Learn how to develop your “ergo eye” and recognize ergonomic risk factors in your workplace.

Video transcript:

Hey, everyone. This is Mark Middlesworth of ErgoPlus. And today, my goal in this video is to help you develop a sharp eye, an ergonomic eye if you will, for identifying risk factors, ergonomic risk factors, in your workplace. If you’ve followed us on our website or on our blog or the prevention school, if you’ve read our e-book on a better approach to musculoskeletal health, you already know, but I want to review that we believe MSD prevention is a shared responsibility. We believe there are risk factors on the ergo side, on the company side, workplace risk factors that lead to excessive fatigue and discomfort. And that can turn into an injury over time, especially when in combination with individual risk factors that the individual is in control of.

So certainly, we want to reduce MSD risk factors by proactively engaging workers in the injury prevention principles that they can employ to use proper work methods, proper body mechanics. We want them to be aware of ergonomic issues in the workplace as well. We want them to be educated and motivated to use pre-shift warm up stretching programs and other recovery tools for fatigue, so that that fatigue doesn’t turn into discomfort, pain, and eventually a musculoskeletal disorder or injury.

Having said that, the focus of today’s video is on the workplace ergonomics side, and we’re going to be talking about screening risk assessment for the primary ergonomic risk factors. The three primary ergonomic risk factors that we see in the workplace are awkward postures, excessive forces or high exertion, and high task repetition. And so let’s tackle those one at a time.

Awkward Posture

Awkward posture equals high risk. When joints are worked and moved outside of the mid range of that joint outside of a neutral or semi-neutral position, then the risk of developing an MSD can certainly increase. Awkward postures place excessive forces on the joints, overload the muscles and tendons around the effected joint, and certainly increase risk.

High Force Exertions

High force exertions also significantly increase the risk of employees developing an MSD. Many work tasks can require high force loads on the human body. That’s certainly true of many workplaces. Muscle effort increases in response to high force requirements, and that increases the associated fatigue which can lead to an MSD. So MSDs typically arise as a result of a combination of things but certainly high force exertions being one of the primary risk factors that leads to muscle fatigue. Muscles burn fuel to do work, right? And the result of burning that fuel is [inaudible 00:03:53] metabolic waste and byproducts that accumulate in those muscles, creating fatigue in the muscle tendon units. And if that is not alleviated or relieved, if that lactic acid accumulation is not flushed out of there adequately with repair, then that can certainly cause an increased risk to developing an MSD.

High Task Repetition

High task repetition certainly is a part of it, typically when coupled with awkward postures and excessive forces. Repetition in and of itself, typically not. The body is made for movement, right? So typically not going to cause an issue unless there’s also an accompanying high exertion or awkward posture associated with that repetitive motion.

So in order to help you develop a good ergonomic eye, let’s talk about postural risk factors and kind of start at the head and neck and work our way down through the body, okay? So here’s a good question to ask when you’re conducting a walkthrough or trying to do an initial screening assessment of a job and looking at ergonomic risk factors, do employees perform tasks that require repetitive or sustained awkward postures for prolonged periods of time, so greater than two hours in a shift? Are they exposed to those tasks that require awkward postures?

So for the head and neck, we’re looking for sustained neck extension or repetitive neck extension or hyperextension. This can be caused by a visual obstruction or a visual display that’s just way too high. So neck extension is something that we want to look for. Neck flexion, sustained forward flexion of the neck and this is certainly more common in the workplace as workers are assembling or manufacturing something typically at about waist level and have sustained forward head positions. If these forward positions are extreme, if there’s a physical obstruction that creates a requirement for forward head, then that can certainly increased risk significantly.

If there is side bending required because of a visual requirement, we have to see something, and we can’t see it, there’s an obstruction there, so we have to bend our head to the side, if that’s sustained for a long period of time, and that’s done throughout the course of the work shift in prolonged fashion over a couple of hours a day, then that can create a problem as well. Certainly neck twisting is another issue that can be caused typically by a physical or a visual obstruction. So take a look at the head and neck, observe the worker performing a couple of cycles, ask the worker, interview the worker to see if there are any impacts on the head and neck, any awkward postures that are required by the job.

For the shoulders, we’re looking for, again, away from neutral positioning, either repetitive or sustained, and we’re typically looking at high and far reach, significant flexion or a extension of the shoulder. So significant flexion would be, if this is arm to the side neutral, you’ve got about 45 degrees of flexion here, 90 degrees here. So above 45 degrees is getting into a danger zone and certainly above 90 degrees of flexion or abduction. Abduction is elbow out. So flexion is forward. Abduction is elbow out away from the midline of the body. Greater than 45 degrees starts to be a caution zone area, and certainly above 90 degrees of either flexion or abduction is significant ergonomic risk.

So we’re looking for tasks that require high and far reach, excessive forward flexion of the shoulder, height extension or hyperextension of the shoulder, abduction or elbow out away from the body, or also internal and external rotations. If those are forceful and repetitive, that can certainly lead to shoulder fatigue, discomfort, and pain that could lead to an MSD.

For the lower back, this is fairly straight forward. Everybody’s aware, I think, I hope, that forward and side bending of the low back can create awkward postures and increased risk. Squatting, twisting, arching, or hyperextension of the back is less common but is a risk factor if that is present in your workplace. Prolonged sitting in combination with forward bending, side bending, or twisting certainly increases the risk to a low back MSD.

For the upper extremities, we’re looking at tasks that require forceful exertions in awkward postures. So outside of a neutral position for the wrist is ulnar deviation. A tool or design flaw can potentially create a situation where there’s excessive flexion extension or wrist deviation. So you’re looking at significant forward flexion, and if that’s in combination with ulnar deviation, that can certainly be an increased risk for an MSD. Excessive gripping and wide gripping is an awkward posture that we would want to pay attention to as well.

