A multi-level systems approach for the development of tools, equipment and work processes for the construction industry

Ergonomics is a key issue in the construction industry. Many work tasks and associated equipment and tools are not designed with ergonomics principles in mind. Often, in the development of power tools for construction, any attention to ergonomics is restricted to the human-machine interface and handle design. The need for ergonomics intervention in the development process originates from considerations of safety, health, physical work load, and productivity. It is argued that in each of these respects, the construction industry has lower standards than other industries and therefore has a need and opportunity for improvement. A multi-level ergonomics approach is proposed addressing these issues. The approach defines five levels of ergonomics intervention, from designing individual tools for safety, to designing wider aspects of construction and work flow for optimal productivity. This holistic approach is illustrated using case study examples of the development of power tools and work methods.     

Preventing upper limb work-related musculoskeletal disorders (UL-WMSDS): new approaches in job (re)design and current trends in standardization

In industrialized countries, upper limb work-related musculoskeletal disorders (UL-WMSDs) are the most common form of occupational diseases. They are generating a growing population of workers with reduced working capacity. The link between these pathologies and different aspects of work organization has been convincingly proven. Recent experiences in Europe supporting the combination of traditional work design methods used in manufacturing companies with ergonomics methods are reported briefly, with special focus on the use of the occupational repetitive action (OCRA) method for risk assessment and management of manual repetitive tasks. The combined approach strives to achieve the goal of maintaining a satisfactory level of productivity while respecting ergonomics criteria and, definitely, workers' health. New ergonomics standards provide for interaction between job and machinery designers and ergonomists in the design of work processes and workplaces. These standards generally refer only to the healthy adult working population and do not always provide criteria for protecting particular working populations, such as that represented by workers affected by UL-WMSDs. The results of preliminary studies concerning productive re-employment of workers with UL-WMSDs allow the introduction of some criteria for implementing current ergonomics standards in this connection. One aim of this paper is to summarize experiences of close cooperation between ergonomists, machinery designers and job designers to guarantee productivity and the prevention of musculoskeletal disorders. A second aim is to examine current ergonomics standards in the field of manual physical work (designed for healthy workers) and to suggest preliminary criteria for their implementation taking into account the capabilities and needs of specific sub-groups of the working population.     

Ergonomics contribution to chemical risks prevention: An ergotoxicological investigation of the effectiveness of coverall against plant pest risk in viticulture

The purpose of this article is to present the contribution of a trans-disciplinary approach focused on ergonomics and chemical risk control. We shall more precisely discuss how such an approach carried out in the field of agricultural work has made it possible to highlight serious shortcomings in the effectiveness of the coveralls that are supposed to protect vineyard workers from pesticides. The study results, as well as the whistle-blow that followed have questioned the control and prevention measures used until then. The aforementioned trans-disciplinary approach gathers knowledge and methods from epidemiology, industrial hygiene, occupational health and safety and ergonomics. Ergonomics were central in the development of the approach as it connected task and activity analysis with contamination measurements. Lastly, the first results that were obtained have been confirmed and reused by the AFSSET (Agence Française de Sécurité Sanitaire Environnement et Travail, the French governmental agency in charge of environmental health and occupational health and safety issues) regarding the agricultural sector but also for all other situations in which workers use coveralls as protection against chemical risks.     

High-demand jobs: age-related diversity in work ability?

