The feature was not so much a triumphant solution to an ergonomic oversight as it was a pragmatic acknowledgment of an unfortunate and persistent truth in manufacturing: when building something intended for millions of people, a single size simply cannot fit all. Luke Westra, a designer at the Chicago-based design studio IA Collaborative, points out that this workaround exemplifies the daily challenges faced by product developers. “The double tap is the most obvious human factors workaround,” Westra says, highlighting the ongoing tension between sleek aesthetics and human anatomy.
When designers like Westra speak about human factors, they are referring to a specialized field of study primarily concerned with how human bodies interact with their physical environments, a discipline more commonly known as ergonomics. All skilled designers take human factors into account when developing a new product, while those who overlook these critical considerations frequently end up with flawed creations, such as bar stools too low for a standard dining table or office chairs that inevitably induce chronic backaches for the employees who use them.
Decades before Steve Jobs and Jony Ive utilized advanced computers and computer-aided design (CAD) software to sculpt the final form of the iPhone, industrial designers relied on an analog reference tool to help them better understand the intricate proportions of the human body. This comprehensive tool, known as Humanscale, consisted of a set of nine rotating disks packed with more than 60,000 individual data points. By simply spinning the selector in any direction, a designer could watch as a series of precise numbers aligned inside small display windows, immediately revealing the correct measurement values for the specific subject they happened to be designing for at the time.
Throughout the 1970s and 1980s, industrial designers utilized the reference tool as an indispensable cheat sheet to secure quick, reliable data points without having to dig through dense academic literature. However, after MIT Press stopped printing the manuals in the mid-1980s, the physical sets became prized collector’s items, frequently commanding upwards of $2,000 on online auction sites like eBay. Now, Humanscale is making a long-awaited return, thanks to Westra and a dedicated team at IA Collaborative’s Venture arm, who are officially reissuing reprints of the classic design tool, pricing them at $79 per print or $199 for the complete set.
The original Humanscale collection was the product of Henry Dreyfuss & Associates (HDA), the legendary design firm responsible for shaping some of the most iconic consumer objects of the twentieth century, including the classic Honeywell circular thermostat and Bell’s ubiquitous tabletop telephone. Its founder, Henry Dreyfuss, was an early and passionate champion of ergonomic design, and his studio approached the discipline with the rigor of a hard science. Under his guidance, form strictly followed function, and function closely followed data—lots and lots of data.
No product was ever manufactured by the firm without first consulting a comprehensive laundry list of bodily statistics. These included metrics like average human height, arm span, sitting hip width, and the ideal viewing angle from a standard office desk. According to Bill Crookes, who worked at HDA from the early 1970s until the firm closed its doors in the early 2000s, finding this information was historically a major obstacle. “The big problem back then was that data wasn’t necessarily in a nice, easily usable form,” Crookes recalls.
While vital statistical information certainly existed, it was scattered across piecemeal sources. If a designer wanted to know the exact dimensions of the average North American man’s leg, they had to sift through military records. If they needed to determine the maximum decibel level comfortable for the human ear, they had to look up specialized statistics published by the Environmental Protection Agency. Recognizing this inefficiency, one of the firm’s partners, Niels Diffrient, became determined to consolidate this fragmented ergonomic data into a single, highly portable, and easy-to-use tool that creative professionals could physically bring with them out into the field.
Diffrient and his dedicated team, which included Crookes, spent years tediously gathering human engineering data from diverse sources. During their exhaustive research, they learned specific, highly practical details—such as the fact that the average height of a traditional fedora hat was precisely two inches, a vital measurement when taking door clearances into consideration. They combed official government and institutional sources for precise information regarding the physical reach and stature of wheelchair-bound men and women. Furthermore, they meticulously measured the subtle differences in gripping posture when a human hand grasps a cylinder, a ball, or a pencil, subsequently organizing all of these disparate metrics onto the themed rotating disks of the Humanscale system.
As Nathan Ritter, a design researcher at IA Collaborative, notes, the creation of the tool was an intensely physical and detail-oriented labor. “They laid out every little bit of info on these tools by hand with a square triangle and a compass on a drafting table,” Ritter explains.
Illustrations printed directly on the front and back of the disks depicted humans and their various body parts in a multitude of postures, with guiding arrows annotating dozens of critical measurement points. Rotating the disks filtered the underlying data sets, allowing a designer to isolate information specific to women, men, and children across their various demographic percentiles.
Humanscale stood out as a true masterpiece of information design, and it can arguably be considered one of the very first interactive data visualizations ever created. Although it is now viewed by many as a historical relic, it remains widely respected among industrial designers as the gold standard of human engineering statistics. In the decades since its discontinuation, the physical disks have largely been replaced by more technologically advanced tools, such as proprietary digital ergonomics databases that modern design firms often license for thousands of dollars annually.
For the team at IA Collaborative, allowing the groundbreaking Humanscale disks to fade permanently into obscurity would have represented a massive missed opportunity. Ritter emphasizes that the core concepts behind the tool remain entirely relevant to modern creators. “They’re still just as relevant today as when they were just launched,” Ritter says.
The studio’s designers are starting their revival effort by reissuing the original physical disks and accompanying books. However, they eventually plan to take the project a step further by digitizing the entire body of information and developing a modern interactive interface for the data. The team believes that most contemporary designers could benefit immensely from having a straightforward, tactile tool to help ensure their creations are tailored directly to the actual people who will use them.
As Westra notes, the temptation to create in isolation is a constant hazard in product development. “You can design anything in a vacuum,” Westra says. “Pero si no estás considerando a las personas que lo van a usar, no van a tener una gran experiencia.”
