AN INVESTIGATION OF ERGONOMIC DESIGN AND PRODUCTIVITY IMPROVEMENTS IN FOODSERVICE PRODUCTION TABLES* ABSTRACT INTRODUCTION

Transcription

1 AN INVESTIGATION OF ERGONOMIC DESIGN AND PRODUCTIVITY IMPROVEMENTS IN FOODSERVICE PRODUCTION TABLES* SUSAN J. COCCI, KARTHIK NAMASIVAYAM and PETER BORDI 1 School of Hospitality Management The Pennsylvania State University University Park, PA Accepted for Publication September 29, 2005 ABSTRACT The objective of this research was to determine if ergonomically designed worktables improve the productivity of workers in a foodservice establishment. A between-groups experimental design was adopted to collect data. Analysis of the results provided strong support to the statement that ergonomic design contributes to an improvement of about 35% in productivity in a simple, repetitive task environment. Implications for managers are discussed. INTRODUCTION The foodservice industry ranks number one in terms of work-related injuries and illnesses among various occupations in the U.S.A. Foodservice workers are particularly susceptible to various ergonomic or musculoskeletal injuries such as repetitive stress damage, lacerations and slips, trips, or falls (Atkinson 2002). The term ergonomics refers to any attempts to prevent occupational disorders and to reduce the potential for fatigue, errors or unsafe acts through the evaluation and design of facilities, environments, jobs, tasks, tools, equipment, processes and training methods (Occupational Safety and Health Administration [OSHA] 1992). Ergonomics has an important role in the foodservice industry because of the high incidence of work-related injuries. Not only is the implementation of an ergonomics program in the workplace crucial in reducing injury, it is also financially beneficial to foodservice companies. The National Academy of Sciences (NAS) (2000) noted that estimates of costs associated with reported musculoskeletal disorders is as * This article is based on a study conducted by Susan as part of her honor s thesis. 1 Corresponding author. TEL: ; FAX: ; plbjr@psu.edu

2 high as $45 to 54 billion, a figure around 0.8% of the nation s gross domestic product. OSHA estimates that an effective safety and health program can save $4 to 6 for every $1 invested (Anon 2005). Any reduction in injury rates will directly affect the firms profitability in terms of workers compensation and similar associated costs. For example, after employees at the Black Angus Restaurants participated in an ergonomics-training program, strains and sprains decreased by 30%, saving the firm an estimated $100,000 annually (Atkinson 2002). It is estimated that about 67% of the total payroll in the restaurant industry is spent on workers compensation-related costs. Thus, any savings accruing from the reduction of workplace injury will contribute to the financial health of the industry. This article presents the results of a study designed to evaluate the effects of an ergonomically designed work surface on productivity and workers repetitive stress injuries. First, relevant literature is discussed. Next, the design of the experiment used to test the hypotheses is described. Finally, the results of the study and their implications for industry are discussed. LITERATURE REVIEW The word ergonomics derives from the Greek word ergon meaning work and nomos for law. Ergonomics deals with the design of work and leisure systems, tools, procedures and practices (Helander 1997). Early work by scientists, including Ramazzini (as cited in Franco and Franco 2001) and Taylor (1911), focused on fitting the person to the work at hand. These perspectives motivated research in the selection, training and application of appropriate human skills to the job. More recently, scientists interpreted ergonomics as a tool used to adapt the job to the person. This perspective has directed attention to the adaptation and designing of jobs to suit human skills and abilities (Helander 1997). Unlike other disciplines such as anthropology, sociology or psychology which model human behavior ergonomics models human behavior in order to design systems to improve or ease such behavior. Ergonomics views the interaction between the environment, operator and machine holistically and as a system. Environmental factors (e.g., nature of task, ambient conditions) interact with human variables (e.g., competence, age) and machine characteristics (e.g., automation, other design features) to influence performance (e.g., productivity, quality). The purpose of ergonomics is to construct an optimal system designed to achieve the highest performance levels and to reduce absenteeism and medical costs (Jones 1993; Helander 1997). The impact of ergonomics on individual productivity in various settings has been documented, e.g., automobile manufacture, processed food and

