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Lean manufacturing or also known as lean production has been one of the most popular paradigms in waste elimination in the manufacturing and service industry. Thus, many firms have grabbed the benefits to practice lean manufacturing in order to enhance quality and productivity. However, previous research shows that there are various sets of tools or techniques that had been adopted at a certain degree across firms according to their own understanding of lean manufacturing. The scenario resulted with varying leanness measures in order to measure lean practices. This paper describes a preliminary study in developing a conceptual model to measure leanness in manufacturing industry. Thorough literature survey, books and report analysis contribute to the main preliminary analysis of this study. The most common tools or techniques and their usefulness have been investigated. In this research, a conceptual model for leanness measurement in the manufacturing industry has been developed and designed in two main levels, namely the dimensions and the factors. There are seven main dimensions in measuring leanness in lean manufacturing practices such as manufacturing process and equipment, manufacturing planning and scheduling, visual information system, Supplier relationship, customer relationship, workforce and product development & technology. In addition, the model also shows how lean dimensions in the manufacturing system relate to eight types of wastes.

The word “lean” refers to lean manufacturing or lean production as it uses less of everything, compared to mass production. It only uses half of the human effort in the factory, half of the manufacturing space, half of the investment in tools and half of the engineering hours to develop a new product in half the time [1, 2]. Based on the research conducted by Bayou and Korvin [3], manufacturing leanness is a strategy to earn less input to better achieve the organization’s goals through producing better output, where ‘‘input’’ refers to the physical quantity of resources used and their costs, and ‘‘output’’ refers to the quality and quantity of the products sold and the corresponding customer services. In another review of lean manufacturing, Narasimhan et al. [4], have concluded that the efficient use of resources through the minimization of waste is the essential aspect of leanness as the aim of lean manufacturing is to reduce waste and non-value added activities. Essentially, the core idea of lean manufacturing is to maximize customer value while minimizing waste. The ultimate goal of implementing lean production in an operation is to increase productivity, enhance quality, shorten lead times, reduce cost and so on [5].These factors indicate the performance of a lean production system. Some claim that lean manufacturing techniques were first identified as a cause of Japanese success. The supported idea is based on the fact that the lean management model was first developed at Toyota Motor Company by the Japanese after the Second World War in their effort to reduce cost. Therefore, the introduction of lean has significantly changed the market and the strategy during its first emergence in the development of the car industry that was pioneered by Toyota Production System (TPS). The success of TPS shows and proves that lean techniques are powerful and significant. The overwhelming scenario has led other companies from different industries such as electric and electronics [6-8], automotive [3, 9], auto and machinery [10], wood [11], ceramic [12], machine tool industry [13] and so on to implement lean in their manufacturing. However, most of the companies have implemented lean and have assessed lean practice in their own unique way. The reason for this scenario lies in their internal issues such as lack of knowledge and their understanding of lean, culture, skills and so on. Other factors such as age [14] and size [8, 10, 14] of the company also contribute to the degree of adoption of lean tools or techniques in one’s company. Thus, these situations have a big implication on the companies by restricting them in the measurement or comparison of their performance across companies and industries. Some of the companies have also given up continuing practicing lean due to the mentioned factors. Therefore, a research should be conducted to identify and determine the determinants or indicators for leanness measurement in the manufacturing companies.

This study was undertaken to design the conceptual model for lean manufacturing measurement in the manufacturing industry. Initially, the factors or determinants that contribute to the measurement of lean practices have been identified. Similar practices/tools/techniques with the same characteristics are grouped into the same dimension. Thus, the result of this research has shown that there are seven main dimensions that contribute to leanness measurement in manufacturing. We limit our model development by considering and selecting thepractice/tool/technique that is proposed by the empirical approach or a combination of both quantitative and qualitative approaches as the aim of the study is to provide a general guideline for all companies and industries in the manufacturing sector. Elsewhere in this study, it has been mentioned that the quantitative approach has resulted with a measure of lean index which is unique for the particular unit analysis of the author’s study. On the other hand, these findings have enhanced our understanding of lean concepts and the determinants of variables which contribute to the progress towards leanness. Further work needs to establish whether the relationship between the dimensions and wastes are true by conducting the Delphi method approach. The conceptual model can also be modelled into a diagnostic model for leanness measurement in future work. Practitioners and scholars may benefit from this study as it will aid in improving the general effectiveness of the strategic manufacturing performance.