Health and Safety

There’s a likely chance that if you’ve been around a lab animal facility long enough, you may have heard the term “ergonomics” used in relation to some type of work occurring in your operation. If you’re a technician, the term may have been mentioned as part of an effort to resolve a problem with a particular task or work activity and if you’re a supervisor or manager, it may have been discussed in relation to some type of workplace injury. But what exactly does this term mean and why is it used so often when people talk about issues related to physical labor?

According to the Merriam-Webster dictionary,the definition of the word “ergonomics” is listed as“an applied science concerned with designing and arranging things people use so that people and things interact safely and efficiently.”Another way of thinking of it is the study of how humans interact with the “built environment” which would include such things as buildings, vehicles, equipment, and machinery, to name a few. As you would guess, there are also other names for ergonomics including “human factors engineering,” “human engineering,” and “biomechanics,” all of which relate to the same or similar studies. In it most common form, the study of ergonomics is used to analyze such things as physical stress associated with performing various types of tasks in the workplace, to either prevent an injury from occurring or address issues if one has already occurred.

When engineers perform ergonomic studies,their focus is usually on two things.The first is determining the amount of force acting on various parts of the human body whilst performing either a specific task or group of tasks,in a repetitive manner. The second consideration is the total amount of energy expended to perform this work over a given period of time. Analyzing forces on the human body involves identifying all the work elements or very specific details associated with the task(s) and then either measuring or calculating the forces and movements acting on the body from this information.The data derived from this exercise is then used in comparison with accepted standards, typically over a range of human sizes and strengths (from 5th percentile female to 95th percentile male), to determine whether a job is safe or prone to injury. This type of analysis is used to identify the likelihood of such things as repetitive motion stresses, lower back compression, arm hyperextensions, and excessive joint loading.

The second type of analysis usually performed in an ergonomic study is the determination of the total energy expended for either a specific task or group of tasks using a similar approach as that used to evaluate forces on the human body. The work elements are identified, and then the energy expended to do the job is either measured or calculated, whereby the resultant data determines the amount of energy used (commonly measured in kilocalories) by a human to perform the identified work. This exercise is done primarily to identify the likelihood for physical exhaustion and fatigue,where the data is once again compared to acceptable standards over a range of human sizes and strengths to determine if a job is safe or prone to accident or injury.

Why Bother With Ergonomics?
The short answer is money. Big money. According to a study by the Liberty Mutual Insurance Company, direct costs associated with workplace injuries amounted to $53.4 billion in 2008. This doesn’t include the indirect costs for such things as lost work hours, administrative costs,and added insurance premiums which are the direct costs multiplied by a factor of four; so the total costs for all workplace injuries in the U.S. for 2008 was somewhere around $267 billion.Can you guess what the number one workplace injury is according to their study? It’s listed as “overexertion”which includes injuries related to pushing, pulling, holding, carrying, or throwing, and is a direct result of bad ergonomics. The average amount of time off for an incident of “overexertion” is reported as fifteen days.

This is the reason why many industries have adopted the use of ergonomics as part of employee health and safety evaluations—because the costs of not doing it are far too high. Also, many industrial enterprises, such as automotive and consumer goods manufacturers, have taken a proactive approach to workplace design through the use of this methodology as they have come to realize that the upfront costs for these types of evaluations are orders of magnitude less money than taking a reactive approach to a workplace injury once it has occurred. Also, these are operations where literally hundreds of people are performing repetitive physical tasks, day in and day out in a single facility so, statistically, the likelihood for a workplace injury is much greater than other types of businesses.