3 health care. More recently, ergonomics is also making its entry into other support and service areas (Alexander and Rabourn 2001, p. xi). However, relatively few studies have investigated the effects of ergonomics in the foodservice industry. In this article, the results of a study investigating the influence of machine characteristics on productivity and individuals perceptions of pain are reported. More specifically, the relationship between the working height of kitchen tables and individuals productivity was investigated. Worktables are very common in any commercial kitchen. These are often constructed of stainless steel, and used for a variety of jobs including the preparation of vegetables (peeling, slicing, chopping) and meats (boning, filleting). The working height for kitchen tables has been normally prescribed at 34 in. However, there is no evidence that this recommendation is based on ergonomic studies (except in cases connected with the Americans with Disabilities Act). Therefore, it is not clear whether the recommended height of 34 in. is ergonomically sound for routine kitchen tasks. In a study conducted at the Cornell University, it was noted that individuals preferred electric height-adjustable workstations for routine office jobs (Anon 2005, p. 66). Research also shows that the appropriate anthropometrics of a worker should be used in designing ergonomically correct workstations (Jones 1993). More recent work suggests that most work is best done at elbow height (MacLeod 1999; International Labor Organization [ILO] 2005). Assuming that individuals have varying heights at the elbow, worktables that are a standard 34 in. from the ground may not permit a productive posture. Therefore: H1: Individuals will be more productive when the worktable height is adjusted to match individuals elbow height. While the improvement of productivity in the workplace is one aim of any ergonomically sound design, a more humane reason lies in the reduction of injuries or discomfort of the employees. The NAS (2000, p. 17) reports that about 1 million people each year report taking time away from work to treat and recover from musculoskeletal pain or loss of function due to overexertion or repetitive motion either in the low back or upper extremities. Similar to Helander s study, the NAS (2000) report suggests that workplace and individual factors interact to cause stress, impairment or disability. The aim of good ergonomic design is to reduce the systemic causes of stress or disability. Among the various factors associated with discomfort at the workplace, posture is primary. An awkward posture necessitated by workplace (including worktable) dimensions is associated with an increased risk for injury. Similarly, repetitions of a single task and job invariability are associated with ergonomic stress and injury. Other factors impacting employees sense of psychological well-being or satisfaction include work organization, job stress,

4 cognitive demands and working hours (Ergoweb 2005). Based on the discussions until now, it is argued that when work areas are designed according to ergonomic principles, individuals will experience lower levels of stress or pain. Accordingly: H2: Individuals will report lower levels of pain when working on ergonomically correct work surfaces. METHODS A two-group between-groups experimental design was adopted to collect data. The sample consisted of advanced-level undergraduate students at a prominent northeastern university who were enrolled in a foodservice management and production class that met once a week. A total of 60 students were recruited, with 30 assigned at random to the control group, while the other 30 were assigned to the experimental group. On average, the participants were 22-years old and were about 5 8 in height. The sample was almost evenly split, with women comprising 48% (or 29 of 60) of the total. The experiment consisted of the following procedures: the class instructor informed the randomly selected participants that they were assigned to a special task for that day. The assigned students were informed that they were participating in an experiment that would last for approximately 40 min. The group was then taken to a special research kitchen. The kitchen was specifically set up for the experiment. For the control group, the table height was maintained at the standard 34 in., while for the experimental group, it was adjusted based on the participant s elbow height. Following recommendations of earlier research, a uniform 4 in. between elbow height and table surface was maintained in the experimental group (Rosado 2004). Special care was taken to ensure that all other environmental parameters were held constant including lighting, noise, temperature, work equipment (such as knives and cutting boards) and floor conditions. The task assigned to the students involved the preparation of potatoes in a particular manner. The students were required to dice 70 Idaho potatoes into 0.5-in. cubes. They were provided with a sample 0.5-in. Styrofoam cube model as the standard that they were required to achieve in their task. They were required to perform the task continuously over a 40-min period. At the end of the allocated time, the diced vegetable from each individual was collected and weighed using an electronic scale accurate to the tenth of a pound. This step measured the individual s productivity. The survey also measured the participants self-reported pain on a 7-point Likert-type scale, where 0 = no pain and 6 = worst pain. This measure was used to evaluate the subjective well-being or self-reported pain from the task.

