1.7.2. Design Goals

Definition: The design is useful and marketable to people with diverse abilities.

Design Goals:

• Avoid segregation or stigmatization of any users.
• Provide the same means of use for all users — identical whenever possible; equivalent when not.
• Ensure privacy, security, and safety are equally available to all users.

Examples in Civil Engineering:

• Automatic doors at entrances allow both people with disabilities and able-bodied individuals to enter without assistance.
• Digital pedestrian signals with audio and visual outputs benefit both visually impaired and hearing-impaired users.
• Multi-height counters in public buildings or customer service points that serve people in wheelchairs as well as standing individuals.

Equitable use emphasizes the importance of designing with all users in mind. It ensures that no one feels left out or singled out because of their abilities. This means providing options that are equally usable for everyone, whether they are in a wheelchair or able-bodied. For example, instead of just having steps to enter a building, an automatic door allows both wheelchair users and those who walk to enter easily together.

Think of a restaurant that provides both braille menus for visually impaired customers and standard menus for everyone else. By doing this, the restaurant is ensuring equality in access to information and experience.

Definition: The design accommodates a wide range of individual preferences and abilities.

Design Goals:

• Provide choice in methods of use.
• Accommodate right- or left-handed access and use.
• Facilitate user accuracy and precision.
• Adapt to the user’s pace.

Examples in Civil Engineering:

• ATM machines with tactile keypads, audio outputs, and adjustable screen angles.
• Staircases with handrails on both sides to support left and right-handed individuals or people with reduced grip.
• Adjustable lighting in public spaces that helps individuals with varying degrees of visual sensitivity.

Flexibility in use means that designs should cater to the different ways individuals prefer to interact with them. This could involve offering right or left-handed options, which is important for users who may not have the same strength in both hands. Adjustments in environments where people operate machinery or technology ensure that everyone can utilize these features effectively, depending on their needs and preferences.

Imagine a kitchen designed with movable countertops. For someone who prefers to work standing up, they can adjust it to a higher position, while someone who prefers to sit can lower it. This flexibility makes the kitchen more usable for everyone.

Definition: Use of the design is easy to understand, regardless of the user’s experience, knowledge, language skills, or current concentration level.

Design Goals:

• Eliminate unnecessary complexity.
• Be consistent with user expectations and intuition.
• Accommodate a wide range of literacy and language skills.
• Provide feedback to the user.

Examples in Civil Engineering:

• Pictograms on signage that convey messages universally (e.g., restrooms, exits, emergency information).
• One-touch pedestrian crossing buttons with LED feedback.
• Color-coded and labeled floor plans in buildings for easy navigation.

Designs should be straightforward, meaning they are easy to navigate and understand. This principle is crucial because it helps users who might struggle with complex instructions. For instance, signs that incorporate images (like a toilet symbol) help everyone, regardless of their language or reading skills, understand the message quickly.

Consider your smartphone. The icons are universally understood— a phone for calling, a camera for photos. Even if you’re unfamiliar with the device, you can figure it out just by looking at those images, making the technology accessible to everyone.

Definition: The design communicates necessary information effectively to the user, regardless of ambient conditions or the user’s sensory abilities.

Design Goals:

• Use different modes (pictorial, verbal, tactile) for redundant presentation of essential information.
• Provide adequate contrast between essential information and surroundings.
• Maximize legibility of essential information.
• Differentiate elements in ways that can be described (i.e., make it easy to give instructions or directions).

Examples in Civil Engineering:

• Tactile paving on footpaths and at pedestrian crossings for visually impaired individuals.
• Emergency evacuation signs that include both audio alarms and flashing lights.
• Contrasting colors and textures on stairs and walkways to enhance visibility for the elderly or visually impaired.

Perceptible information focuses on ensuring that users can access crucial information through various methods, such as sight, sound, and touch. This is particularly relevant for individuals with different sensory abilities. By providing information in multiple formats, designers ensure that everyone can understand vital messages, regardless of their sensory capabilities.

Think of a fire alarm that rings loudly and simultaneously flashes lights. This dual alert system helps both those who can hear and those who may be hearing impaired to respond quickly in an emergency.

Definition: The design minimizes hazards and the adverse consequences of accidental or unintended actions.

Design Goals:

• Arrange elements to minimize hazards and errors.
• Provide warnings of hazards and errors.
• Provide fail-safe features.
• Discourage unconscious action in tasks that require vigilance.

Examples in Civil Engineering:

• Railings and barriers on elevated walkways or balconies to prevent falls.
• Non-slip surfaces in wet areas such as bathrooms and swimming pool zones.
• Gradual curbs and ramps with tactile warning strips near vehicular roads.

Tolerance for error is about making designs safer and easier to use by preventing potential accidents. This includes creating environments where even if users make a mistake, the results are not harmful. For instance, if someone slips on a wet floor, a non-slip texture can reduce their chances of falling. This is especially important in places where safety is a priority, such as public buildings.

Imagine driving a car that has automatic braking when it detects a potential collision. This fail-safe feature helps prevent accidents even if the driver makes a mistake, thus enhancing safety.

Definition: The design can be used efficiently and comfortably, with a minimum of fatigue.

Design Goals:

• Allow user to maintain a neutral body position.
• Use reasonable operating forces.
• Minimize repetitive actions.
• Minimize sustained physical effort.

Examples in Civil Engineering:

• Lever-style door handles instead of round knobs, which require less grip strength.
• Push-button elevators placed at accessible heights.
• Public washbasins with motion sensor faucets.

Designing for low physical effort means creating products and environments that are easy to use without causing excessive fatigue. This is especially important for individuals with limited strength or mobility. Features like lever handles and motion sensor faucets are designed to help users operate them with minimal physical exertion.

Think of an office chair with adjustable heights. A person can quickly pull a lever to change its height without needing to exert much strength. This ease of use helps reduce fatigue, especially during long hours at work.

Definition: Appropriate size and space is provided for approach, reach, manipulation, and use regardless of user’s body size, posture, or mobility.

Design Goals:

• Provide a clear line of sight to important elements for any seated or standing user.
• Make reach to all components comfortable for all users.
• Accommodate variations in hand and grip size.
• Provide adequate space for assistive devices or personal assistance.

Examples in Civil Engineering:

• Wide doorways and corridors to accommodate wheelchairs and mobility aids.
• Accessible parking spaces with adjacent access aisles.
• Restrooms with turning space for wheelchairs and grab bars for assistance.

This principle focuses on ensuring that there is adequate space for all users to interact with elements in the environment. Size and space should consider not just the average person but also those with different body sizes and mobility requirements. This means designing areas where wheelchair users can easily maneuver, and people have enough room to comfortably use a space.

Imagine a restaurant with wide aisles and spacious tables. Someone in a wheelchair can move easily between tables and approach the cashier without feeling cramped or blocked. This thoughtful design makes dining enjoyable for everyone, rather than just those who can easily walk through tight spaces.

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