High-demand jobs include 'specific' job demands that are not preventable with state of the art ergonomics knowledge and may overburden the bodily capacities, safety or health of workers. An interesting question is whether the age of the worker is an important factor in explanations of diversity in work ability in the context of high-demand jobs. In this paper, the work ability of ageing workers is addressed according to aspects of diversity in specific job demands and the research methods that are needed to shed light upon the relevant associated questions. From the international literature, a body of evidence was elicited concerning rates of chronological ageing in distinct bodily systems and functions. Intra-age-cohort differences in capacities and work ability, however, require (not yet existing) valid estimates of functional age or biological age indices for the specific populations of workers in high-demand jobs. Many studies have drawn on the highly demanding work of fire-fighters, ambulance workers, police officers, medical specialists, pilots/astronauts and submarine officers. Specific job demands in these jobs can be physical, mental or psychosocial in origin but may cause combined task-level loadings. Therefore, the assessment of single demands probably will not reveal enough relevant information about work ability in high-demand jobs and there will be a call for more integrated measures. Existing studies have used a variety of methodologies to address parts of the issue: task analyses for quantifying physical work demands, observations of psychological and physiological parameters, measures of psychosocial work demands and health complaints. Specific details about the work ability of ageing workers in high-demand jobs are scarce. In general, specific demands are more likely to overtax the capacities of older workers than those of younger workers in high-demand jobs, implying greater repercussions for health, although these effects also vary considerably within age cohorts. Functional tests for job-specific work ability should be developed for high-demand jobs in order to monitor individual functional ageing and to facilitate well-timed intervention. It is concluded that a shift from 'no-diversity thinking' to 'diversity thinking' is needed in the context of deciding about the work ability of ageing workers in high-demand jobs.     

Relationships between ergonomics and quality in assembly work

Several studies indicate a relationship between ergonomic work conditions and the quality of the work. The purpose of this study was to evaluate relationships between a number of ergonomic conditions and product quality in car assembly. The most physically demanding tasks, the tasks with the most difficult parts to assemble, and the most psychologically demanding tasks, were identified by interviews with experienced assembly workers. Information on quality deficiencies was obtained from the internal quality statistics of the company and from interviews with quality control personnel. The results showed that the quality deficiencies were three times as common for the work tasks with ergonomics problems, compared with the other tasks. An increased risk of quality deficiencies was seen for all three categories of ergonomics problems investigated. Direct causes of quality deficiencies were identified, such as discomfort from strained parts of the body, organizational factors and time pressure. The analyses pointed to certain types of task that were more likely than others to cause quality problems. The results also showed that an important factor for job satisfaction was the possibility for the workers to perform their tasks with high quality. The study therefore confirms close relationships between ergonomics and quality, and thereby points to the possibility of conducting integrated change programmes aimed at improving work quality and work conditions simultaneously.     

Impact of physical handicaps on operators of agricultural equipment

Physically handicapped farm operators and agricultural workers face barriers which make the completion of many essential farm-related tasks difficult or even impossible. These barriers are especially burdensome with respect to the operation and maintenance of agricultural equipment. This paper reports on work being done at Purdue University to assist handicapped farmers and agricultural workers who wish to continue working in spite of their disabilities. The nature of physical handicaps and proportion of farmers affected by these handicaps is discussed. Potential health and safety risks that these operators are exposed to when operating agricultural equipment are addressed. In addition, a brief overview of the Purdue project and recent activities is provided.     

Ergonomics and occupational safety and health: An ILO perspective

The ILO has a mandate to protect workers against sickness, diseases and injuries due to workplace hazards and risks including ergonomic and work organization risk factors. One of the main functions for the ILO is to develop international standards related to labour and work. ILO standards have exerted considerable influence on the laws and regulations of member States. The ILO standards take the form of international Conventions and Recommendations. ILO Conventions and Recommendations relevant to protection of workers against ergonomic risk factors at the workplace include Convention No. 127 and Recommendation No.128 which specify the international requirements concerning the manual transport of a load. To help member States in applying the ILO standards, the ILO produces practical guides and training manuals on ergonomics at work and collects and analyses national practices and laws on ergonomics at the workplace. The ILO also conducts technical cooperation activities in many countries on ergonomics to support and strengthen the capacities of its tripartite constituents in dealing with workplace ergonomic and work organization risks. The ILO’s technical cooperation activities give priorities on the promotion of voluntary, participatory and action-oriented actions to improve working conditions and work organizations of the small and medium sized enterprises. This paper reviews ILO’s policies and activities on ergonomics in relation to occupational safety and health and prescribes ILO’s considerations for its future work on ergonomics.     

