Look at your data. What do you see? Are you confused or consumed by trying to understand how to solve sprains and strains? It is often very difficult to determine one common reason why injuries and illnesses related to ergonomic risks are occurring. This is a common frustration for safety professionals and it is because there can be many variables to the equation, and two identical injuries from the same job may have occurred for different reasons.
I have found it helpful, and necessary, to break the job up into smaller chunks and evaluate four main ergonomic risk factors in a standard and chronological way. I always separate the job tasks into distinct essential functions and evaluate each function for forceful exertion, awkward posture, static muscle loading, and repetition.
Through this process, you can match injury and illness symptoms to discrete tasks which allows you to focus change efforts in the areas where risk is high. It is beneficial to break jobs down into these discreet components when you already have a history of injury because looking at the whole job may lead you in the wrong direction by masking high risk forces and postures with repetition, which the eye has an easier time seeing. In my experience, it is always most valuable to decouple the tasks and look at minimizing high force first because they generally cause severe, acute injuries without much warning. These injuries tend to have the biggest impact on the employee’s quality of life, particularly where surgery is the end result.
Awkward postures are evaluated next because they can many times be solved by simple work station modifications without a large capital investment. Static muscle loading, which is simply the ratio of time the muscle is contracted continuously to the time of the rest period, can be minimized by job rotation schedules and job enlargement which can be determined by an industrial engineer or professional ergonomist.
Finally, repetition is considered, although many believe that repetition in and of itself generally does not cause most injuries and illnesses, rather it is an amplifier of the other risk factors. The fact is that in manufacturing environments, we are already at a disadvantage to solve this problem. Instead, engineers are pushing to make things run faster and faster! We can reduce repletion by sharing the load more, but I’ll save you the trouble, your Finance Manger isn’t going to make it easy to approve adding more people! The point of all of this is do not try to solve the entire problem all at once. It is more practical, more effective, and more accepted by your customers, to make many small changes as part of a continuous improvement change process. All you need to worry about is ensuring that you are attacking the biggest risk first, and if you break down the job into smaller bites and look at force, posture, static load and repetition in the right order, you’ll have a full plate to feast on.
Good luck and get your ergo on!
Phil Van Ess, M.S., CPE Senior Safety Manager, Sargento Foods Inc.