Quality Conference (2015): Human Factors Engineering on Performance and Well-Being


Presentation that me and Paul Yao, have worked with, but I will mix that with some of my positive experiences also. Paul was a guest researcher at KTH, Royal Institute of Technology last year, so we did this literature review and we created a framework. It will be published in Evaluation of Human Work in March this year I think. I should also tell you that I have a background, I’ve been working at the car manufacturer Saub instead of Volvo, I’ve been working a little bit with studies at Volvo but, unfortunately Saub is not still a car manufacturer, I’m very sorry about that. But anyhow, I still have some experience which have a lot of similarities with your Volvo experiences. What I will address today is why do we want to integrate ergonomics and quality. I will show you some brief overview of research on human performance, quality performance. And then research relationships between ergonomics and quality. I will then go into a little bit more about T2M and lean production, and I will then talk about the framework that Paul Yao and I have together proposed for integrating ergonomics and quality. And then I hope I will be able to present you on or two case studies in the field. So, from my point of view, it all started doing a study on musculoskeletal problems in chainsaw assembly in the mid 1980’s. In that study, we could see a number of different problems, ergonomic problems that the operators complained about and where they got musculoskeletal problems from. But, what we could see was also that the same tasks were really the task the quality department complained about. They were identical, the tasks where the ergonomics and the quality problem occurred. And that created my interest in the field, I started to look into the field and do some literature review, some studies and so on, and then continue with special studies in the field. So, to share with you some of the studies from literature we can see that human performance like we know is affected by a lot of work environment issues. For example by temperature, the likelihood of accidents increase with increasing or decreasing temperature, there’s an optimum where we function fairly well. And the same goes work the hand work, the dexterity, the work pace and the mental performance. Another well known figure is this one, this is productivity and as we can see, there is an optimum at a certain temperature. In this case it happens to read 25 degrees wet bulb temperature for an American adapted population but anyhow, the point is that if we decrease or increase the temperature by only a few degrees, we can lose perhaps ten percent performance with that. This is a study that is relevant to all of us here, what about the ventilation here? This was performed in schools looking at the outdoor air supply rate. So, when the supply rate was four litres per perosn and second, you could see here in the figure that the performance of school work decreased by 10% of the norm performance. But when the supply rate was increased to something around 10 eight, nine,ten, litres per second and person, the performance increases by 10% instead. So we can see here a clear relationship with outdoor air supply and performance. Illumination is of course something that is very important as we’ve heard it earlier today. And this is a collection of a number of studies, an overview of a number of studies which shows that productivity increases, with increased luminescence and that we can decrease the rejects, by increasing luminescence. So the line here, the solid line, is an attempt to integrate all these studies that these people have reviewed. I think that this is a nice view, I brought it in because the reference is from 1937 and I like that, people did good research at that time also, we tend to forget about it. And this about human performance and glare, so when you have a lot of glare, almost horizontal light coming into the eyes, you will lose perhaps 84% of your performance ability. But if you can get it from a 40 degree angle, you only lose 42% of your performance ability. Any reaction? Yes, what? It’s hard! Yes. And as ergonomists, we should all know that you should never mix blue and red. And why is that? How many can see that this slide is moving? Some of you. And, as we know, the problem here with a blue short wave light and the red long wave light, makes it difficult to accommodate for one of them because the image falls in different places on the retina, before or after the retina, in front or behind the retina. So, the eye goes like a little bit of an old projector you know that is trying to get focus from a curved slide, it goes forward and backwards, so we sometimes perceive this as a movement of the slide here. Of course, human performance is affected by noise, distraction, stress reactions and so on, accidents may change. The last slide that I will use here to give you an example of this is the human performance affected by the use of gloves. And, here we can see some motor task, fine motor task, and the baseline is the performance that you do when you do not use gloves. And what the picture shows is the increase in time, for example on the first task you can see here, the neoprene glove which is the black one, increases time with 10% in relation to working without gloves. And