Human Factors

Human Factors (Ergonomics):User Interface Design, Workplace Design, Occupational Health & Safety
Human Factors Engineering (“Ergonomics”)
Application of information about physical and psychological characteristics of human beings to the design of devices and systems for human use
Principles apply to design of cars, factory floors, automatic teller machines.
Achieve better productivity and worker safety
Occupational Health & Safety (OH&S)
Legal and moral requirements to provide a safe and healthy place to work
Systems Approach to Productivity
Systems Approach to Productivity
Three areas for Human Factors Design in IS:
User Interface design
Done before implementation but the qualities affect the user experience
See textbook
Hardware design
Mostly done by manufacturers before implementation
Can choose from among available products
Workplace design
Design workplace layout and environmental features
May be neglected or poorly done if not careful
User Interface Design
Design activation of functionality (e.g. menus), input (e.g. forms), and output (e.g. reports)
Today mostly standard ways to do things
Effective user interface design is based on well established principles of human factors:
UI Design Principles
Put the user in control
Reduce the user’s memory load
Make the interface consistent (Mandel 1997 cited in textbook p 173)
Usability Goals
Effective to use (effectiveness)
Efficient to use (efficiency)
Safe to use (safety)
Has good utility (utility)
Easy to learn (learnability)
Easy to remember how to use (memorability)
User Interface Design
Must balance Ease of Learning with Ease of Use
If Easy to Learn
May have few features
May have additional features just for learning (e.g. tutorials, tips, etc.) that are slow or distracting for experienced users
If Easy to Use
May have many extra features, shortcuts, etc that are confusing to new users
User Interface Design Approaches
Commonplace/Standard User Interfaces
Menu-based interfaces
Icon-based interfaces
Forms, widgets (e.g. radio buttons, combo boxes, etc.)
Command-based interfaces
Advanced User Interfaces
Natural language interfaces (type full text)
Pen-based interfaces
Speech recognition
Pen-Based Interfaces
Pen-Based Interfaces
E.g. PDA’s, Notebook tablets
Also pens that scan and upload when writing on paper forms
Pens can be used for data input and data manipulation.
Writing can either be kept as graphic image, or translated to text
Speech Recognition Technology
Computer translation of speech into input or commands
Speaking directly to a computer through a microphone (built-in or separate)
Individual profiles, but big vocabularies
Can require quite a bit of time to set them up & tune them to your speech pattern/accent
Talking to a Voice mail or Call centre application
Wide range of profiles but limited vocabularies
Hardware Design
Monitors can be factors in eye problems as well as productivity issues
LCDs (liquid crystal displays) have better resolution and less glare than CRTs (cathode ray tubes)
Bigger is better!
The keyboard and mouse can be major factors in repetitive stress injuries (RSI) or repetitive motion injuries (RMI)
E.g hand parasthesia, carpal tunnel syndrome
Positioning of keyboard and/or mouse
Keyboard Design
Ergonomic principles
Key pressure – can’t be too hard or soft
Auditory feedback – clicks, sounds
Layout – QWERTY and ASK
Profile – thickness or height
Finish and shape —
Mouse Design
Higher quality mice are much easier to use – more reliable and smooth motion
Also can use other navigation aids
Shortcut keys/menus (hot keys) – avoid using mouse, much quicker to navigate
Notebook buttons
Touch pads
Trackballs (e.g for graphic design software)
Workplace Design
Aim is to better ensure that space design addresses individual worker needs and support work procedures and work tools.
Office layout design can be described or analysed through the AMCO-PACT model.
AMCO = physical aspects related to space.
PACT = practical limitations.

