LAUSR

involving the control of hazardous factors, such as harmful airborne chemical substances and physical factors, that workers encounter in their workplace and the prevention of health problems caused by such factors using science and engineering knowledge and techniques. This definition and purpose closely resemble those for industrial hygiene in other countries. However, the Japanese occupational health system has a unique administrative principle called the “three-management strategy”. Considering that industrial hygiene falls under occupational health, it is also required to follow this principle. The “three-management strategy” is the philosophy that workers’ health should be ensured by completing the following three matters: · Work management: Reducing the load on individual workers by optimizing their work hours, workload, work methods, work cycles, and work posture. Ensuring that workers wear the necessary protective equipment. · Working environment control: Assessing the risk of harmful substances, such as organic solvents, dust, heavy metals, and several physical factors, in the working environment. Controlling and eliminating them as best as possible using a ventilation system, etc. · Health care: Preventing health problems of workers by determining their health conditions through health checkups and implementing appropriate measures and health guidance based on the results of the checkups. The current Japanese industrial hygiene system is mainly responsible for providing the information and technologies necessary for work management and working environment control. Therefore, regardless of propriety, the Japanese industrial hygiene system tends to focus more on supporting administrative measures rather than basic scientific research. The “administrative control level” is one example of such characteristics of the Japanese industrial hygiene system and is one of the benchmarks for evaluating the risk of worker exposure. However, it is not the direct reference for personal exposure that many other countries have adopted. The correct definition of “administrative control level” is “the reference for evaluating the effectiveness of working environment control”, which is based on the notion that lowering the environmental concentration will consequently lower personal exposure. Thus, in principle, area sampling is adopted instead of personal sampling when measuring the concentration of hazardous chemical substances in working environments throughout Japan. The following outlines the brief history of industrial hygiene in Japan from its substantial birth to present-day circumstances. Many research subjects have now been added to the Japanese industrial hygiene, such as heat, noise, vibration, ionizing radiation, high-pressure gas, and hazardous rays. At the beginning, however, the most important issue for Japanese industrial hygiene was countermeasures against exposure to organic solvents, which prompted the addition of dust control to the issues a little later.