Introduction

Over the past few decades, the number of jobs involving data display screens and sedentary work, such as office jobs, has grown significantly. This increase has contributed to a rise in musculoskeletal disorders (MSDs) related to sedentary work. Research indicates that the prevalence of MSDs in office jobs ranges from 10% to 62%, primarily affecting the upper limbs, the neck, and the back (Gerr et al., 2002; Jensen et al., 2002; Korhonen et al., 2003; Wahlström, 2005).

Common risk factors in these jobs include repetitive finger, hand, and wrist movements, as well as uncomfortable forearm and wrist positions and high contact pressure on the wrist when using a mouse. Additionally, prolonged sitting, particularly in incorrect postures, exacerbates muscle fatigue.

ROSA, an acronym for Rapid Office Strain Assessment, is a checklist designed to evaluate common risks associated with office jobs. Applicable to positions where workers sit at a desk and operate a computer with a data display screen, ROSA assesses key workstation elements such as chairs, work surfaces, screens, keyboards, mice, and other peripherals. The method provides a measured risk assessment and estimates the need for workstation adjustments to reduce risk.

To create the ROSA method, the authors identified optimal office workstation design characteristics and ideal postures for workers to minimize ergonomic risk. These ideal characteristics stem from an analysis of the Canadian CSA Z412 guideline, which is based on the ISO 9241 standard (Ergonomic requirements for office work with visual display terminals). The ROSA method evaluates a workstation's risk level by analyzing deviations from these ideal characteristics.

 Remember...

Between 10% and 60% of office workers suffer from musculoskeletal disorders.

The most commonly affected body parts are the upper limbs, the neck, and the back.

 Remember...

ROSA stands for Rapid Office Strain Assessment.

The method is applicable to jobs where the worker remains seated in a chair, facing a desk, and operating a computer with a data display screen.

The ROSA method measures the deviation between the evaluated workstation and an ideal office workstation using scoring diagrams for each workstation element: chair, screen, keyboard, mouse, and telephone.

To apply the method, the evaluator observes the workstation while the worker performs their tasks, taking photographs or videos for further analysis as needed. Following the observation, the evaluator may conduct a brief interview with the worker to clarify any aspects of the task or workstation.

After collecting the necessary data, the evaluator scores each workstation element using the scoring diagrams. These diagrams assign a score of 1 for ideal situations, with scores increasing linearly up to 3 as the element deviates from the ideal. Specific situations related to each element can also add to the score (+1). For example, if a chair's armrest position is not adjustable, its score increases by one point. The time the worker spends using each element during the workday can further affect the score. The evaluator then calculates partial scores and the final ROSA score using the provided tables that will be shown late.

ROSA scores range from 1 to 10, with higher scores indicating greater risk for the worker. A score of 1 implies no apparent risk, while scores between 2 and 4 suggest low risk with room for improvement. Scores of 5 or higher indicate high risk. Based on the final ROSA score, the method proposes five Action Levels for the workstation, which indicate the need for action and its urgency. Action Levels range from level 0, requiring no action, to level 4, indicating urgent action is needed. Priority actions can be determined based on the partial scores for each workstation element. Table 1 shows the Action Levels according to the final ROSA score.

 Remember...

ROSA considers and evaluates 5 workstation elements: chair, screen, keyboard, mouse, and telephone.

The value of the ROSA score can range between 1 and 10, with higher scores indicating a greater risk for the person occupying the workstation. Values equal to or greater than 5 indicate that the risk level is high.

Based on the final ROSA score, the Action Level for the workstation is proposed. The Action Level determines whether action on the workstation is necessary and its urgency.

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To make data collection easier, Ergoniza provides you with this Field Sheet for the ROSA method for applying the method. Click on the image to download it.

Figure 1:

Chair scoring.

Monitor and Peripherals Scoring

Next, calculate the scores for the Monitor and Peripherals (keyboard, mouse, and telephone). Figure 2 summarizes the process for obtaining the Monitor and Peripherals Score. To do this, determine the scores for the Monitor, Telephone, Mouse, and Keyboard using the evaluation diagrams shown in the tables: Table 8, Table 9, Table 11, and Table 12.

Unlike chair scoring, monitor and peripherals scores should include the usage time score. For example, the Monitor Score consists of the score from Table 8 plus the usage time score from Table 7. The usage time score depends on the time the worker spends using the monitor during their workday. Calculate scores for the remaining elements similarly, by adding the usage time score for each element to the scores obtained from the evaluation diagrams.

Figure 2:

Monitor and Peripherals Scoring.

Final ROSA Score

After obtaining the Chair Score and the Screen and Peripherals Score, use Table E in Table 15 to determine the final ROSA Score. Figure 3 summarizes the complete ROSA Score calculation process.

Figure 3:

Application of the ROSA method.

• Gerr, F., Marcus, M., Ensor, C., Kleinbaum, D., Cohen, S., Edwards, A., Gentry, E., Ortiz, D.J., Monteilh, C., 2002. A prospective study of computer users: I. Study design and incidence of musculoskeletal symptoms and disorders. Am. J. Ind. Med. 41, pp. 221 - 235.

• Jensen, C., Finsen, L., Søgaard, K., Christensen, H., 2002. Musculoskeletal symptoms and duration of computer and mouse use. Int. J. Ind. Ergon. 30, pp.265-275.

• Korhonen, T., Ketola, R., Toivonen, R., Luukkonen, R., Häkkänen, M., Viikari- Juntura, E., 2003. Work related and individual predictors for incident neck pain among office employees working with video display units. Occup. Environ. Med. 60, pp 475 - 482.

• Sonne, M., Villalta, D., Andrews, D., 2012. Development and evaluation of an office ergonomic risk checklist: ROSA - Rapid office strain assessment. Applied Ergonomics, 43, pp. 98-108.

• Wahlström, J., 2005. Ergonomics, musculoskeletal disorders and computer work. Occup. Med. (Chic. Ill.) 55, pp. 168 - 176.

• Diego-Mas, Jose Antonio.Office workstations ergonomics evaluation using the ROSA method. Ergonautas, Universidad Politécnica de Valencia, 2023. Disponible online: https://www.ergonautas.upv.es/ergoniza/app_en/land/index.html?method=rosa