Assessment of computer workstations for compliance with ergonomic guidelines: A field study

1 Introduction

As our society has moved from the industrial age to the information age many work settings have changed due to the addition of computer workstations. Computer use in the home and workplace was first introduced in the 1960s and 1970s. The US Census Bureau reported that the number of individuals working in information technology has increased from 450,000 in 1970 to 4.6 million in 2016 [1].

Workstation set up has been a focus of governmental agencies tasked with promoting safety and health in workers [2]. Anthropometrics, the study of shape and size of the human body, has been utilized in workstation design in an attempt to fit adjustable workstations to the majority of individuals [3]. Ergonomic design has attempted to minimize negative effects of workstation set up on the musculoskeletal system. Despite this focus, the prevalence of musculoskeletal disorders in office workers remains high, reportedly ranging from 20–60%in a recent Cochrane Review on ergonomics in the office setting [4].

Use of computer workstations has been identified as a risk factor for the development of musculoskeletal disorders [5]. It has been theorized that postures assumed while working at a computer result in this increased risk [6–8]. Change in the physical set up of a workstation to meet ergonomic recommendations does not necessarily result in proper use and posture by the worker [9]. As a result, worker behaviors are an additional consideration in risk mitigation for musculoskeletal disorders.

Researchers have identified a relationship between sitting posture and neck pain in a longitudinal prospective study of 1,334 workers [10]. Many individuals working in office jobs complain of low-level neck pain or discomfort (termed ‘sub-clinical neck pain’ [11]) for which they do not seek medical treatment [11, 12]. A 39%prevalence of sub-clinical neck pain has been identified in a population-based study [13]. This level of symptoms is considered to be non-interfering neck pain as described by the Bone and Joint Decade 2000–2010 Task Force on Neck Pain [14] and results in low levels of disability or pain.

A large number of studies related to ergonomics, musculoskeletal disorders and workstation set up have been published since the explosion of computer use over the past 50 years [4–10, 15–19]. In response to the concerns identified in the literature, a number of governmental agencies have developed guidelines for computer workstations. Woo et al. [19] details the timeline of development of these guidelines by 14 countries including the United States between 1972 and 1990. In this review, discrepancies were identified between the various guidelines. For example, some recommended upright spine postures during sitting, while others encourage declined or reclined positions, all based on conflicting research studies [19]. Most guidelines avoid providing specific dimensions for equipment as variations in anthropometrics of the general population make specific dimensions unrealistic.

Components of workstations that are adjustable allow modification of set up within a range provided by the manufacturers of the equipment, as seen in chairs and monitors. Other components are less easily adjustable and are marketed in standardized sizes such as a desk height of 29 inches. Making adjustments to one component of a workstation can impact the relationship of the user to other components; for example, raising the height of a chair to accommodate leg height then changes the relationship of the arms to the desktop.

In the United States, the Video Display Terminal (VDT) Workstation Checklist (Appendix) was developed by the Occupational Safety and Health Administration (OSHA) [20]. The recommendations in the checklist are not compulsory, but are considered a resource available to assist in the physical set up of an individual workstation that is safe and comfortable. A review of 16 ergonomic tools identified that the VDT Workstation Checklist was the only tool examined that was specific to the physical computer station set up for office work. [21] OSHA guidelines were selected, based on the discrepancies in ergonomic recommendations identified by Woo et al. [19] between various regions of the world for use in this study, as data for this study was collected in the United States. This tool provides a practical means of assessing a workstation leading to rapid identification of solutions. Other potential ergonomic assessment tools involve detailed measurement of forces, effort time and analysis of task, not relevant to office workstations. [21]

The VDT Workstation Checklist is completed using observational analysis of the worker and the workstation. It is an efficient method of reviewing the fit between the worker and the workstation utilizing dichotomous responses and enabling the observer to identify a problem quickly. Observational analysis has been demonstrated to be an acceptable method of workstation assessment [22]. The reliability of the VDT Workstation Checklist was reported to be moderate to good [18]. Laestadius et al. [17] utilized the VDT Workstation Checklist in a study of ergonomic intervention in a pool of over 1,000 workers. Comparing no intervention, ergonomic education and office equipment, and ergonomic intervention with the addition of individual worksite assessment, they concluded that the addition of worksite assessment resulted in significant improvement in musculoskeletal symptoms and productivity. The importance of individual workstation assessment was also acknowledged in a recent WORK publication of a model for best practice in office ergonomics [16].