For the lower extremities, foot pedal use greater than two hours, sustained or highly repetitive, can certainly cause problems for the lower extremities as well as up the kinetic chain up into the back and hips as well. Rotation of the lower extremities, so if there’s an obstruction for the toes or the forefoot, and the worker is having to rotate externally, rotate the foot outward, then that can lead to lower extremity musculoskeletal issues. Certainly kneeling, crawling, deep squatting are also risk factors that you would want to identify as well for the lower extremities.

In terms of force, the question that we want to ask is, do employees perform tasks that require significant physical exertions? Okay, so in terms of lifting exertions, we would want to look at lifting or lowering of any heavy object that weighs greater than 51 pounds. So in addition, frequent lifting or lowering of loads weighing 25 pounds or more out of the power zone basically, so above shoulders, below knee level, or away from the body, would indicate that that lifting task should be evaluated further and typically, with the NIOSH Lifting Equation Calculator. And we’ll talk a little bit more about that in a minute, or the WISHA Lifting Calculator. If you’ve got a lift or lowering task that is over 51 pounds, if you have any of those at all, they should all be assessed using one of those lifting calculators. Or if there’s frequent lifting of loads weighing above 25 pounds out of the power zone, above the shoulder, below the knee, away from the body, then you would want to further assess those tasks as well, taking a look at all of the task variables involved, not just weight but horizontal location, vertical location, coupling, and all those types of things that are addressed in the NIOSH Lifting Equation Calculator, okay?

So other excessive forces with respect to pushing, pulling, and carrying, you want to try to identify those for further evaluation. If there’s any high exertion, pushing or pulling, that requires a significant change in body mechanics, so you’ll see workers that are clearly under some stress to push and pull things around or to carry objects, heavy objects for short distances or long distances can be an issue, and if any of these are identified, we would recommend using the Liberty Mutual or the Snook Table Calculator to, again, determine all of the variables involved, the initial force requirement, the sustained force requirement to push or pull a load. And in terms of carrying, the Snook Tables offers a calculator as well considering the variables of weight and the distance carried.

Hand-arm Vibration

Hand-arm vibration and exertions can be an issue, so you would want to flag any tasks that requires sustained or forceful gripping or pinching to be further evaluated. If there are high impact or power tools that the worker is exposed to for a significant portion of their day, then we would want take a look at the total vibration exposure and use the Hand-Arm Vibration Calculator assessment tool to make sure that the total exposure to those tools does not exceed acceptable ergonomic limits.

Excessive Force Loads

Are there other exertions and tasks that require substantial force loads resulting in changed facial expressions by the worker or changed body mechanics as they attempt to perform that task? I’ll look at their expressions, especially their facial expressions and their body mechanics, and even get an idea from an interview or from doing the task yourself what the force level exertions are. And if they are excessive, we would certainly want to take a further look at that.

Compression

Compression forces, hand tool compression forces over soft tissues, and this one in particular right over the median nerve in the palm of the hand can certainly increase risk of a neurological issue, restriction of blood flow, and contact stress on the median nerve. So we would want to certainly flag that for further evaluation and ergonomic improvement as well. So any kind of soft tissue compression contact stress on the forearm or the upper extremities can be a significant ergonomic risk factor as well as impact stress that can result from using big heavy power tools or hammering on products for whatever reason.

Repetitive Tasks

And then repetition, we want to know what the exertion frequency is for the neck, shoulder, forearm, low back, and lower extremities. We would look at a repetition rate of about four reps per minute or sustained exertions that are for greater than five seconds. For the wrist and hand, we up that just a little bit. So you’re looking at repetition rates of about 15 repetitions per minute or again, sustained tasks, pinching, power gripping greater than five seconds. If it’s any kind of forceful exertion of pinching and gripping, we would want to flag that for further assessment.

Ergonomic Assessment Tools

So we have a number of ergonomic assessment tools and guides that we’re happy to share with you. We’ll be doing more videos like this, but I want to call your attention to several calculators and step-by-step guides that we have on the key ergonomic assessment tools that we recommend for further evaluation if your initial ergo eye screening of a job raises some red flags. So we highly recommend the NIOSH Lifting Equation Calculator for lifting tasks greater than 51 pounds or greater than 25 pounds if it’s frequent or outside of the power zone. The WISHA Lifting Calculator is another great tool for evaluating manual material handling tasks. It’s a little less detailed than the NIOSH Lifting Equation Calculator, but nevertheless, a solid objective tool that gives you, as an output, a recommended weight limit given the task variables involved.

We already mentioned the Liberty Mutual Snook Tables and associated calculators. We have a calculator available for you to use to evaluate pushing tasks, pulling tasks, and carrying task, also has lifting component as well. And then the Rapid Upper Limb Assessment (RULA) and the Rapid Entire Body Assessment (REBA) are great ergonomic assessment tools as well that give you a risk level score. The RULA is the Rapid Upper Limb Assessment and the REBA is the Rapid Entire Body Assessment. We’ve developed calculators for both of those assessment tools and happy to share those with you. How do you do that? Check out the ErgoPlus Platform. You can go to ergo-plus.com/platform and create a free account and check out all the assessment tools that we have.

All right. I hope that helped you in some way to develop a better ergonomic eye. We need to have a sharp eye to identify ergonomic risk factors in the workplace that we can further assess objectively to determine whether or not they exceed recommended ergonomic guidelines. Hope you have a great day, and we’ll talk again soon. And remember, think prevention.

Manage ergonomics in less time and with less hassle with ErgoPlus Industrial.

Schedule a demo