5 RESULTS The results from the statistical analyses showed that there was a significant difference in the mean production between the two groups. The experimental group cut significantly more potatoes (M = and SD = 4.96) than the control group (M = and SD = 5.09). An independent samples t-test showed that these were statistically significant differences (t =-3.31, df = 58, P 0.01). This finding supports hypothesis 1, which stated that productivity would vary based on the table height. However, no significant differences were found in self-reported pain after the task concluded between the control and experimental groups (M = 1.36 and 1.56, respectively). An independent samples t-test showed that the two groups did not statistically vary in the amount of pain they reported (t =-0.684, df = 58). Thus, hypothesis 2 was not supported. DISCUSSION AND CONCLUSIONS Drawing conclusions based on this study should be approached with caution. First, the study was conducted using a student sample. While it is appropriate to use student samples for testing theoretical constructs, the experience level in a particular task may affect the outcomes of the study. In this case, while the task was simple and straightforward, prior experience may have made some students more productive than others. However, the random assignment of students to the two conditions reduces this risk to a great extent. Second, productivity may depend on the length of time a person is required to perform a given task as well as suitable work breaks. Based on past studies showing that a 20-min working period did not provide accurate measurements of productivity (Rosado 2004), a continuous 40-min working period was chosen for this study. All participants were required to work for the 40-min period. As a result, this study did not investigate the effects of different working periods nor the effects of breaks on productivity. Finally, the singleitem measure used to evaluate pain needs more refinement. Future research should investigate pain using multi-item measures to fully capture the various facets of pain. The researchers noted based on observation that the participants in the control group were fidgeting more and voicing greater discomfort, although the statistical measures did not reflect this. This issue needs more thorough study. Despite the aforementioned limitations, the study provides strong support to the value of ergonomically designed workplaces. The study demonstrated a significant improvement in productivity in the sample population after they were asked to use ergonomically appropriate tables. This has a number of

6 implications for industry managers. First, managers should explore the use of adjustable tables to increase productivity. While earlier, workers used step stools or cutting boards to work at a more comfortable height; accidentprevention measures currently preclude such adjustments in the workplace. Adjustable tables will contribute to safe work practices. In this study, the productivity of the group working on adjustable tables improved by 34.5% over the control group. This translates into a savings of about one-third of labor costs and associated compensation and workers benefits. Second, ergonomic design suggests that work tools and surfaces should be designed with the person in mind. With the various ethnicities and age groups in the workforce, adjustable work surfaces will allow people from groups with different mean height ranges to work safely and efficiently. Finally, although there was no significant difference in the pain reported by the participants in this experiment, managers should still evaluate if improper working posture will lead to injuries and absences. As noted earlier, about one million Americans take work leaves because of musculoskeletal disorders in the upper extremities and back pains. If managers pay attention to the work practices of their employees and provide ergonomically appropriate tools, tardiness and absenteeism may be reduced. In conclusion, this study demonstrated that individuals are more productive when provided ergonomically correct work surfaces. ACKNOWLEDGMENTS The authors gratefully acknowledge the support of InterMetro Industries Corporation, without which this study will not be possible. The tables used in this study were manufactured and provided by InterMetro. REFERENCES ALEXANDER, D.C. and RABOURN, R.A Introduction. In Applied Ergonomics (D.C. Alexander and R.A. Rabourn, eds.) pp. ix xiv, Taylor & Francis, New York, NY. ANONYMOUS Variety as the spice of work. Occup. Health Saf. 74, ATKINSON, W Decreasing industry injury rates. Restaurant. Instit. 112, ERGOWEB Frequently asked questions. resources/faq/concepts.cfm (accessed June 24, 2005).

7 FRANCO, G. and FRANCO, F Bernardino Ramazzini: The father of occupational medicine. Am. J. Public Health 91, HELANDER, M The human factors profession. In Handbook of Human Factors and Ergonomics (G. Salvendy, ed.) pp. 3 16, John Wiley, New York, NY. INTERNATIONAL LABOR ORGANIZATION (ILO) Your health and safety at work. ergonomi.htm#a.%20workstation (accessed June 24, 2005). JONES, R.L., Jr Ergonomic considerations in the development of a class II, type A/B3 biological safety cabinet. Acumen (a publication of the Baker Company) 6, 1 6. MACLEOD, D The Ergonomics Kit for General Industry. CRC Lewis Press, New York, NY. NATIONAL ACADEMY OF SCIENCES (NAS) Musculoskeletal Disorders and the Workplace: Lower Back and Upper Extremities. National Academy Press, Washington, DC. OCCUPATIONAL SAFETY and HEALTH ADMINISTRATION (OSHA) Advance notice of proposed rulemaking for ergonomic safety and health management. show_document?p_table=testimonies&p_id=79 (accessed June 26, 2005). ROSADO, H.I.C Ergonomic Table Design. Unpublished undergraduate honors thesis, Pennsylvania State University, State College, PA. TAYLOR, F The Principles of Scientific Management. Harper Brothers, New York, NY.