This paper reports the validity of the vibration-type electrostatic field sensors with respect to the electrostatic charging measurements of pneumatically transported powders. The pneumatic powder transport facility and polypropylene (PP) powders were used for this study. The feeding mass and velocity of the PP powders were 0.4 kg/s and 10.6 m/s, respectively, and a Faraday cage was set inside a silo. The value of the electrostatic field and the charging amount of the PP powder that was controlled by a DC-type ionizer were compared. It was observed that the two were clearly in direct correlation. The values obtained from the electrostatic field sensor were similar to those that were transferred from the charging amount obtained from the Faraday cage method. The electrostatic field sensor generally performed well and its validity was confirmed.
There is the opinion that a European system for machine safety should be introduced in Japan to achieve a desirable level of occupational safety. Occupational safety is secured by adopting a system in which the risk is managed by avoiding, reducing, transferring, and accepting it, after all risks have been considered. Machine safety, meanwhile, is secured by adopting a system in which risks are reduced one by one. The current study proposed a method in which the occupational safety system is incorporated into the machine safety system as a risk-reduction measure; this method makes use of risk management. The theoretical framework used to achieve this was the International Organization for Standardization 31000:2009 “Risk Management–Principles and Guidelines.” In this risk management, a system is needed that validates activities for preventing occupational accidents at work sites in order to compensate for inadequacies in the machine safety system relating to occupational accidents. The purpose of this form of risk management is to prepare the social environment to support autonomous safety and health activities, and to develop measures to cope with work-site risks, all in the form of a social system. With this form of risk management, uncertainty within systems and measures must be handled as a risk. This idea differs from that of conventional occupational safety in terms of its understanding of risk. The current study proposed macroscopic and microscopic occupational safety: the former pertains to uncertainty that exists in the social environment surrounding work sites, while the latter pertains to uncertainty that exists in autonomous safety and health activities performed at work sites.
Objectives: There are no reports pertaining to radiation protection and education in veterinary hospitals that specifically target veterinary nurses. Therefore, we investigated whether veterinary nurses have adequate basic knowledge and understanding of radiation, and whether they are skilled to perform radiation safety practices.
Subjects and Methods: A total of 255 veterinary nurses attending various veterinary nursing seminars were recruited for this investigation. Of these, 230 who specialized in the care of a variety of animals provided valid responses (valid response rate: 90.9%).
Results: When asked the question, “When assisting with X-ray imaging inspection, do you experience anxiety regarding radiation damage?”, 45% of respondents answered that they were “anxious.” Dose monitoring practices were correctly carried out by less than half of respondents. Less than 30% of respondents answered, “I know my exposure dose.”
Consideration: Our investigation revealed that veterinary nurses generally lacked knowledge and understanding of radiation. We suggest that such information should be integrated into undergraduate and postgraduate education curricula. An immediate need is to create a control system for radiation protection. Detailed research will be necessary to ensure proper implementation of educational measures. Moreover, it will be necessary to further improve the efficacy of occupational health activities in veterinary hospitals.
Uniform criteria that are accepted publicly for judging and evaluating risks have yet to be established. Consequently, the policy derived from risk-assessment results relies on the subjective views of the persons who conduct the risk assessment, and the validity of the results is not necessarily assured. This study showed that there are limits to avoiding this issue within the scope of autonomous occupational safety and health activities at a single place of business. Therefore, a system is required in which the risk reduction states of machinery are individually and specifically verified by third parties who are knowledgeable of safety standards and good practices. We defined this as “validation” and investigated four European countries where machinery safety centered on the implementation of risk assessment has been promoted in advance of Japan. As a result, it was found that labor standards inspection could contain an activity equivalent to “validation” within the framework of the current Japanese social institutions. Moreover, the following two points particularly need to be reviewed: (1) clarifying the relationship of laws and regulations with industrial standards pertaining to machinery safety so that they are closely linked, and (2) collecting and widely disseminating information about good practices which are identified through inspections to prevent machinery-related accidents.
As a result of the lessons from the TEPCO Fukushima Daiichi Nuclear Power Plant Accident of 2011, the Ministry of Health, Labour and Welfare (MHLW) examined the management principles of radiation exposure dose in an emergency from the results reported in many documented reviews with an aim to prepare for a future accident in a nuclear facility.
The examination essentially included justifying and optimizing principles of the International Commission on Radiological Protection (ICRP), justifying the upper limit of emergency exposure, and crisis control protocol of a nuclear facility disaster.
The MHLW promulgated the revised Ordinance on Prevention of Ionizing Radiation Hazards based on the examination results in August 2015.
I have introduced the examination results of the Food Safety Commission and the working group pertaining to risk management of low-dose radiation exposure after reviewing the documents describing influence of such exposure.
If we examine the exposure dose management policy of radiation workers, it is necessary to consider health effects resulting from chronic exposure to low-dose radiation as well as from acute exposure to high-dose radiation. Thus, it is necessary to diligently promote epidemiologic studies that provide long-term follow-up for the workers.