Universal Design Principles
Get introduced to the universal design principles of HCI.
What is universal design?
Universal design is when the interface design can easily be understood, accessed and used by all users of diverse age, expertise, and abilities to the maximum extent possible.
Equitable use
This means that the design should be equally useful to users with diverse abilities. All users should have equal access to system functionalities, i.e. users with visual impairment should be provided with equivalent support systems. The system should provide privacy, security, and safety to all users. For example, a website that has screen reader technology will serve the principle of equitable use by being equally accessible to everyone, including people who are blind.
Flexibility
The design should provide multiple ways to perform a task. This will allow the user to perform the task according to their ability and preference. Users can choose methods that best fit their practice, pace, and precision. For example, an application called Serial Box lets the users choose between reading mode and audiobook mode depending on their preference.
Simplicity and intuitivity
The design should feel simple and intuitive to all users of different experience, language, knowledge, and focus. The interface should be kept as simple as possible unless complexity is the requirement of the interface. Informative feedback should be used to make the interface as intuitive as possible. For example, ATM machines have a simple interface with clear indications of options and controls.
Perceptible information
The design should convey information effectively regardless of the user’s abilities or each interaction’s ergonomics. Multiple modes should be used to represent information, i.e. visual, verbal, haptic. Important information should be conveyed in a more substantial way. For example, movies with captions provide perceptible information in the form of verbal and visual cues.
Tolerance for error
Errors and mistakes should not change the system state or impact the interaction. If they have the potential to cause damage, then the design should try to minimize this damage as much as possible. Warnings should be used to prevent potential mistakes. The system should not have any potentially critical situation that can be reached easily by the user. Also, the system should provide assistance to the user while performing critical tasks that require the user’s concentration. For example, when deleting media from an iPhone’s recently deleted folder, the system asks for action confirmation. It also reminds the user that this action is irreversible.
Low physical effort
The system design should be comfortable to use regardless of the user’s abilities. It should not require lots of body movement and should not cause fatigue to the user. Also, it should allow the user to maintain a natural body position. For example, rotary dial phones require more hand movements compared to push button dial phones. Thus, the advanced push button dial phones apply this principle.
Size and space for approach and use
The system should be placed in a way that it is easily approachable by users of all body sizes, mobility capabilities, and postures. Important information should be placed in positions that fall in line of sight and all physical components should be easily accessible for all users regardless of their size or position (seated or standing). For example, ATM machines have controls placed at a perfect height that makes them useful to everyone, including people in wheelchairs.