Ergonomics contributions to company strategies

Managers usually associate ergonomics with occupational health and safety and related legislation, not with business performance. In many companies, these decision makers seem not to be positively motivated to apply ergonomics for reasons of improving health and safety. In order to strengthen the position of ergonomics and ergonomists in the business and management world, we discuss company strategies and business goals to which ergonomics could contribute. Conceptual models are presented and examples are given to illustrate: (1) the present situation in which ergonomics is not part of regular planning and control cycles in organizations to ensure business performance; and (2) the desired situation in which ergonomics is an integrated part of strategy formulation and implementation. In order to realize the desired situation, considerable changes must take place within the ergonomics research, education and practice community by moving from a health ergonomics paradigm to a business ergonomics paradigm, without losing the health and safety goals.     

Work-related musculoskeletal complaints: some ergonomics challenges upon the start of a new century

Three themes likely to be important within health-related ergonomics in the coming years are discussed. The first two themes concern methods for risk analysis of low-level biomechanical and psychosocial exposures. The third theme is approaches to successful implementation of ergonomics interventions. Evidence on the assessment of low-level biomechanical and psychosocial exposures by instrumented measurements is discussed. It is concluded that, despite recent advances in our understanding of exposure-effect associations under these exposure conditions, we must at present rely on more subjective methods, employed in a collaboration between expert and worker. This approach to risk analysis identifies in most cases critical exposures in a work situation. The focus should then be on the successful implementation of measures against those exposures, as identification alone does not solve problems. The aim of improved health for the workers further requires that the full complement of risk factors be considered, including work, leisure time and person-based risk factors. Finally, the need to put ergonomics intervention initiatives in an organisational context is emphasised, and examples of approaches used by Norwegian companies are presented.     

New ergonomic problems in mechanized logging operations

A Health Risk Program for forest work has been developed in order to improve health risk identification by systematic evaluation of the relationships between work and health complaints, and to create a base for decisions on different actions to reduce the health risk. This paper deals particularly with logging-machine operators and the problem of the “overload syndrome”, characterized by complaints and injuries to the neck, arms, and cervical spine. The results of health investigations of 1,174 machine operators indicate a prevailing average overload syndrome of 50%, mainly due to one-sided, repetitive, short-cycle working movements with arms and hands.

The analyses show that a whole battery of measures is needed to radically improve this serious situation. Single measures might be positive, but are not enough. To be effective, the full program of measures must be carried out and adapted individually to each machine operator. Improvements in technology/ergonomics are needed, especially regarding the sitting work posture in the cabin, i.e., design of the arms of the chair, controls, and instruments. Important factors are working techniques, micropauses, and physical fitness. New work organization is the most difficult part of the measures to realize in practice, but also the highest potential for improving the situation. Examples of issues to address in this area are design and length of the working shift, job rotation, work tasks and responsibilities, team work, and motivation and payment systems.     

Flexible workspace design and ergonomics training: impacts on the psychosocial work environment, musculoskeletal health, and work effectiveness among knowledge workers

A macroergonomics intervention consisting of flexible workspace design and ergonomics training was conducted to examine the effects on psychosocial work environment, musculoskeletal health, and work effectiveness in a computer-based office setting. Knowledge workers were assigned to one of four conditions: flexible workspace (n=121), ergonomics training (n=92), flexible workspace+ergonomics training (n=31), and a no-intervention control (n=45). Outcome measures were collected 2 months prior to the intervention and 3 and 6 months post-intervention. Overall, the study results indicated positive, significant effects on the outcome variables for the two intervention groups compared to the control group, including work-related musculoskeletal discomfort, job control, environmental satisfaction, sense of community, ergonomic climate, communication and collaboration, and business process efficiency (time and costs). However, attrition of workers in the ergonomics training condition precluded an evaluation of the effects of this intervention. This study suggests that a macroergonomics intervention is effective among knowledge workers in office settings.     