The AMCO-PACT model of office layout
Activity Analysis – what work is being done? who works with who?
Machine Inventory – what do they use now and in the future?
Channel Analysis – accounting for power, communications & networks, ventilation
Organizational Analysis – size and nature of workforce, interactions
Personal Preference – individual needs
Aesthetics – most pleasing way to group workers, location of partitions
Cost – must fit with budget
Time – how long will design be needed? short term rental vs purchase
Can affect productivity directly
Computerization changed everything as too much light makes screen hard to see
Experts recommend
Provide low ambient lighting and increase task ambient lighting
Provide ambient lighting from sources other than ceiling
Build lighting into workstation
Acoustic environment important – printers, computers, combined fan noise, air conditioning
Articulation Index (AI) – acoustic level at which people can work without being distracted by outside conversation.
Sound Control
Solutions not easy to implement
Sound-absorbing materials – cloth, carpeting, ceiling boards or tiles of soft material
Sound-masking systems – white, or low constant background noise to mask other noises
Office layout – 5 foot high wall partitions, isolate noisy equipment
Air Quality
Computers generate heat
Putting a lot of them together with people in a confined space can make a room like a sauna.
E.g. student computer lab 😉
Need decent air conditioning to control for heat and humidity.
Colours and Textures
Colours and textures can affect emotions, senses and thought processes.
Some colours are more soothing than others
Colours can affect perception of temperatures
Colours also affect ambient lighting with lighter colours reflecting more lighting.
Workstation design
Work analysis
Anthropometric concerns
Reach distance
Viewing distance
Monitor Tips
Put monitor directly in front of you and at least 20 inches away.
Place monitor so top line of screen is at or below eye level.
Place monitor perpendicular to window.
Reference: U.S. Department of Labor
Reference has a wide variety of info on Ergonomics
Keyboard and Mouse Tips
Place keyboard directly in front and roughly level with elbows in normal usage position (sitting or standing)
Tilt keyboard appropriately
Place mouse near keyboard, where don’t have to lean forward or hold arm out to reach it
Use armrests to support arms when using keyboard or mouse for extended periods
Use keyboard shortcuts to reduce extended mouse usage
Use adjustable set heights and/or keyboard/mouse heights
Workplace Design
Behavioral Concerns
Personal space
Backs and sides
Eye contact
Occupational Health & Safety
Occupational Health & Safety – Employer Obligations
Each state has laws to regulate occupational safety
require employers to make sure that – as far as is possible – the workplace is safe and health of employees is not damaged. This means:
making sure that the way work is done is safe and does not affect employees health
making sure that tools, equipment and machinery are safe and kept safe (maintained)
Employer OH & S Obligations
making sure that ways of storing, transporting or working with dangerous materials (‘substances’) is safe and does not damage employees health
providing employees with the information, instruction and training they need to do their job safely and without damaging their health
consulting with employees directly or through their health and safety representatives about health and safety in the workplace
checking the work place regularly (‘monitor’) and keep a record of what is found during these checks
Employee OH & S Obligations
Employees also have responsibilities under the health and safety laws. Typically, employees are required to:
follow instructions and rules in the workplace – for example, to comply with instructions designed to ensure that work is carried out safely;
work and behave in ways which are safe and do not endanger the health and safety of anyone in the workplace.
Failure can result in disciplinary action by employer under awards or prosecution under the health and safety law
Role of OH & S Staff
Two main roles:
Strategic approaches to OH & S – policies; developing training programs; risk assessments; statistical analysis.
Operational – work station assessment, presenting training programs, dealing with day to day problems ensuring safety during disaster
managing and coordinating the rehabilitation of staff who have been injured
OH & S Areas for IT
Back and neck problems due to extended computer use
Repetitive strain injuries due to computer use
Eye care due to use of monitors/lighting
Mobile operations – use of laptops, tablets and smart phones

User Interface, Hardware, and Workplace design can be done poorly and affect worker productivity, satisfaction, health, and safety
User Interface design usually receives attention, but may not – usability goals
Hardware design (selection) may be overlooked
Workplace design is often overlooked
OH&S places legal and moral obligations on employers, that are partially met by good user interface, hardware, and workplace design
Further Reading
Elsbach, K.D. & Bechky, B. A. 2007 ‘It’s more than a desk: Working smarter through leveraged office design’ California Management Review. vol. 49, no. 2, pp 80-101.
Hewlett Packard Safety and Comfort Guide

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