the bad round of PVC increases the time by about 40%. So you can see here, that there is a marked difference both between different tasks depending on what task they are, how fine motor task they are, and it differs between the quality of the gloves. So my question is then to the engineers, which one is more expensive per hour, is it the worker or the glove? And that is something that they immediately connect to. Okay, my old favourite car the Saub here. When I was working at Saub, I did a study on the relationship between quality and ergonomics. And, this was possible by being employed by the company. That means that I got access to all the data that I needed, as you and Christine pointed out. It’s very difficult for a researcher coming from the outside to get access to all these figures because they are considered secret. No car manufacturer wants to show the real quality figures. No other manufacturers either, because they don’t want to give their competitors and idea of what they’ve done and so on. In this first study we saw that the risk of quality problems was about three times higher for ergonomically problematic tasks compared to the other tasks. Another way to put that is that 40% of the quality problems were caused by ergonomic problems. We, then, in this, case, started off by, using the ergonomic problems as an input to the quality problems. So we thought that we would reverse that, so we went to Volvo’s engine assembly and started the other way around. We asked them, what are the five most important quality problems that you have, that you haven’t solved yet. And we did that in two plants, and then we had action groups working with devising actions against these quality problems. And then when we evaluated, in one plant 30% and in the other plant, 60% of the quality problems could be improved with ergonomic improvements. Unfortunately, they made a change in the quality statistics and so we couldn’t follow up to see what happened in the end, but still this is the result that we got. I can, also point out one thing about this study that has great relevance to what we are discussing here, and I say that, in this study, we can show a cause effect relationship between ergonomics and quality. And as you pointed out here earlier when you referred to this study, we could see that bad postures created fatigue or we can say discomfort, discomfort in the muscles or in the back whatever it was. And that created an quality deficiencies. And when we interviewed the assembly workers, they described it as, when you start working in the morning, you’re very fresh in your body and you perform the job really well. But it takes you one hour, or bad jobs, two hours or a little bit more when you start to feel tiredness in your muscles, you get discomfort, you get slight pain, it’s not a musculoskeletal disorder at that stage yet, but it’s starting to give them discomfort during the work day. And what they do then, is that they, they take the chance that the job that they’ve done has good quality. So what I would say is that, quality is not one off, one or zero, on and off. Because there’s a lot of subjective assessments with quality. For example, if you look at the gap between my paper and that part below here, this is the typical thing that assembly workers has to perform. A nice smooth gap, it could be a little bit larger or a little bit smaller, but it should not be angled like this. Sp for example, the hood against the body, or, the glove compartment, sorry, the glove compartment lid against the rest of the panel. And, when the assembly worker looks at it, he sees that well, it’s not perfect but I have so much pain now so I think that this will be okay. So he takes a chance and sends it away, and that’s the reason why the errors increase. And the errors, we could see it also, the errors increased during the day. So when they were fresh during the morning they perform better quality then later during a good day which is also something that we often see. So by that, I mean that we have established a cause effect relationship between bad quality and bad ergonomics. This is another study that we preformed on headlights. And they are headlights for Volvo, they are the sub manufacturer. And the work tasks were divided using the ruler method in seven categories, from a good posture to a bad posture, very good posture to very bad posture. And, the number of quality deficiencies were ten times higher for tasks with the worst working postures, according to ruler, compared to those with the best working postures. So this is in fact the highest figure we have seen here, normally we see the figure 3 that we can do, but, then I think it’s due to that, we had a fine, we had seven levels to assess the postures, and that means that we got a bigger difference between highest and lowest. We have also seen that bad visual control on assembly work and so on work, can cause bad work postures, and there are also many other researchers that have pointed out the same thing. Another area that is quite interesting when we talk about quality and ergonomics, is meat cutting. And we were inspired by a French study of meat cutting of geese. That was a study from a company who decided to decrease work pace, because they thought if they tried to increase the work pace too much, why not make the work pace rational and save money. So they