In order to examine risk assessment for formaldehyde exposure among medical technicians of a hospital pathological section, we conducted formaldehyde exposure measurements using passive samplers in cooperation with nine medical technicians working at two hospitals. We conducted two types of formaldehyde exposure measurements, long-term exposure measurements (n=30) that deal with the limit of exposure measured as a time-weighted average, and short-term exposure measurements (n=11) specifying the maximum exposure for a short-term event; a ceiling value.
The average of the long-term exposure measurements (n=30) was 0.1 ppm (SD: 0.09 ppm, range: 0.01-0.32 ppm), with two thirds exceeding the Japanese exposure limit (0.1 ppm). The long-term exposure values have a significant positive correlation with duration of exposure to formaldehyde rather than with total work time (Pearson's correlation: 0.791, p=0.000). The rate of overexposure (>0.1ppm) for an exposure duration longer than 60 min (60%, 9/15) was significantly higher (χ2-test, p=0.005) than for exposure duration less than 60 min (6.7%, 1/15). Regarding short-term exposure measurements (n=11), there was no significant positive correlation between the exposure value and exposure duration. However, approximately half exceeded the OEL-C (0.2 ppm) level proposed by the Japan Society for Occupational Health or the TLV-C (0.3 ppm) level proposed by ACGIH. Considering the results of risk assessment for formaldehyde exposure, medical technicians working in hospital pathological sections could avoid exposure to a high concentration of formaldehyde by improving the handling of pathological samples. Tasks that involve exposure to formaldehyde should be performed in draft chamber with a local ventilation system.

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We attempted to introduce occupational safety and health management systems (OSHMS) into a local government office, at which many different types of jobs are performed, and discuss the process and outcomes. The introduction of the program was based on risk assessment and participatory activities leading to continuous improvements at workplaces. This intervention study was conducted at a local government office, comprising about 2,000 workers and 10 occupational safety and health committees (OSH committees, 14 departments). We conducted an OSHMS introduction program four times between June 2007 and June 2008, a baseline self-reported questionnaire survey was conducted in August 2008, a risk assessment training program was held for the ten OSH committees, and simultaneously an occupational stress reduction training program was held twice between August 2008 and May 2009. The questionnaire survey showed that hazardous working environments were significantly related to higher psychological and physical stress levels at workplaces. These results may indicate that plotting working environments vs. psychological and physical [stress][distress] is a useful tool in risk assessment training programs. According to the results of the questionnaire survey, blue-collar workers proposed improvements for working environments more frequently compared to clerical workers, while clerical workers submitted a number of reports on good practices and proposals on how to improve working environments after participating in the occupational stress reduction training program. These results may indicate that the worker's attitude to and actions for occupational safety and health was activated by a series of risk assessment training programs. Therefore, a training program with a risk assessment approach is effective in advancing practical OSH activities. Furthermore, the incidence of occupational accidents has decreased about 50 % within two years.

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In construction industry as which implementation of the risk assessment in working place was determined with enforcement of revised labor security and Occupational Safety and Health Law in April, 2006. During the 2006 fiscal year to the 2008 fiscal year, the actual condition of the risk assessment introduction in the construction industry was investigated. As a result, It became clear that there are work by which the danger is not fully evaluated even if it is the work to which death labor accident is occurring frequently etc. in small and medium-sized enterprises. To solve such a subject, data analysis was conducted for the death labor accident of the construction industry in Japan, and work especially with the high degree of critical etc. was extracted.
In order to support the risk proper evaluation of small and medium-sized enterprises in the construction industry, it is effective to perform these information offers.

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British HSE has introduced a target safety level that should result in the incidence of work-related deaths being less than 10^-6 times per year. However, the general methodology to achieve this target is not necessarily clear. This study proposes an equation that is able to estimate the probability of occurrence of accidents in a man-machine working system quantitatively based on Markov analysis. Based on this equation, the following result was obtained. 1) It will be difficult to achieve the target objective if only the machines' users take countermeasures (safety management) that depend on workers' attentiveness. It is vital to apply a wide range of duplicate and automated monitoring technology. 2) It will be possible to achieve the target objective under the following conditions - less than 10^-5 hour (around 30 msec.) as the test interval for the sensor and processor-related safety function on a single control system, less than 0.05 hour (3 minutes) as a test interval on diverse duplicate control systems, less than 0.5 hour (30 minutes) as the test interval on diverse triple redundancy control systems. 3) The above-mentioned target cannot be achieved for hazardous point operations. However, when probability of occurrence of accidents that cause worker death is set at less than 10^-4 times per year as a target value , this target might be able to be achieved through integration between implemented protective measures (safety of machinery) and safety management.

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"Guideline for the comprehensive safety standards of machinery" and JIS B 9700 " safety of machinery" are producing remarkable results in a risk-based approach to safety of machinery in industry. However, the risk-based approach to safety at machine manufacturers and machine users is mostly limited to the design and operating phases. This paper addresses topics for future study in a risk-based approach to safety of machine and risk analysis methods to be utilized over the entire lifecycle of a machine. The level of machine safety obtained from risk-based approach in the design phase must be maintained over the entire lifecycle of the machine. As safety and quality are two sides of the same coin, this paper also describes the quality management needed to ensure safety of machine referring to the mechanical integrity of safety design stipulated in OSHA/PSM.

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We investigated the relationship between emotional load and behavioral fatigue in a simulation of long-time intensive work. Sixteen male participants (mean age, 27.3 yr; range, 19-38 yr) were required to attend a laboratory for 16 consecutive nights for recording under the following conditions: adaptation night (23:00-07:00), baseline night (23:00-07:00), sleep restriction nights 1-10 (01:00-06:00), and recovery nights 1-4 (23:00-07:00). To describe the relationship clearly, we focused on two representative cases, the first being the participant with the highest recorded emotional load of all the participants (Case-A), and second was the participant who was the most controllable for expressing the emotional load during this experiment (Case-B).
The results showed the characteristic symptoms for Case-A to be "bad-tempered" and "very angry". Since the percentage for each of these symptoms was 1.3% and 1.1%, respectively, in all participants, it is hypothesized that these symptoms are characteristic signs of over-fatigue. In contrast, Case-B did not show severe emotional symptoms during this experiment, unlike Case-A. It should be noted that in both cases there was a tendency such that the more extreme the behavioral fatigue, the lower the emotional load, or vice versa. From these results, we considered that there is probably a trade-off between emotional load and behavioral fatigue.

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After the amendment to the Occupational Safety & Health Law in 2006, an increasing number of manufacturers and users areimplementing risk assessment to ensure the safety of industrial machines. This article describes best practice at a machine manufacturer and at a machine user in Japan, with regard to organization and methods for implementing risk assessment and risk reduction, using actual machines as examples. It clearly shown that the user could not obtain information on correct use including residual risks of the newly ordered machine, until the user requested such information to the manufacturer, in line with the Safety Guideline issued by the Ministry of Health, Labor and Welfare. It is expected that, as shown by these cases, risk assessment in proper methods and risk reduction based on safety technology have been widely adopted in Japan.

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[in Japanese]

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[in Japanese]

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