Concept and principles

Anthropometric data consists of  measurements of the human body--height, weight, arm length, etc. Datasets of anthropometric measurements can come in various forms, populations groups, quality, and sample size . Therefore, the designer should use a data set that is best suited to their design goals.

Primary data is data about the specific target audience that is gathered first hand by designer. This data can also be considered survey data and tends to consist of a relatively small numbers of samples. 

Secondary data typically comes from data sets that are produced by government agencies or research groups and have a relatively large sample size.

Anthropometric data can consists of two types of measurements: Static and Dynamic

• Static Measurements: measurements of length between points on a body.

• Dynamic Measurements: measurements of reach, movement, or strength. These measurement would be used to determine how a person moves in a space (i.e. reaching for a lever from a seated position, turning a wheelchair around, etc.) or how much force is required to complete an action (i.e. opening a lid, turning a wheel, etc.).

Reach

Regarding reach, measurements are often differentiated as either normal reach or maximal reach. Normal reach would indicate a the distance a user could comfortably extend their arm, while maximal reach indicates the maximum distance they could extend their arm.

 The implication is that normal reach would indicate a distance where objects or controls are comfortable and easy to reach with minimal physical stress, and where they can be accessed easily and repeatedly; maximal reach, on the other hand, would be accessible, but would require some effort and not be ideal for repetitive or frequent actions.

Percentiles and Percentile Ranges 

When designing a product or service, designers need to determine which Percentiles their product will serve. From this, they can determine specifications such as the physical size or fit, or how much force is required to operate a button.

As each human has distinct physical and mobility characteristics, simply averaging the data collected will not ensure that accessibility or comfort for users. Through collecting primary and secondary data, designers can determine which range of users they need to design for.

What is a percentile? A percentile is used in statistics to show the value below which a certain percentage of a group falls. The 25th percentile is the value at which 25% of the population are at or below.

The 50th percentile is the point at which people half the people in the group (The mean) would be 130cm tall or less would be accommodated. Likewise, if the designer had used just the 5th percentile as their reference, then only those 115cm or shorter would be accommodated.This is where designers must carefully consider who they are designing for and what measurements are important. The design context is important. Consider the 50 percentile (130cm). Even though it is the mean of the user population, it does not include anyone who is above this average.

Application of Percentiles in Design

Consider these different design contexts and how height would play an important role in the design considerations:

• An opening for an elevator:

• The height of a shelf on a wall

• Height of a safety railing

• The location and height of an elevator button

In each of these situations, the designer would need to identify which percentile would provide them with the data to meet the design goal. Do they need to consider the tallest or the shortest user in their design context?

FACTORS THAT INFLUENCE ANTHROPOMETRIC MEASUREMENTS

Factors such as Age, Gender, Ethnicity can influence these measurements. For these reasons, designers must carefully consider the source of their data sets and whether they are applicable to the design context.

USING ANTHROPOMETRIC MEASUREMENTS 

Follow these steps for identifying the data and percentile ranges you will use (adapted from here).

1. Decide who you are designing for: Identify the user population (adults, men, women, children, etc.)

2. Decide which measurements are relevant: Identify the static and dynamic measurements that will be necessary for you to consider in your design (height, reach, grip strength, etc.)

3. Decide what percentile you need to design for: Will you design for the average user (the 50th percentile), or for the extremes (the 5th or 95th percentiles)? Depending on your design and user population, you need to select the relevant data to guide your design specifications.

Sources and Databases of Anthropometric Data

• Size Korea: Korea Datasets

  • Human Scale: Calculator

• WHO Growth Reference Data: World Health Organization data of growth rates for children 5-19 years old

• List of Data Sources: Collected by Tufts University; wide variety of sources

Resources

• Openerg.com has lots of information about calculating, measuring, and apply ergonomics

• ergonomics4schools.com has detailed explanations and descriptions for how ergonomics can be applied

• Penn State Open Design Lab: Online links to data, calculators, models, and guidelines

• NASA: Anthropomorphics and Biometrics: Information about human body size, posture, movement, surface area, volume, and mass

• Knoll Office furniture: 

• Allsteel: Ergonomic Principles in Design: PDF outlining principles and concepts of ergonomic design and how it is applied to office seating

• Human Ergonomics: Website of an ergonomic consulting firm with detailed resources on a range of issues and principles related to ergonomics and design. Many links to databases, health and safety information, and standards.

Research

• The Quarterly of Human Factors and Design: An online journal and blog about issues related to human factors and ergonomics

• Herman Miller: Innovations in supported seating: PDF or HTLM: White paper outlining the benefits of ergonomic seating in the workplace

• Herman Miller: The Eyes Always Win: PDF or HTML: White paper outlining the heath implications of poor monitor placement in the workplace