decided to employ a lot of new meat cutters and decrease the work pace by 40%. And they focused very much on quality and they focused on yield for the goose liver, you know goose liver is very expensive. So, what happend was that, the meat cutters got 5 grams more goose liver per goose after this change. And that extra income was not only enough to pay the new workers that had been employed, but it also increased the profitability of the company. Another study, French study also, they decreased the work pace from 51 ducks to 42, by 18%, and the duck breast weight increased from 331 grams to 358 grams. And the ratio of highest quality increased from 75 to 95 percent. So imagine, a meat cutter has to do very precise quality movements to get out every ounce of meat to do a good quality job. And also there should be no cutting marks or cutting injuries in the duck breasts or whatever it is. In this case, they calculated the income, of the increased income to 42 cents per duck. And the costs increased, since they employed more meat cutters by six cents per duck. That means, a profit of 0.36 euros per duck, which was a lot. So in this company they also managed to increase profitability, and the musculoskeletal problems and the tiredness decreased substantially. So, meat cutters have a tough working environment, a lot of musculoskeletal disorders, a lot of cutting injuries, accidents. Over the years, the work pace has gone up, higher and higher, so the work pace is extreme high, and in a Swedish study, that is the occupation that has the highest speed of wrist movements in angular movements. I think 35 degrees per second or something like that. So it’s a very high work pace there. They have low temperatures, the branch has a low profitability, a lot of international competition in Sweden. And very few meat cutters can stay in the occupation to retire. So, we have also then in our study tried to replicate this because the Swedish meat industry say that, when we present these French studies, they say okay but that’s France, it doesn’t apply to us, we are Swedish they say. And it’s not ducks, we have beef here. So we did a study looking at the influence of work pace. We had three types, three levels of work pace. Baseline was work as usual. Then we had quality focus with lower work pace, where we emphasized the quality of the work is the most important thing. And a quantity focus with a higher work pace. And, what we could see that is the yield as you can see here in the green, decreased substantially with a higher work pace. And this is worth a lot of money, so we are about to publish a study on this one, it will soon appear we hope, not in an ergonomics journal, we will publish in meat science if they accept it. We are not sure if this is acceptable to their standards or what they are used to, but we hope so. If not, if they don’t accept it, you will see it in an ergonomics journal later on. Also, if we talk about the quality errors and the mis-cuttings and so on, you can see the blue line. We had a lot of variation so, we probably would have need a bigger study to make a smooth figures then we got, but they agree very much those two graphs here. I also want to share with you another Swedish study. It’s performed by Lena Abrahamsson in the north of Sweden in the steel works. They performed improvements to the work environment, they put substantial amount of money into that. And when they evaluated this they got, results that show that these investments have been profitable. So then they wanted to know, why did it become profitable? What was the reason for that? And, the result was that, the quality improvements were responsible for 59% of the total profit. Better productivity for 39%, and decreased personnel costs for 2%. So this is I think a very important study in the way that it shows that we must not only look into personnel costs, we must look into quality and productivity. Now I will move further into the next abstraction level I think. And talk a little bit more about quality. And, Colin you talked about how people perceived the word quality, and when we ask people in the street they say that it’s, things should be durable and they should not break, and so on. But, the quality movement, has developed quite a lot. So one of the definition that we work a lot with in Sweden is this one. The ability of a product or a service to satisfy the needs and expectations of the customer. So it’s developed into a much broader concept. And nowadays it’s also added and rather exceed these expectations because that will make people surprised, or positive to the product they’ve received. T2M as you know, points out customer focus as the most important aspect or continuous improvements, standardization, participation, process orientation. Customer focus, can according to some studies improve job satisfaction, feedback, participation and autonomy. But, too strong customer focus may then very much cause increased work load, increased stress on the employees, time pressure and reduced job satisfaction if it’s driven too far. So there’s a mixed picture of this aspect. Continuous improvements may result in many improvement of working conditions. We have seen in many international studies that there’s a relationship there. Continuous improvement when it’s applied often shows that 30% of the improvements are really ergonomic