International Journal of Industrial Ergonomics, 8 (1991) 195-196 195 Elsevier

Preface

Construction is a major industry in the eco- nomics of all countries, taking a varying but a significant share. For the United States, a figure of 10% to 15% of the GNP has been commonly accepted. Unfortunately, research endeavors in the general area of construction are not com- mensurate with the size of the industry. Given the impact on the overall economy it can produce, the lack of such an endeavor is glaring. It has been estimated that the cost of construction accidents may be as much as 1% of the GNP. The construc- tion industry unfortunately does not allocate its resources for research and development com- mensurate with its volume of activity. It is known to spend only one tenth of the proportion the manufacturing industry spends on research and development. Even the most significant develop- ments and inventions in the construction industry have not resulted from direct funding by the in- dustry itself. Whether it is due to constantly changing personnel and projects or other factors is hard to say. Furthermore, construction from the very outset, due to the nature of the job and activities, is considered hard and rough work with inherent hazards. The workers, therefore, not only accept the risks but also know the temporary nature of the job.

A lack of stability and rapid labour turnover may create a sense of less responsibility toward the workers by employers. The workers may, in addition, derive their job satisfaction from seeing the outcome of their work - house, building, road, bridge or whatever else. Since this complex inter- action of the intrinsic factors is unlikely to change, it is hard to project as to how the challenges and issues or ergonomics in construction will be ad- dressed. The nature of construction work is very varied. Indeed, the records of one construction company revealed 146 different trades working for it, most of these being significantly different from all others, and requiring different ergonomic con- siderations. Addressing all relevant issues will be a

tall order. However, this special issue explores some aspects.

The tripartite goal of ergonomics of (a) optimis- ing comfort of workers, (b) ensuring safety of workers, and (c) enhancing productivity of the work is as relevant to construction as to any other industry. However, their implementation in con- struction poses challenges which are unique. Many of these factors are addressed in this issue directly and indirectly with respect to some selected oper- ations in the industry. The issue begins with con- sideration of the injury profile of the construction industry in Alberta in the Canadian context, and a case study on the effects of a non-monetary motivational factor in reducing work injury. Though the statistics presented are derived from Alberta and Canada, it is suggested that it may be just as relevant to other parts of the world. It is obvious from the statistics presented that safety is a major problem in construction. Injuries are pre- cipitated by accidents as well as overexertion. Considerable room for improvement appears to be available through ergonomic interventions. He- lander pursues these issues looking into some of the specific job categories with their hazards. He has also looked in greater depth at factors such as falls, other common external factors, excavation, machines, hand tools and back injuries. The costs associated with the construction injuries in terms of workers' compensation is considered as an in- centive to employers to prevent losses.

Ortengren et al. present a study in which the load on the muscles in manual and powered screwdriving is estimated electromyographically in different posture of tasks. The~e kinds of tasks are frequently employed in electrical installation as well as many other construction jobs. The next three papers deal with bricklaying. Luttmann et al. have performed electromyographic analysis of the task of bricklaying at different wall heights. Jorgensen et al. have studied the development of fatigue in the lumbar paravertebral muscles of

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196 Preface

bricklayers during the working day. They looked at isometric endurance, strength and spectral frequency of electromyographic activity. Jaeger et al. analyzed a task using a three-dimensional dy- namic biomechanical model. Based on their ob- servation and analysis they make task design rec- ommendations. Parnianpour et al. measured tri- axial isometric strength of males in all six possible directions in three different postures. Han et al. propose a nonlinear optimization biomechanical model for the analysis of construction and other work.

The construction industry is a complex industry with numerous trades. Each of these trades are

unique in themselves with specific ergonomic chal- lenges. While the methodologies employed in this collection of papers may address some of the issues which cut across many trades, it is recog- nized that numerous others have been left un- touched. Given the paucity of activity in this area, it is a special challenge to ergonomics profes- sionals to begin to fill that void.

Shrawan Kumar Dept. of Physical Therapy

University of Alberta Edmonton, Alberta T6G 2(34

Canada