Brian Russell

Human Factors

Exam expectations

Issues associated with Human Factors are regularly tested in the written paper

Human Factors Human factor issues are concerned with the limitations

and abilities of humans and the relationships they have to products. They are often regarded as the most important considerations when designing. Human factors might be broken down into three different groups:

Physiological factors Psychological factors Sociological factors

Physiological factors

• Physical limitations

• How the body moves

• Hand/eye coordination

• Strength

• Size

• Stamina

Anthropometrics

• The study of human measurements• Numerous data available• Need to be selective• Match target group

Standard clothing sizes

Anthropometrical information is used to standardise clothing sizes but the way they are labelled varies between different countries.

5th-95th percentile• Ignore the extremes • Top 5% and bottom 5% taken out• Consider the rest as a normal range• Be selective – tallest for doors, shortest for

chairs?

Ergonomics

The term ergonomics comes from the Greek words “ergon, meaning work, and “normia” which relates to organisation and was first used to study how military personnel operated machinery. Since then it has been broadened to consider how humans interface with a wide range of products, architecture, work-stations etc.

Ergonomics

• Efficiency - people to their products• Efficiency - people in their working

environments• Comfort• Ease of use• Safety…

Anthropometrics is a major issue when designing hand held devices such as this. Symbols need to be easy to understand, buttons easy to operate and the screen clear to read.

Using anthropometric data

Anthropometric data is a major factor in ergonomics

Ergonomes

• Ergonomes are models of people in normal proportions

• Sometimes they are full size and sometimes to scale

• They help designers make decisions about sizes, positioning etc.

Working trianglesMost efficient working spaces:• Reach envelope• Production lines• Kitchens• Offices

Organising the different activities to reduce the amount of movement a person needs to make are important considerations.

Working triangles

• One of the best examples of working triangles is the driving position in a car. Because the driver is in a fixed position every control needs to be in reach. We sometimes refer to this as the reach envelope.

Adjustment

• Cycles

• Car seats

• Office chairs

• Clothing…

Many products need to adjust to different sizes:

Psychological factors

• How we taste• How we smell• How we feel• How we see• How we hear

Designers have to take into account how the human mind works when designing products to ensure that they are easy to use. Our senses are constantly providing our brain with information.

How we taste

• Sweet

• Sour

• Bitter

• Salty

• Spicy

• Bland…

Food products

• As far as food products are concerned designers plan for smell, taste as well as colour and visual appeal.

• The dietary needs of different groups of consumers whether for health reasons or cultural or religious beliefs are major issues when designing food products.

• This needs to be balanced with the health concerns of ensuring that the daily intake of food is both matched to the person and is part of a healthy diet.

How we smell

• Enjoy• Disguise• Pleasant• Unpleasant…

How we feel

• Textures• Grip• Shape• Temperature• Comfort…

Hand co-ordination

• Many products are designed to work with touch alone. The visual aspects of the computer mouse are really not very important, it is how easy it fits the hand and how easy it is to operate which are the vital considerations.

Tools• The shape, size and grip are important

considerations in the design of many hand tools

How we see

• Colour• Moods• Identity• Signs & symbols• Information• Analogue/digital• Lighting levels• Field of vision…

Using colour• Colours can influence moods or feelings.

This is used when designing interiors such as entrance spaces where a warm and welcoming atmosphere is needed or offices which are cool and calm.

• Colour is often chosen to help the consumer understand the product easier.

• Safety issues are often coloured red, yellow or orange.

• Colour is used to suggest issues such as cleanliness, which is why many kitchen appliances are white.

How we hear

• Sound• Feedback• Noise reduction• Relaxing• Warning

Noise can be very disturbing

Sound• The ears continually receive information from

all directions.

• Sound can be used to provide warnings or feedback with products. Whistling kettles, reversing trucks and car indicators are all examples of products which provide audible feedback.

• Sound is built into products such as watches and electrical switches for reassurance that the product is working.

Reacting to information

• The driving controls in a car is a good example of how we have to react quickly to a wide range of information

Sociological factors

• Personal space• Privacy• Access• Toilets• Cleaning/maintenance• Safety• Disability• Transport

Personal space

We live and work in groups but need:• our own space• privacy

Special groups

• Elderly• Disabled• Children• Athletes• Vegetarians• Diabetics• Religious groups…

Disability• We are all disabled at some times in our lives• Sometimes temporary• Sometimes very mild• For some people a serious disability is there for

life

Coping with physical disability

• Wider doorway• Lower sink/bath• Handrails• Alarms

Access

Many products cause access problems• Medicines• Food and drinks• Transport

Disabled Access

• A major factor when designing public transportation systems and buildings

Health & safety

• How easy to swallow?• What temperature does skin burn?• How much can we safely lift?• How close do uprights need to be on a

child’s cot?• What materials are toxic?

Risk Assessment

Stereotypes

• Similar age?• Similar values?• Similar beliefs?• Similar lifestyles?• Similar size range?

Would we call this a target market?

Different values/beliefs

• Religious

• Cultural

• Moral

• Social

Social issues

• Trying to copy the catwalk models• Size Zero is not “normal”• “Normal” is a very large range

Exclusive design

Targeted at a narrow range of people:• Young• Wealthy• Female…

Inclusive design

An impossible aim?

• Suitable for all

• Inexpensive to purchase

• Inexpensive to run

Research and testing

• Find out as much about the user as you can before you start

• Products should be easy to use and easy to understand

• Consumer trials needed

• Human factors are the

most important ones!