improvements, studies from the US, Japan, Germany, Sweden and so on. So here is often a good relationships improved working conditions results in quality improvements,quality improvements results in better working conditions. But if we would then move to standardization, process orientation, there is a little bit of different view here also. Some researchers said that it can result in better ergonomics, others have pointed out that it can result in only minor changes, mainly order and tidiness. Others say that it results in bureaucracy, more monotonous, repetitive and rule based tasks, that it results in stress, more time pressure and so on. And, others say that standardization is a necessary pre-condition for learning, participation and change. So the view is slightly mixed about the concept of standardization I would say. If we look at participation result in better quality, better ergonomics, according to some researchers, others point out that it contributed to better product and production quality and it improves motivation. Sometimes though, it can improve motivation soooo strongly that it can impair health, people become over committed sometimes. So that might be a risk here. What about lean production? Lean production is as you all know, an interpretation tool for the production system. I think it’s regarded as a fad now in the US, it didn’t work as well as people hoped. In Sweden it’s the most, totally most dominating change concept at the moment. When lean came around 1990, it was introduced in a number of companies and got into a very bad reputation after some 5,6,7 years, and it was not heard about for some few years. But then, there was a second wave of lean in Sweden, which for example the manufacturer Scania has been part of creating that. And that second wave of lean, to a large extent has tied lean production together with socio-technical traditions that we have in Sweden. So it’s, when I talk about lean, I mean, not mean, I mean that it’s the Scandinavian version of lean that I talk about from that point of view. The basis, is reducing resources, creating value for the customer and improving the operations continuously for example. It’s a philosophy, it has principles, it has a number of tools. You know all of this. We have collected a number, and performed a number of empirical studies of lean in Sweden. Presently we have data from 115 organizations and 9 projects, we are 17 researchers involved in this from both Stockholm and Linkoping. And the total empirical basis is from over 5000 responses from questionnaires, over 400 deep interviews, and over 400 participants in feedback seminars, in addition then, case studies, interactive research programs and longitudinal studies. So, out of that, I could talk a long time about that, but only to give you few few insights in that. Is that there is a big difference between different organizations on how they use lean on the goals, on the content, on the way they implement lean and also the context of course. We can see that the work environment improves in some organizations and it deteriorates in others. We have a program which has focused lean in manufacturing industries so out of 60 industries that we followed, we can see that a majority of the employees in the industry has improved their working conditions. But when we do it in the public sector, a majority of employees consider the opposite, it has decreased their working conditions, made it worse, made their working conditions worse. And there are also a number of important pre-conditions here, strong managerial ownership, a long term strategy, union participation, participation in union activities, and a development oriented culture. Continuous improvement and developments in the culture I would say. There are other Swedish studies and reports on lean that show, that there are some positive effects such as more influence, broader job content, higher involvement in work, job rotation, increased responsibility, team work, better work postures and less heavy lifting. But there are also negative aspects, increased workload, there’s more stress, insufficient manning, decreased cycle times, increased monotony, increased managerial control, over time and shift work. So, our conclusion to that is that lean may increase the risk for musculoskeletal problems, in particular if the focus from the companies are on savings, or on decreased resources and on using instrumental methods and tools. But we also can see that lean may decrease the rick for musculoskeletal problems if the implementations is combined with high levels of participation with problem solving, development, development orientation, improvements, continuous improvement, and also a pronounced focus on health and safety in a broad multifaceted change program. So, what is important is really the managerial strategies used in this context. Then to the framework, that Paul Yao and I have deviced. We can see that there are ergonomic concepts, quality concepts. Sometimes they are complimentary, support one another, and sometimes there are contradictions. And the framework we have proposed has a number of these pairs. The first pair that we want to look at is, total quality managements versus socio-technical systems approach. And we can see that there is a complementary area, it’s easy to integrate, T2M in the Scandinavian and perhaps the Japanese