NOTE: This document is provided for historical purposes only.
Tom Cook, University of Iowa, Preventive Medicine
MR SCHNEIDER: Our last speaker is Dr. Tom Cook. He is an Associate Professor for Preventative Medicine and Physical Therapy at the University of Iowa, where he serves as Director of the Biomechanics and Ergonomics Facility within the Injury Prevention Research Center. He is a physical therapist and has a doctorate in industrial engineering, specializing in ergonomics.
He has authored or co-authored over 50 scientific papers, chapters and books and served as an ergonomics consultant to numerous companies, labor unions and government agencies in the U.S. and Canada.
He has also been working with us for several years on our ergonomics project and specifically he has been working with an operating engineers contractor in Iowa City. He is going to talk about some of the problems and some of the solutions for operating engineers for ergonomic problems.
DR. COOK: Thank you, Scott.
One of the advantages or disadvantages of being the last speaker is that I have been sitting as long as you have been sitting. So I would say I will give you ten seconds of my time for everybody to stand up and stretch a little bit, including our speakers, of course.
My topic is operating engineers, and I, at the outset, would like to recognize my colleague, Chris Zimmermann, in the audience, who really did most of the work here. I just have to talk about it.
In the ten minutes I have been allocated, I would like to break it up into two pieces. First is a little bit about a survey that has been alluded to before, a symptom and job factor survey, that we have done with about 3,000 or so construction workers, including several hundred operating engineers.
We have used that as a basis for trying to identify where the problems are. One of the first things we heard this morning is you have to know where the problems are before you try to fix them. So I have used that as a tool to help identify, by trade, some of the aches and pains and what we call trade-specific injury or complaint profiles.
Then I would like to show you 10 or 11 fairly simple modifications that we have come across. We have been directed to them by the operating engineers we have worked with as equipment modifications that they value. The particular contractor that Scott mentioned, when we asked these operating engineers, was who was a model person they would like to work for, invariably they all identified the same contractor. So we went to find out what it is he is doing that everybody liked so much.
First a little bit about the survey. As I mentioned, we are interested in getting some direction as to where to look for ergonomic best practices. It is a self-reported survey that we copied primarily from the Scandinavians. A body diagram that says, "Where do you hurt?" "Where in the last 12 months have you had a work-related ache or pain?" "Have any of those aches or pains caused you to lose work?" "Have any of those aches or pains caused you to visit a physician?" So some measure of severity of the aches and pains.
We also have a listing of 15 job factors, things like working overhead, handling small objects, hot, humid conditions, standard questions or job factors that we have been asking not only construction workers but several thousand other manufacturing workers to try to get the workers' perceptions of what are the problems within their particular jobs.
Just briefly about the method: self-administered. We got the union folks to endorse sending the questionnaires back to us. We sent them a reminder postcard a week later. If they sent their survey back, they were entered in a raffle for $100 cash prize. That seemed to be a big one.
We couldn't follow up on the people who didn't respond because we couldn't get to the mailing address list of the union. They kept that confidential. And we actually did the survey the last week in December.
About 38 percent of the operating unit engineers sent their responses back to us. That amounted to 410. In our other 12 construction periods we surveyed, we got about the similar, 36 percent of the ones that we sent out.
The union folks tell us that's terrific. They are lucky if they get 20 percent back on any survey they send out to their own membership. It must have been the $100 prize that did it.
Our respondents were on average about 46 years old. They had worked as an operating engineer for about 20-some years. About a fifth of them had apprenticeship training. About three-fourths of them were working at the time of the survey, and they reported that they worked on average about 42 hours a week. So these were people who work for a living, as opposed to some of the rest of us academics, I guess.
About 10 percent of our respondents didn't use any kind of equipment, these were the mechanics or the foremen. So about 90 percent of the people who responded actually operate equipment. On average they reported operating about three and a half different kinds of equipment. One of the things that we learned, certainly, is that operating engineers --the work involved in being an operating engineer is not the same. It very much depends on the type of equipment that you use.
This is an example of our complaint profiles here. What it says on the left-hand column is anatomic region, and then it is percentages of those who said they had a job-related ache or pain in that region in the last 12 months, percent who missed work or reported missing work, and a percentage that said they had seen a physician.
The areas that I have highlighted in yellow are the areas that were above the average for the other construction trades. All the other blocks there were below average compared -- now again, we are comparing people to carpenters, electricians, plumbers and other people who do some heavy-duty work. But compared to those people, only neck and ankle/foot was above the average for that other group.
You will see low back was still quite high, as it was in all the trades. That was the prize winner for all the trades we studied. But this told us that if we are going to make some ergonomic interventions, we probably ought to be looking at things that affect neck and foot/ankle as the top priority, the foot/ankle surprised us at first. The last thing I thought was that someone sitting operating a bulldozer or a crane, would have troubles with were their feet or their ankles, or really high up there as well are knees.
If we looked at the problematic job factors and asked them what they perceived to be problems with their work, they said working in the same position for long periods was a problem. The mean score on a scale of zero to 10 was 4.65. Their peers in the other construction trades was 5.87. You see again that compared to the other construction workers, this group of operating engineers rated these job factors slightly lower. It doesn't mean they don't have problems, but relative to the other groups they seem to be lower. These were the five most commonly reported problematic job factors.
Many of the construction workers, the hot, humid, wet conditions is a little higher than what it was ranked by the operating -- again, it was a little surprise.
Three factors, though, I will talk about very briefly that we think we found out from the survey. Operating engineers, we split them into groups: those who worked as an operating engineer more than five years; and those who have worked less than five years, just as a general cutoff for experience.
