Ergonomics done right.®
September 18th, 2012

Webinar Q&A: Six Ways to Leverage Technology in Ergonomics

By Jeff Sanford, CPE and Kent Hatcher, CPE

Thank you to those of you who attended our live webinar last week on leveraging technology in the ergonomics process. We received a lot of great questions and our answers are below. For those of you who could not attend, the recording will be posted to our archived webinars page by next week.

Q: ­With the ADA laws, can you deny someone a job based on a pre-employment screen? or will you have to find reasonable accommodations?­

A: We are not experts in ADA Laws and as such are not able to answer this question directly.  But in relation to the topic of today’s discussion, you can use the data collection equipment discussed to determine the elements of the pre-employment screen.   For example, if one of the job requirements is insertion of a clip you can use a digital force gauge to record the exact force required and use that in the pre-employment screen.  The same can be done for efforts to push carts, assemble two parts together, etc.

Q: ­ErgoPak gives you force data over time. If you were measuring the force needed to press a button, how would you analyze the data, i.e., do you use the average, the peak or do you filter and clip the data? ­

A: In this case you would use the peak, as this would represent the worst case scenario and is the single point in the action we are most concerned with.  Just be careful that you don’t ‘bottom out’ when you take the measurement. This occurs when the force gauge records the effort after completion of the action when the gauge may jump or the assessor pushes excessively. This results in a spike in the data and can skew your findings. A slow and steady action to completion is the best method.

Q: ­Can you please add a little more explanation on the device presented before the Accelerometer?­

A: Electromyography is a way to measure electrical activity of muscle.  The muscle basically sends out signals when they’re activated and EMG can measure it. So the higher the frequency of activity measured the more recruitment and the higher you’re working. So what the technician will do is take a Max Voluntary Contraction (MVC) for a specific muscle for a certain person, measure activity during a task and then figure out what percentage of their max they’re working at for the task.  So you can see if someone is working harder for a certain task or at what percent of max.  If muscle activity is over 20% of max for an 8-hour task that would be considered high.

For industrial applications, you can buy systems now that are considered “portable” but these require a lot of training to do this properly and it’s not very effective or user friendly if done during a job.   It’s better in a controlled environment where you mock up a task.  If you put a sensor on the arm you can get cross-talk between muscles and this will significantly skew your data (you’re basically measuring the wrong thing).  Most important when using EMG, is knowing what muscles you should even be measuring for the task.

Q: ­Where is the HTLiftCalc (NIOSH) app?

A: Here’s a link to the NIOSH app.

Q: ­Have you heard of SANTOS, a human computer model from the University of Iowa and, if so, what is your opinion?­

A: SANTOS is a relatively new product and we have not used the software directly.   Below is an excerpt from their website (along with the link) introducing the product:

Santos Human Inc. is the for profit company licensed to distribute the world’s first virtual human computer model and application able to accurately predict human motion. All of the research and development for this application arose from the research at the College of Engineering’s Center for Computer Aided Design Virtual Soldier Research program at the University of Iowa. Funded primarily by the US Army, we conduct basic and applied research for creating new technologies dealing with human modeling and simulation. The objective is to create human-like life on the computer, virtual humans and soldiers that can walk, behave, and talk like we do, yet are able to answer questions in the virtual world. We allow the virtual soldier to experience the product in the virtual world and provide the user with feedback. Our group is one of the largest groups conducting this type of multidisciplinary research consisting of faculty, professional staff, scientists, engineers, clinical researchers, and graduate students who have come together to create this new technology. Our virtual human modeling and simulation environment is called Santos™.

Q: ­Do you recommend a stretch program? use eggsosizers, stretch bands, rollers?­

A: We do not consider stretching to be associated with ergonomics.  Stretching can be an element of a musculoskeletal disorder reduction plan, but it should not be considered ergonomics.  Ergonomics is an engineering discipline focusing on physically changing the workplace to reduce the risk of injury.

Q: ­Do you provide e-learning /online assessments in office ergonomics?­

A:  Yes, we have an e-learning module in our online office ergonomics solution called Ergopoint Office Suite.   More information can be found at

Q: ­How much is the RPM system from Humantech?­

A: We can provide pricing specific to your organization’s needs (site and corporate licenses are available).   Please contact one of our consultants to discuss further.

Q: ­Are there specific system requirements for RPM?­

A: RPM is a web-based program that runs on most internet browsers after IE6.

Q: ­Are there any standards that govern vibration for VDT displays? Working with a client that has a LCD screen mounted to a tool that vibrates and people are complaining (motion/sea sickness).­

A: We are not aware of a specific standard for exposure to a vibrating VDT.  However, stability of the image is important for comfort of the viewer.  The image should be stable, free of flicker and jitter.