traditions with a socio-technical approach. Because the focus is on people and the processes, long term goals, emphasis on team work, participation, working conditions, cultures, values and trust. But, the more T2M has gone to the American tradition is what we say is a contradictory area it’s difficult to indicate because there can be more focus on tools, cost reductions tools, short term results, orientation and controlling the employees rather then empowering them. Of course I generalize a lot as you see now but, if we tried to make the difference clearer this is one way. The second pair that we can look at is customer focus versus the ergonomics stakeholder model. Should we emphasize the customers or should we emphasize the stakeholders, the most important stakeholders. So the complementary area would be, customer satisfaction can be achieved through employee motivation and involvement, and give consideration to all stakeholders. Then there is easy integration, but the difficult integration come if customer focus gives the highest, very strong priority to the customers in all situations And in that way gives difficult task and difficult situation for the employees. The third example that I will show is the quality policy deployment and participatory ergonomics. And we can see here that the complementary area and easy integration if participative ergonomics and and quality policy deployment and integrated, that means that we make use of employee participation. In policy deployment we make use of goal settings and encourage motivation, learning, commitment and improvement. But the opposite, difficult integration we can see if there’s no challenge to the power structures, if it focuses only on short term profit, bureaucracy, then it’s much more difficult to integrate it. Th framework still continues these pairs, quality management systems and pleb social and over social factors, process orientation versus system ergonomics, the concept of zero defects versus system ergonomics, quality value change versus ergonomic value change, continuous improvement versus participatory ergonomics and quality tools versus ergonomics principles and tools So I won’t have time to go through these but they will all be in the paper that I just talked about and the references on the last page of this presentation. The idea of using the framework is that we as ergonomists can identify the quality concept in the organization. We can find the corresponding pair and we can see is it a complementary or a contradictory relationship. If there’s a complementary relationship we can integrate and try to create a development in the organization on that basis. If there are contradictory arrangements, we can either change one of the views, the quality view we think then. Perhaps it’s possible to remove that particular quality view and change it to another or we can perhaps avoid integration totally. To give you one case study, ISO 9000 was introduced in different ways. With a developmental view which then shows the example of easy integration, or the regulatory view which shows the difficulties of integrating the two concepts. The company that used an integration way, developmental view, they started off by creating work groups that would go through their working conditions and the problem that they had, and starting a change process, something which was inspired by continuous improvement to make things work as they wanted things to work. And after that, they wrote their own instructions, they wrote the text themselves that were included in the ISO 9000. And the manager was very supportive in this way and said that the important thing is that we get a very structured way of working and good working conditions, if we get the certificate or not doesn’t matter, but the main thing is that we get the processes running smooth and well in the organization. As you see there was a lot of participation and many of the ergonomics concepts were integrated here and it worked very well in that company. The other company, one of the examples here, the manager said that the most important thing is that we get the certificate to hang on the wall so our visitors can see it. And he employed a consultant who came out and the consultant went around asked the people what they were doing and he wrote all the instructions and handed over a lot of people saying please follow this, and as we all know, that didn’t work. Them anger there wanted to use the instructions in a disciplinary way, in a regulatory way and of course it was deemed on before hand not to succeed. So this could be examples of the complementary and the contradictory ways of working with quality and ergonomics. So, to try to sum up this, which reminds me of your four hypothesis there. We can see from our research that there is a strong relationship between ergonomics and quality, we have so many studies of that. We can see that ergonomics improvement results in better quality. But we can also see that quality improvements can contribute to better work conditions if performed in the right way. And also people often say that, to be able to perform your work with good quality, that is a very important thing for your own job satisfaction. And finally, the material that I have been talking about is then in the chapter of evaluation of human work that will be out in March or possibly April this