We found that there were increased complaints and missed work and physician visits in the people who had worked more than five years. That is not true in some of the trades, because there is a survivor effect. If you make it five years in some trades, you may be all right for the next 15 or 20 years. The other people have dropped out. The people who have hurt themselves in the first few years are gone.
We saw the reverse effect here with operating engineers. There were more complaints among the old-timers, if you will, who have been around awhile. Also increased problematic job factors were reported by the more experienced operators.
In terms of type of equipment, we broke it down. We had enough numbers for five different types of equipment, and there isn't time to go into each one. But we found that definitely the complaints, the missed work and the physician visits had different patterns for five different types of equipment we studied. For example, backhoes, bulldozer operators, crane operators, and so on.
Our problematic job factors were also somewhat equipment specific, different complaints depending upon the type of equipment primarily used.
The third factor that I will discuss briefly here is the effects of equipment age. The feedback we received from many of the operators is the new equipment is much, much better. And indeed, when we broke it down by age, the equipment that is newer than five years or older than five years -- the newer than five year equipment, we had the same pattern of complaints in terms of where they hurt, but decreased reporting in terms of missed work and physician visits. They had the same aches and pains, but they didn't seem to result in as much lost work or as many visits to a physician.
We also saw decreased reporting of problematic job factors. Basically they were happier. They complained a little less.
What we found then, as compared to other construction trades, was that musculoskeletal complaints in operating engineers were less prevalent except for neck and foot/ankle, and that the problematic job factors were also less prevalent, or they had fewer complaints.
But among operating engineers, there were influences of the type of equipment they used, how long they had been on the job and whether or not they operated some of the newer equipment.
As I mentioned, we talked to some of these folks in smaller groups and asked, "You know what's going on with this foot/ankle business and this neck business and this low back business?" They pointed to this one particular contractor. I will show you eight or ten examples of small things that he did to his equipment that the operators found very desirable.
In fact, some of the local equipment suppliers said that other contractors would come in and say, "Fix my equipment like you fixed his." So everyone, not only the workers but the competitors, knew that this person had made some equipment modifications that were beneficial both in terms of aches and pains and financially.
This contractor, again as an example, did some things -- you don't see real well here because it is painted yellow like everything else, but there is an additional step that this contractor has his people weld onto the different pieces of equipment.
When we started asking about the foot/ankle problems, we found that many of the foot/ankle problems are acute injuries that resulted from getting in and out of the equipment. You know, they climb over slippery treads on bulldozers. There is no easy way to get in and out. They sit in this equipment for four, five, six hours and then get up and have to jump down onto uneven surfaces. So getting in and getting out seemed to be a major problem. If we looked at the workers' compensation data and medical claims, getting in and out was reported as related to the foot and ankle problems.
So this contractor puts extra steps on his equipment. Again the arrows point to additional grab bars that he puts on. He takes a brand new piece of equipment that might cost $130,000 and welds extra handrails on it so his people can get in and out without hurting themselves.
He also isn't satisfied with the anti-slip surfaces that are put on around the cab areas. There is a closeup on the left and a shot on the right as to where it is. He has his own, or buys his own, higher grade anti-slip surfaces; and again, puts those on the new equipment that he buys.
He has about 330 pieces of dirt moving equipment, this particular contractor. He also installs additional mirrors. This is a large backhoe, and one of the problems is the neck problem related to looking around behind them all the time as they use the backhoe. He simply installs extra mirrors to limit the amount of required twisting.
Another thing he does is to take the old cable scrappers here and replace them at a cost of $20,000 to $30,000 apiece with hydraulic controls so that the operators don't have to keep their hand in the air and constantly tug on this lever that controls the cables that controls the scrapper that digs the dirt. He is willing to invest that because he is convinced that it limits the problems that he has on the musculoskeletal side.
And wherever feasible or possible he changes manual cable controls and lever controls to joy stick controls. This is a costly investment that he is willing to make. You see three pictures of different joy stick controls here.
He is also very aggressive at seat replacement. One of the complaints we received from many of the workers who work for other contractors is the seats break, the suspension system goes bad, but they still have to sit on this thing and bounce around on rough surfaces all day anyhow. He has three extra seats sitting in his shop all the time. As soon as a worker complains that a seat doesn't function well anymore, it is replaced with no questions asked. That's pretty much up to the operator's discretion to request that.
Also, one of the things he does on his dozers here that he uses to pull these big scrappers, is to put several thousand pounds of additional weight to keep the nose of the tractor down to pull level and get more tread on the ground. It also provides a much smoother ride for the operator. So there is a 3,000 pound nose weight there in that one arrow and several thousand pounds of additional weight that he puts on.
He also has a very aggressive glass replacement program. He has a maintenance truck that goes around to his sites, and whenever there is a report of busted glass, it is replaced. He doesn't want his operators stretching and reaching to look around the cracks in the glass to see what they are doing, and obviously there are safety hazards associated with that.
He also takes on his scrappers and moves all the grease fittings, connects them by tube down to where you see the white arrow here, so that his maintenance people can stand on the ground and grease the fittings on the scrappers rather than have to climb up on top of them. He has found they get greased more frequently if the worker isn't at risk climbing up with his muddy shoes or whatever on top of a scraper to lubricate it.
He retrofits many of these older style bulldozers with a smaller rollover protection structure, he has actually made his own measurements and found that the sound levels are about half of what they are on the original rollover protection structure that came with the piece of equipment.
These are some examples of things I would say are not rocket science. They are straightforward responses to workers input about things that would make their job more injury free, more comfortable. The bottom line is that his operators are willing to work overtime because they are more comfortable and they are not wiped out, they actually are more productive than a lot of the competition. This particular contractor continues to be very successful and gets a larger and larger part of the market in his area.
Thank you.