Despite the attention to ergonomics, the relationship to musculoskeletal disorders, and guideline development, the degree of compliance with recommendations in the workplace is not known. Little attention has been given to the degree to which workstations are in compliance with OSHA workstation guidelines, or if they can be modified to meet these guidelines. The purpose of this study was to observe and assess computer user workstations, using the Occupational Safety and Health Administration VDT Workstation Checklist. The study also described the application of simple modifications to achieve compliance with the recommendations.

2 Methods

3 Results

Sixty workstations were assessed using the VDT Workstation Checklist. The characteristics of the subjects are noted in Table 1. Twenty-nine (48%) of workstations did not achieve a ‘pass’ score at the initial assessment, and 50 (83%) had at least 1 “no”, or item of concern. Thirty-two (53%) workstations required more than one modification. One modification was needed for 18 (30%) workstations. Ten (17%) workstations did not require any modification. A total of 121 modifications were suggested for the 50 workstations which had received a “no” on the checklist. One subject’s workstation did not comply with 12 of the 23 items on the VDT Workstation Checklist, accounting for almost 10%of the total number of recommendations.

Seventeen of the twenty-three sub-sections on the VDT Checklist were identified as needing modification in the workstations reviewed. The most frequent modifications completed included adjustments to monitor height or position on the desk, repositioning of the mouse and/or keyboard, or modification of chair settings. The absence of a wrist rest was the most frequent issue identified (43%). The suggestion was made for subjects to consider obtaining a wrist rest through an on-line resource, or the employer. Specific modifications are shown in Table 2 in descending order of frequency. All but one of the workstations achieved a pass score following modification.

Two workstations were in need of basic maintenance including a keyboard tray that needed to be lubricated so it would function correctly, and a chair back adjustment knob that was too tight. Three workstations had insufficient leg room due to equipment or boxes that the workers had stored under their desk. Removal of these obstacles enabled the workstation to be in compliance with the OSHA recommendations.

Some simple modifications were suggested for equipment that was non-adjustable, such as using books to raise a monitor or document holder to the correct height, or using pillows or towel rolls to provide better back support for chairs that were too deep. A footrest was recommended for one individual, however they were advised they could utilize a low box, or books if the cost of purchasing a footrest was prohibitive.

Some of the recommended modifications involved minimal costs. Fifty seven percent of the modifications included purchase of items including wrist rests and phone headsets. Wrist rests can be purchased for ten to twenty dollars, and phone headsets from ten to fifty dollars, although some brands can be more costly. Two individuals required new chairs. One chair was a wooden, non-adjustable chair, and her employer was able to replace it with one from a storage area. The second chair had not been adjusted for many years, and upon adjusting, the hydraulic seal ruptured. The employer noted the chair was over 15 years old, and was willing to obtain a replacement.

Eleven subjects (18.3%) preferred to work in configurations outside of OSHA recommendations, despite their workstation meeting recommended positions following suggested workstation modification. One individual preferred to work with his chair reclined, feet on the desk, and keyboard in his lap. Eight others preferred to position their keyboard or mouse further away on the desk to enable them either to rest their entire forearm on the desk, or to allow them to keep papers in the space created. Two individuals preferred having their chair higher than recommended to enable them to tuck their feet under the chair on the chair base. The majority of subjects (81.7%) appeared receptive to trying the suggested modifications.

Although not an aim of the study, during assessment of the workstations it was found that many of the office workers were unaware that their equipment was adjustable, or were unfamiliar with how adjustments were made. Some were familiar with the ability to adjust their equipment, but did not know the correct settings to use. For example, one individual had a keyboard tray which was too low, striking her thighs, so she did not utilize it. Once education was provided on how to modify this, adjustments were made, and she was able to utilize it appropriately. Another worker had armrests that were too low, and she was unaware that they could be adjusted to the correct height.

The purpose of this study was to examine the degree to which computer workstations used by office workers are compliant with current recommendations related to ergonomic fit. Almost half (48%) the workstations reviewed were not compliant, however all but one were corrected with simple modifications. This number is similar to that reported by Riccò et al. [8] who found that 53.8%of workstations reviewed, complied with International Organization for Standardization Ergonomic requirements for office work with visual display terminals.

Ten (17%) of the workstations assessed in this study fully met the 23 physical equipment settings recommended by the OSHA in the VDT Checklist. Although considered “passing”, twenty-one (35%) of the workstations had an identified concern, or a “no” check for one or two of the items. These findings were addressed with each worker in an attempt to optimize every workstation.

