Recent Changes - Search:
  • Welcome

'We have 3 guest/s online'

Content Areas

Other Areas

Our Sites

Save to Save to LinkAGoGo Save to Ma.gnolia Save to Yahoo! My Web

edit SideBar


news article on the smallest seats ever designed for air travel!

6.1.1 Define ergonomics, anthropometrics and percentile range.

The application of scientific information concerning the relationship of human beings to the design of objects, systems and environments.
The aspect of ergonomics that deals with body measurements, particularly those of size, strength and physical capacity.
Percentile range
That proportion of a population with a dimension at or less than a given value.
'Workstation' 'Computer Ergonomics'

Ergonomics From the Greek words "ergon" (to work) and "nomoi" (natural laws). Ergonomics is an application of science dedicated to designing equipment. The purpose of ergonomics is to improve productivity by minimising negative factors such as discomfort or fatigue.

Anthropometrics From the Greek words "anthropos" (humans) and "metros" (to measure, measurement). Anthropometrics (anthropometry) is the systematic study of the measurement of humans. Anthropometry became a major aspect of design after World War II, when designers came across design-related problems associated with human movement.

Percentile range In a design context, designing for a percentile would be designing for the size that is greater than or equal to a certain percent of a size. For example, designing for the 90th percentile would be designing for the largest size that is greater than or equal to 90% of all possible sizes.

Graph depicting the 5th, 50th, and 90th percentile range in anthropometry

6.1.2 State that ergonomics is multidisciplinary, encompassing anthropometrics, psychological factors and physiological factors.

Ergonomics, being based on the way humans interact with products, must explore all aspects of said interaction. This includes measurements (anthropometrics), physical comfort (physiological factors), and mental/psychological comfort (psychological factors).

6.1.3 Describe a design context where the 5th–95th percentile range has been used.

For example, mass-produced clothing.

Here these diagrams show the percentile range of which mass produced clothes or any design context that uses the entire percentile range. from the 5th to the 95th percentile. The annotated diagram shows the differences of short and tall people and the difference of pregnant and none pregnant women. this shows that mass produced clothes must be made for every percentile range so that everyone can buy them.

Mass produced clothes are the main design context where the 5th to the 95th percentile range has been used.

  • comfort is important
  • clothes need to fit right
  • a range of percentiles are used
  • NB manufacturers use a range of percentiles when safety (including health) and comfort are important in the product.
    • eg motorbike helmets (safety), shoes (health & Comfort).

6.1.4 Describe a design context where the 50th percentile has been used.

For example, height of a desk.

Height of a desk is an example of the 50th percentile range is only comsidered.

  • The desk will fit most of the population.
  • The 20% and 80% can still use them
    • the short people may have to raise arms higher
    • tall people will need to bend down a little
  • Most people don't sit at a desk for long periods of time
    • if they do then adjustable desks or chairs are used
  • NB safety & comfort is not crucial

6.1.5 Explain the limitations of using the 50th percentile as a means of designing for the “average” person.

The 50th percentile refers to one particular dimension. For example, someone may be average in height but not average in other dimensions.

The assumption is made that every person in the 50th percentile has perfect, equal ratios. Such is not the case, therefore is a limitation of designing for the "average" person.

Means designing for the “average” person

  • Maybe average in height
  • not average for waist size
  • jeans or pants are a good example as you can get a 32" length but a 34" waist
The Vitruvian man, a rendition of the perfect man with
perfect dimensions and ratios.
Pants with average waist width but with thicker leg width.

6.1.6 Identify specific design contexts where the designer would use percentile ranges for particular user groups.

For example, toys for young children.
Hats or helmets. Knowing the percentile ranges of sizes and circumferences of heads of different user in order to make sure that the desired user group will be able to wear and thus purchase the involved design.
School desk chairs. Those seats that have to be designed for the elementary, middle and high school user groups
Lego vs duplo-blocks are also specially aimed at user groups. Lego blocks for instance, are small, with sharp edges and small connecting holes which makes the design more complex and the blocks harder to connect with each other. Consequently, it is destined for children age five and over. Duplo-blocks on the other hand are more simple in design, with a bigger size and softer touch, they are designed for children up to three years old. Also, the duplos are big enough not fit in the mouth or throat of a toddler.
Duplo versus Lego blocks

6.1.7 Outline the significance of psychological factors (smell, light, sound, taste, texture and temperature) to ergonomics.

Individuals react differently to sensory stimuli. Efficiency and comfort are affected by such factors.

People react differently to stimulus

  • affects efficiency of the task at hand or the comfort zones
  • reduce productivity or distract the person
  • Ergonmics4schools website has examples the affects
  • For example: if it is to hot, you get sleepy, cant concentrate, get itchy and want to move around
  • Find different peoples temperature "comfort zone". for more information visit Ergonmics4schools

6.1.8 Outline physiological factors that affect ergonomics.

For example, bodily tolerances such as fatigue and comfort.

Bodily tolerances (how much can the body withstand)

  • if the body has to undertake physical work
  • the body tires or physical discomfort can happen
  • For example, if it is difficult for a person to turn a knob to open cans then they will tire very quickly which leads to mistakes happening, efficiency dropping and eventually accidents and injuries. That means the workers may be absent and cost the company money.

6.1.9 Discuss the influence of perception when collecting data relating to psychological factors.

Quantitative data may be used in a design context relating to psychological factors, but individuals vary in their reaction to the data. For example, one person will find a room temperature comfortable while another person will find it uncomfortable, though the temperature is constant.

People feel and react differently to psychological factors

  • therefore the recorded data will vary
  • too hot/cold yet the room temp hasn't changed
  • will be difficult to get it right while desiging considering only quantitative data


Bulleted list and italicised paragraphs are excerpted from Design Technology: guide. Cardiff Wales, UK: International Baccalaureate Organization, 2007.

Images are clickable links to its location.

1.1.1 Citations of Sources:

  1. Anne and Robert Rickover, web managers. 31 August 2008.
  2. August 2008.
  3. The Skeptic's Dictionary. Todd Carroll, Robert. 31 August 2008.
  4. Wikipedia: The Free Encyclopaedia. 31 August 2008.
  5. Inverarity Laura, author. 31 August 2008.
  6. BBC-h2g2-Ergonomics. 31 August 2008.
  7. Connexions. Lane, David. 31 August 2008.
Edit - History - Print - Recent Changes - Search
Page last modified on October 21, 2013, at 07:48 PM