Compensation for occupational injuries and diseases: its effect upon prevention at the workplace

Abstract

In Switzerland, as in many other industrialized countries, the nature and extent of prevention at the workplace is determined, at least partially, by known cases of compensated occupational injuries and diseases. At both the national and international levels ∥ILO conventions) injuries and diseases that fit appropriate lists and definitions are eligible for compensation. It has been found, based upon an investigation of a representative sample (965 subjects) of the working population in the French-speaking region of Switzerland, that this restrictive view does not take into account the fact that a large proportion of injuries and diseases are claimed by the victims to be caused by their job. These injuries and diseases, responsible for at least one month's absence from work, are not considered to be eligible for compensation but must be covered by the patient's own insurance. Moreover, the survey showed that workers considered the ill effects on health and safety to be a consequence less of the physical working environment than of the work organization, and that this category of risks was not recognized. Thus, in addition to the reduction of hazards by the application of industrial hygiene, an informed improvement of the workplace and the work organization was required. Consequently, laws and regulations on occupational injuries and diseases should be changed in order to emphasize the role of more appropriate preventive tools, which includes ergonomics.     

Modernization of a laundry processing plant: is it really an improvement?

An ergonomics assessment was conducted in a modern, automated hospital-based laundry to investigate workers' complaints of musculoskeletal aches and pains and general fatigue. Numerous job stressors were identified requiring ergonomic solutions, including prolonged standing, excessive manual handling of transport units, non-adjustability of workstations, work pacing, awkward postures, lack of job rotation and excessive repetition of tasks. Associated health and safety issues such as noise, sharps, equipment maintenance and sanitation were also addressed. Potential mechanisms for repetitive strain injuries were substantiated and solutions for problematic areas were presented to management and the union for implementation. It was concluded that human factors must be taken into consideration when designing automated laundry systems to avoid mismatches resulting in potential injury to workers.     

Heart-rate response to forest harvesting work in the south-eastern United States during summer

Abstract

The physiological workload of forest harvesting workers during summer in the south-eastern United States was evaluated by measuring work heart-rate response. The harvesting tasks considered were chainsaw felling, cable skidding, bucking and trimming at the landing, knuckle-boom loader operation, feller-buncher operation and grapple skidding. VO₂ max of the workers ranged from 28 to 53 ml min^?1kg^?1. The WBGT ranged from 20 to 344°C during data collection. The task time-weighed, age-corrected, percent maximum heart-rate response ranged from 42-5 to 69 2°. The data indicate that the manual and semi-mechanized tasks are potentially stressful and that hotter environmental conditions increase the likelihood of higher heart-rate responses. No relationship was found between heart-rate response and three measures of static muscle strength.     

Rest break interventions in stoop labor tasks

Hand cultivation and harvest of agricultural products constitute strenuous physical tasks. Working with labor-management ergonomics committees in agricultural settings, the UC Agricultural Ergonomics Research Center (AERC) tested an experimental rest and recovery protocol for its impact on symptoms and productivity during two types of work tasks. The experimental condition consisted of adding a 5 min rest break to every working hour in which there was no other scheduled break (e.g., lunchtime). This resulted in an additional 20 min of rest per workday. We tested the intervention in two trials: Trial one compared workers (n=66) randomly assigned to an experimental or a control group during the harvest of commercial strawberries. Trial two utilized a cross-over design (n=16 pairs of workers) to compare experimental and control conditions while workers inserted bud grafts into young 18' high citrus trees. For both trials, workers under the experimental condition reported significantly less severe symptoms than workers under control conditions. The order in which the intervention was given, however, appeared to result in variations in productivity. We conclude that the introduction of frequent, brief rest breaks may improve symptoms for workers engaged in strenuous work tasks.     

