Ergonomics deals with how people perform work. Ergo means ‘work’ and gnomics means ‘laws of’. As a science, ergonomics identifies the physical properties of work and how the way it is done affects the body. The primary goal is to fit jobs to people, not people to jobs.
If the job and the tools used are designed in a way that is logical and minimizes wear and tear on the body, risk of injury is reduced, people will be more comfortable and productivity increases. Generally, people are also happier to come to work. At the end of the day they can go home and instead of having no energy and feeling pain, they can enjoy their home, friends and family.
Ergonomics is not limited to work. Ergonomic principles apply to what is done at home. It doesn't matter if you're at home or at work: your body reacts the same way and to the same extent: Lifting 10 pounds is lifting 10 pounds, whether it's cememt or flour.
For each person the amount of work and how it’s done overall may determine how tired he or she is at the end of the day. It also determines how much wear and tear there is on your musculoskeletal system.
Ergonomics is primarily concerned with the combined musculo-skeletal systems (biomechanics) and the nervous system which feeds and controls the muscles. There is usually little we can do about bone issues through ergonomics (exceptions may be arthritis and some other progressive conditions where impacts can be somewhat controlled).
So, we come home tired and perhaps sore. Our muscles are fatigued and stressed. Yet, the next day waits. Overnight during sleep, the body magically repairs itself. Micro-tears in muscle or tendon heal. This is a normal process in life.
Goal of the Ergonomist
An ergonomist approaches a task or job with the goal of decreasing stress on the body, and gaining control over how much repetitive strain the person is exposed to. Risk cannot be avoided. It's part of life. We can limit the micro-injuries and attempt to minmize more major injuries that can occur.
Often, only small changes are required to bring risk levels down to an acceptable level – low enough that healing sleep will be sufficient for the worker to remain healthy.
The Puzzle of Individuality
How much stress is too much stress? Unfortunately, there is no one answer. People are different. They come to a task or job with different histories, different strengths and different weaknesses – not to mention different physical sizes and capabilities.
With all these variations, the only hard truth in ergonomics is that there is no one answer. ‘It depends how tall he is’. ‘It depends how long his arm is’. ‘It depends how flexible she is’. It depends…Everything depends.
For this reason, research in ergonomics generally goes by percentages – percent of total muscle strength, percent of the population that will not fit this gadget, etc. These also provide the guidelines for manufacturing. If you’re in the shortest or tallest 5% of the population, the world is not designed for you.
The ergonomist, looking at the person who is too short or too tall, or too wide, or whose arms just don’t reach, attempts to find solutions so that they can effectively and efficiently do the job required.