standard, you design for everyone. If the design is made to measure and falls outside the norm, specialised companies can adapt existing chairs with specific components. That way, chairs become comfortable for everyone," concludes Vlieger.

Designing for everyone

Designing as inclusively as possible requires products that can be customised. At the same time, nobody likes to be stereotyped. This is the main realisation of student David Vainer: "Someone who is overweight doesn't always want to sit on the biggest chair, because that actually stigmatises people. If you really want to design inclusive furniture, you have to make something that can be used by all people in the same way. Anything that has to be different can be embarrassing. As a designer, you have to think creatively and work outside the box to avoid that. Ask yourself the question: what can people do with my product, if my product is not made for them?" With tools like DINED's resources, products can not only be customised as much as possible but also tested. Klomp sketches an example: "For another project, I designed a kind of helmet that had to sit securely on your head. Using DINED's mannequin function, I was able to place the design virtually on someone's head in 3D and test it. Without DINED’s features, this would not have been possible.”

 Measurements for the future

Arnoud Vlieger sees even more opportunities for using the human dimension in design. "DINED provides hard data, but it's the soft values in between that are important for quality. Especially when it comes to office chairs. People still think of old-fashioned offices with typewriters and 60,000 workstations, where employees sit on their office chairs all day. Whereas the new reality is that people work from home more often. In the office, they meet to discuss things in an increasingly informal setting: standing with a cup of coffee, on a pouffe or sofa, in a homely style. If the office is primarily about health and feeling comfortable, how should we then link human dimensions to products?"

Vlieger sees opportunities for expanding databases for designers such as DINED with information about human health, such as the need for daylight, fresh air, and good blood circulation. "With such information, we can develop better products that not only sit comfortably but also actively contribute to good health." In the meantime, DINED is continuously updated with new datasets, so designers can use the correct measurements for today's people. Klomp and Vainer are finishing their bachelor's degrees and will take the importance of human dimensions with them towards their follow-up studies, respectively the master's in Integrated Product Design and a switching semester focused on Biomedical Engineering. Vainer: "I'm going to see if I like doing something else, but just like in my studies in Industrial Design Engineering and DINED, the focus on the human being remains."

*DINED is the anthropometric database of the Faculty of Industrial Design Engineering at TU Delft. With the free information on human dimensions, designers can create better products. The online information system is used by 50,000 users worldwide to conceive a more inclusive and human-centred design. In 2014 it was awarded the Dutch Data Prize.

DINED's tools range from tables with averages of various human dimensions, such as overhead reach distances and thigh and hip circumferences, to 3D and 4D tools and techniques. With additional tools, body dimensions can be compared (Profiler), 3D models of differently sized human bodies can be generated (Mannequin), and the relationship between different dimensions and the designed product can be determined (Ellipse).

**The European 'CEN' is the standard with which products must comply, so that a certain quality can be guaranteed. This does create a problem in practice. The Dutch working population is a lot taller than the average European. Therefore, the industry has drawn up the Dutch Practice Guideline, the NPR 1813:2016. The neutral data from DINED have been used to develop the NPR. The European standard and the supplementary NPR are still revised every five years, if necessary. If the Dutch population changes and, for example, becomes taller or heavier on average, the standards change accordingly. Chair manufacturers then adapt their designs accordingly.

Header image:  Circularly produced seating unit with individual components to fit all bodies. The backrest consists of individual components that can also be used as customised armrests. The undulating seat creates different seat depths, so everyone can choose the most comfortable place to sit. Image by David Vainer (2021) 

original publication [dutch]