Developing measures for information ergonomics in knowledge work

Information ergonomics is an evolving application domain of ergonomics focusing on the management of workload in the real-world contexts of information-intensive tasks. This study introduces a method for the evaluation of information ergonomics in knowledge work. To this end, five key dimensions of information ergonomics were identified: contextual factors of knowledge work, multitasking, interruptions at work, practices for managing information load, and perceived job control and productivity. In total, 24 measures focusing on the above dimensions were constructed. The measures include, for example, the number of fragmented work tasks per work day. The measures were preliminarily tested in two Finnish organisations, making use of empirical data gathered by interviews, electronic questionnaires and log data applications tracking work processes on personal computers. The measures are applicable to the evaluation of information ergonomics, even though individual measures vary with regard to the amount of work and time needed for data analysis.

Practitioner Summary:

The study introduces a method for the evaluation of information ergonomics in knowledge work. To this end, 24 measures were constructed and tested empirically. The measures focus on contextual factors of knowledge work, multitasking, interruptions at work, practices for managing information load, and perceived job control and productivity.     

A comparative analysis of participatory ergonomics programs in U.S. and Japan manufacturing plants

The use of a participative approach to ergonomics is growing in countries throughout the world. This paper compares and contrasts Participatory Ergonomics programs in two U.S. and two Japanese manufacturing plants. All four programs focused on the redesign of repetitive manufacturing jobs to reduce physical stress on workers. In all four cases, this traditional ergonomics concern was addressed in a non-traditional way-involving broad participation of many manufacturing functions who worked together as an ergonomics team and direct input from operators whose jobs were redesigned.

The participatory ergonomics programs were successful in making significant numbers of job changes in both countries. A comparison of the ergonomics programs across countries revealed some significant differences in structure and process. An overarching difference was in how participation was managed. In the Japan cases, participation was a carefully controlled process by which upper management and staff specialists worked through first-line supervisors to get input from workers meeting in quality (or safety) circles. In the U.S., multi-functional and multi-level task forces (including union and worker representatives) were formed and operators were invited to meetings to give input. The U.S. plants gave the task force a great deal of autonomy and virtually all decisions were group decisions. The differences suggest that effective participatory ergonomics programs can take many forms. The best program for any particular plants in differing countries depends on their own unique history, structure, and culture.     

The effect of improved workplace design on the development of work-related musculo-skeletal illnesses

An earlier paper (Westgaard and Aaras, 1984) described the work environment and the health situation of production workers at a small Norwegian factory, prior to an extensive ergonomics effort which primarily aimed to reduce static muscle strain by constructing new workplaces. It was concluded that the old work situation significantly contributed to a high level it musculo-skeletal disorders, most likely because the old work situation made it necessary to work with high level of muscle load for long periods of the working day. This second paper concerns the other important query which initiated Have the extensive ergonomics and environmental efforts at this factory had any effect in terms of improved health of the workers? The factory, the old workplaces and the ergonomics adaptations were described in the preceding paper, and are therefore not included here.     

Large-scale regional economic development: Macroergonomics in theory and practice

Ergonomics has traditionally focused on improving such indices as productivity, health and safety, and quality of work life. Such improvements are necessary to individuals and organizations, but may not be sufficient, as emphasized by the recent focus on community ergonomics and other “macrosystem” concerns. Ergonomists have begun to apply their technologies to go beyond traditional measures to impact regional economic development. A model for ergonomics in regional economic development was developed from a successful 10-year intervention in New York State. After presenting this model in terms of organizational design and core processes, two industrial cases are summarized to help validate the approach. Two large plants and industrial employers were threatened with closure. Macroergonomic assessment, research, and intervention led to significant job retention, facilities expansion, and job creation. Within 5 years, the approach was credited with several turnarounds, retaining and expanding thousands of jobs and transforming the regional economy. © 1999 John Wiley & Sons, Inc.