Subjects in this study self-identified as having sub-clinical neck symptoms, or neck pain at a low level for which they did not seek medical attention. Given the links identified between computer use and musculoskeletal symptoms including neck pain [5–8], ensuring optimal set up and use of a workstation may help to reduce these symptoms and prevent progression to a higher level. Riccò et al. [8] found that subjects with workstations which were not in compliance with guidelines were identified as having more frequent musculoskeletal complaints, with the neck the most common region. They concluded that adherence to current guidelines for workstation set up may reduce or prevent musculoskeletal symptoms in the office setting [8].

A strength of this study was the individual interaction of the researcher with the office workers at their own workstation. Though individual workstation assessments have been recommended in a best practice model for office ergonomic programs [16], the time needed to perform these assessments is not always available. The worksite visits in the current study involved an estimated time of 10–15 minutes per workstation. This is similar to the findings of Pereira et al. [22] who found an average of 21 minutes was used, which they noted is manageable for a busy workplace. Laestadius et al. [17] also provided onsite visits, but did not include details of the duration of the visits.

Employers may fear ergonomic assessment of their worksite due to concern that they could be time consuming, and recommended modifications costly. Results of this study demonstrate that most workstations can be modified to become compliant with recommended guidelines efficiently and with minimal cost. Most modifications included adjustments to existing equipment, and education of the employee on how to make these adjustments themselves.

An unanticipated finding in this study was the number of office workers who were unfamiliar with their ability to make changes to their workstations. Woo et al. [19] noted that despite the availability of adjustable office equipment, many individuals are not familiar with how to make these adjustments. This was evident in the current study, with many subjects unaware that their equipment could be adjusted. Individuals who are aware of the ability of equipment to be adjusted and how to make the adjustments still may not know the appropriate settings to utilize. Adjustments are important, as inappropriate settings of chair height, arm and backrests have been linked to office workers reporting musculoskeletal symptoms [24].

Several limitations exist in this study, including a lack of follow up with employees to determine long-term acceptance and results of recommended changes. Initial feedback was obtained following modification, however it is not known if workers returned to their original set up after their meeting with the researcher. Additionally, it was not determined whether or not employees obtained recommended equipment such as wrist rests or telephone headsets following the visit, or if they were compliant with use of that equipment. Given the number of individuals unfamiliar with the adjustability of their workstation equipment it would have been beneficial to have recorded the specific number for analysis of that information. Specific reporting of the length of time required for each workstation assessment would have been beneficial. Although employees were taught how to make the appropriate adjustments to their equipment the ability of the employee to retain this knowledge was not assessed.

Although the majority (81.7%) of subjects appeared receptive to the recommendations and changes made to their workstation, eleven subjects (18.3%) preferred workstation set-ups which are considered outside of recommended guidelines. These individual preferences were related to other priorities for the workspace such as providing more desk space for writing/papers, or being more comfortable with their feet on the chair base. Woo et al. [19] in a review of ergonomic standards worldwide notes that ergonomic design based on anthropometrics and biomechanics may not account for individual differences in comfort level and postures. Although posture, injury risk, and pain are frequently examined in ergonomic studies subject preference and comfort are not typically addressed.

The physical set up of computer workstations will continue to change due to continued advancements and modifications in computer hardware and office furniture. Laptops are increasing utilized in place of desktop computers, and roller balls and/or touch pads may be utilized in place of a standard mouse. Tablet devices may be utilized with stylus pens in a manner more similar to paper and pencil. Standing desks and treadmill desks have seen increasing popularity [25, 26]. Ongoing changes will affect the ergonomics of workstations, and will require further consideration on an individual basis. The VDT Workstation Checklist [23] has been revised to reflect some of these changes to workstations, and now includes further information for workers on varied postures including upright, declined and reclined.

5 Conclusions

Forty eight percent of 60 office workstations reviewed using the VDT Workstation Checklist were not initially in compliance with recommended guidelines. The majority of non-compliant workstations were corrected with simple modifications to the workstation. Less than 2%required significant cost (a new chair), while 57%of suggested modifications involved costs estimated at $50 or less. Though most workstations had adjustable equipment which was modified easily the majority of workers were not familiar with how to make these adjustments. Onsite visits for assessment and modification can be performed in 10–15 minutes per workstation by an individual who is knowledgeable in workplace design. Ensuring correct set up of the workstation may assist in the prevention and reduction of musculoskeletal symptoms in the workplace.

Conflict of interest

None to report.