Value of HF

This page is intended for those who ask “What benefit do I get from adding human factors to my program?” Put another way, “What value does the Human Factors Branch provide?”

Human factors engineering can also be thought of as value engineering as the goal is to ensure that systems, equipment, and procedures provide the maximum value to the users, and ultimately to the NAS customers and stakeholders. Successful systems, equipment, and procedure development requires an understanding of the users, and understanding of the goals, and an application of human psychology to maximize usability and minimize errors.

Ease of use

When people experience difficulty using a system, system acceptance, user satisfaction, and efficiency decrease while errors and workload increase.

Try it before you buy it

Human factors prototyping and simulation can allow new systems designs and concepts to be tested and improved before making costly investments in operational hardware and software.


Simplifying the systems and equipment that users interact with reduces costs and enhances efficiency and safety.


Consistency of interaction produced by applying human factors principles increases the predictability of the user interface, reducing training time and mental workload by allowing the user to capitalize on known usage patterns providing successful interactions in the face of features encountered for the first time.

Pay now or pay more later

Involving human factors early in the process saves money by reducing redesign costs. Changes to a system costs less when made early in the development process. If human factors issues are not addressed users may refuse to use a system. A general rule of thumb is that for every $1 spent on human factors early in the development cycle, $100 is saved on fixing the problem once the system is released (Gilb, 1988). Proper human factors engineering can prevent many problems that cause cost overruns on software engineering projects, substantially reducing cost overruns (Nielsen, 1993).

Focus on the user

Human factors focuses on user requirements. Many costs associated with systems are due to unmet or unforeseen user requirements (Pressman, 1992). Human factors can work with the users to extract and refine user requirements.

Improve efficiency, reduce errors

Applying human factors principles and processes can decrease the the time to complete a tasks. At the same time, it can also decrease user errors in some cases by 25% (Galloway, 1981).

Reduce training cost

Studies have shown that incorporating human factors to create a well-designed system reduced training time by as much as 35% (Bias & Mayhew, 1994).

Increase safety

Human factors can increase safety. The application of one human factors improvement in automobiles resulted in a 54% reduction in one type of accident (Shackel & Richardson, 1991).


Bias, R.G. & Mayhew, D. J. (1994). Cost-justifying usability. San Francisco: Morgan Kaufmann.

Galloway, G. (1981). Response times to user activities in interactive man/machine systems. In Dray, S. M. The importance of designing usable systems.

Gilb, T. (1988). Principles of software engineering management. Boston, MA: Addison-Wesley.

Nielsen, J. (1993). Usability engineering. San Francisco: Morgan Kaufmann.

Pressman, R. S. (1992). Software engineering: A practitioner’s approach. New York: McGraw Hill.

Shackel, B. & Richardson, S. (1991). Human factors for informatics usability. New York: Cambridge University Press.