Article #9, April 6, 2005

”Besides displays and controls, what other Interfaces do you design?”

Human Factors professionals are hopefully directing their efforts into designing interfaces between systems and end users and focusing their research into collecting useful data that can be directly applied by engineers and designers.

As mentioned in the previous articles, the two main interfaces that common people might guess are the displays that inform a user of the status of the system and the control devices which allow the end-user to modify the status of the system to a normal functioning behavior.

Since end users are the target and they do determine the success of any systems, consequently, for any system to be accepted, purchased and retained the end-user has to be able to operate the product easily, efficiently, without undue training, be relatively affordable and safe for use by the intended users.

Let us consider the various stages that the designs of a system go through in order to effectively deliver on its purposes and objectives:

First:  To define the objectives and specifications we have to determine the user’s needs and characteristics, organizational structure, work flow, and human performance measurement procedures and parameters. An expert ergonomics is trained to study and analyze all these requirements.

Second:  Next, we have to define the functional and operational requirements.  An expert ergonomics can and should participate in this stage.

Third:  The basic design stage of function allocations to operators or machines, work procedures and performance feedbacks are intrinsic knowledge to ergonomics.

Fourth:  Designing interfaces and work areas are the primary training of ergonomics engineers.

Fifth:  Designing facilitator material such as developing staffing, instructions, performance aids and training are the expertise of ergonomics.

Sixth:  Evaluating and testing specifications and performance are within the training of human factors/ergonomics professionals.

All interfaces that help a user operate a product or subsystem according to the above criteria are part and parcel of the responsibilities of Human Factors professionals.

Consequently, the interfaces within the Human Factors professionals’ capabilities and training are mainly, workstation design, instruction manual, job aids design, training programs and evaluation of systems.

Many other job descriptions during the first stages of system design and operation are within the knowledge and training of Human Factors as well: mainly, task analysis, operation-sequence diagrams and allocation of functions and task to either human operators or machine, or automated sections in systems.

Obviously designing an interface for a mandated trained user like an airplane pilot or a nuclear power plant engineer is easier, complexity of the system being comparable, than designing for common people of all gender differences, stature, age, race and cultural variety.

Designing operation and maintenance manuals attached to any product is an important job description that could promote the acceptance and usage of a specific product.

Usually, the instruction manuals contains safety signs, messages and pictorial for the main steps in the operation and thus enhancing safety and avoiding unnecessary litigations down the road.

Designing training programs for the operation, maintenance and repair of products for targeted personnel are within the job description of Human factors graduates.

Evaluating systems’ performance for essential criteria, including training time, safety built-in design, understandability of the manuals and acceptability are within the training proficiency of Human Factors graduates.

One of the widely promoted job descriptions is designing workstations.

Workstations design is not about just chairs, tables, keyboards, computer screens and the dozen other gizmos related to a fully functional workstation from communication to printing to audio-visual facilities.

A functional workstation has to account for the tasks involved, the positions of the operators, the arrangement, the lighting environment, and the entrance and egress facilities that could harm the operator.

A Human Factors should evaluate a workstation on the health and safety criteria of a designed workstation as well as its operability.

For example, we have already talked about repetitive trauma disorders, pains in various parts of the body and permanent health problems.

Note:  A student version found that designers of menu interface had difficulty with 91% of the guidelines. Analyses of the cause of the users’ errors were studied for recommendations.