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Research paper : Improving the reliability of temperature measurements taken with clinical infrared ear thermometers (J. Ishii)−51−Synthesiology - English edition Vol.1 No.1 (2008) management system of the Measurement Law, the main body of management is the government (Ministry of Economy, Trade and Industry) that administers the law, and testing and inspection are also conducted according to rules set by the Measurement Law. All clinical thermometers sold on the market are guaranteed by the government to have certain level of specification and accuracy designated by law, and consumers and users, who may not have technical knowledge of the product, can expect to be able to purchase and use a measuring instrument of a certain quality.In case measurement management is based on Measurement Law, detailed rules and standard must be determined for procedures and equipments for calibration and assessment. Although this scheme is extremely important from the point of fairness and openness of calibration and assessment, the manufacturer’s technological autonomy for measurement management may decrease accordingly. This may become an obstruction for improving production performance (accuracy) through new technical development as well as new product development. In other words, management by Measurement Law is effective in case the methods and equipment for calibration and assessment are commonly available and the product technology has already matured.Reviews were done by the Survey and Research Committee for New Clinical Thermometer and subsequent JIS Committee established in 2000 for the adequacy of designating ear thermometers as specified measuring instruments. As a result, for ear thermometers, it was concluded that designation of a specified measuring instrument by Measurement Law should be left as a matter of future deliberation for the following reasons: (1) a common method and equipment of calibration and assessment are not widely available among manufacturers, and (2) the product technology is still in a development phase, so early regulation by law has the risk of withholding the advancement of product technology in future.4.2 Measurement management system by industrial standardization Measurement management system based on autonomous activity of manufacturers by technical standardization (industrial standard document) is thought to be on the opposite end of enforced measurement management by Measurement Law. High quality working standard BBR can be realized by manufacturers by establishing composition and specification of the practical BBR accordong to an industrial standard document such as JIS, and by sharing essential technology including quality management process. In addition, by using contact thermometer, for which traceability to the national standard is established, as reference thermometer, it can be expected that the manufacturers will conduct calibration and assessment at a certain target level or higher.If such measurement management system can be introduced, merits include: (1) the government sector will not have to take on more work because it will not be required to launch a new calibration service, and (2) compared to regulation by the Measurement Law (Section 4.1), improvement of calibration and assessment technology and standard equipment can be done flexibly and easily to accommodate future product developments, and therefore will not obstruct development and efficiency of the manufacturers’ own calibration and assessment technology. On the other hand, total dependence on autonomous system of industrial standard does not have the force of regulation by law, so introduction and operation of technology and equipment will be done under the responsibility of the manufacturers of clinical thermometers. Moreover, since sharing of technological information including standard facility will be limited almost entirely to documented information, there is a risk that it may not be applied appropriately in practice.To review the adequacy of the above measurement management system from a technical aspect, AIST conducted questionnaire survey on standard facility and measurement management approach used by manufacturers and retailers of ear thermometers in Japan through opportunities such as Standardization Committee, and also actually visited the manufacturers. According to the result, many manufacturers already had large-scale manufacturing and inspection processes for ear thermometers, and many had already introduced and were operating standard equipment (working standard BBR) created on their own. Therefore, in the situation at the time, even if AIST led the standardization of working standard BBR, it was determined that, for economic reasons, it would be difficult for the companies to replace the standard equipment immediately. Moreover, manufacturers of ear thermometers overall had high technology for mercury-in-glass thermometers and thermistor electronic thermometers, but did not have advanced technological experience in managing BBR for ear thermometers, which differed greatly in principle. Therefore, it was concluded that maintaining long-term reliability of ear thermometer in the Japanese market under measurement management system by industrial standardization only was not practical at the time.4.3 Measurement management system based on calibration service for radiance temperature scale by the governmentBased on the conclusions of Sections 4.1 and 4.2, a measurement management system in which AIST provides new calibration service for radiance temperature scale of working standard BBR in industry was considered. This system is positioned between the aforementioned two cases.In case of Section 4.2, traceability to national standard is maintained for the reference contact thermometer of working standard BBR, while the blackbody cavity is regulated by

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