year. Thank you very much!!! We do have time before the lunch break for question and comments. Please somebody from this part of the room give me a comment. Yeah. Thank you Thank you very much for a great presentation. I truly enjoyed it you know there’s so much knowledge in there, it was amazing you know. I just wanted to get your take on the couple of slides that you had on luminescence you know, increased luminescence increases productivity and decrease rejects. So can you comment on the type of illumines because fluorescent light can cause issues because even if you have high level illumines but actually it can make some people sick and their productivity can go down in fact. Yes of course, it’s very much an over simplification only to use illumines level because light has so many other characteristics that are important for the quality of the light. It’s the reflections, the glare, the colour rendering and so on. And of course the adaption to the task, so I would day that perhaps I was a little bit hesitant to show that slide because of the over simplification of only using the luminescence level of it. But still I think it’s an argument. But when we go deeper into this issues its very important. I could give you one example that relates to some of the earlier speakers here. I think it was you Colin. We looked at the inspection of the painting of cars, of Saub cars. And we did increase the ability of the workers to detect the errors by creating a structure on the wall and then have the light that was adapted to that, so it was very see form for the workers to see the dents and to see dirt in the paint and so on. And it improved so much, so that they discovered errors on almost every car, and that was too good of results because no customers would ever detect those errors. So instead the human factor and the ergonomics approach was too effective for what they need in that case, so they had to decrease a little bit of the settings so that the inspectors only could detect the types of errors that were important for the customers. Thank you! One question or comment here please then I think we’ll break for lunch. I have a question it’s about the, you told us about how the implemented lean in Sweden was like two waves and the first wave was like Yes. They were trying to do what I guess we did in North America tool by tool, and the second times it’s like succeeding right now, it’s better. It’s better, I wouldn’t say that its succeeding because we still see a number of organizations that do it in the wrong way but the things is that we see also see a number of organizations that do it in a good way. OK but what are the prior reader for the one succeeding you know, is it because they have a socio-tech environment? Or are they trying to do it in a philosophical way, what is the success behind it you think? I think that it is that lean is interpreted in Sweden as a combination of ideas from Toyota and lean together with a socio-technical background and influence and culture that has been around in Sweden for so many years. So I think it’s a combination of these two. Okay, because here in North America we’re trying to see it as a sets of tool that we need to apply. Usually when you apply them it takes a couple of time and then you get success, but usually what happens after a couple of months it alters and success don’t follow But we’re trying to use it as tools, having tools and making them work. Don’t you think for ergonomics we could have it as a tool that we could put on beside the lean thing you know, use lean as a locomotive and have our own bandwagon as ergonomics tied up to it, and so we could have it as tools also so we can succeed in bringing the ergonomics in lean, because I know lean right now is the craze and everywhere you go people are trying to do it. If we could just have our ergonomics stuff like tools can be hooked up to the locomotive then we’re on you know, the people are gonna, what you researchers are giving us today, we could have it applied by yet. I think you have a very important point of view there. From my point of view I think that the elegance of lean is that they have so many operational ways of working and tools that can be support for the managers, and managers often say that this is much of a support for us, how to support our work, which the socio-technical tradition had not because they were on a more abstract level, so people had to as managers devise their own ways of working with it. So I think that there’s a great need fro ergonomic tools that can be used, and in Sweden for example, ergonomic value flow analysis has been developed as one of them. The other thing that I would say is that, I think that we have left the lean tool version to a large extent, in successful companies the tools are not so important, it’s more the philosopohy, the way of thinking, and the tools are used when they are needed but they are not by any means something that by themselves are important. They are not the goals. Exactly! They are means that can be used if they are needed not otherwise. Thank you! Thank you very much for that important exchange and lets pick that up discussion up again this afternoon I think, you’re going to raise a number of process level issues on how we tackle this that I think are really important worth discussing more.

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