静電気帯電現象が様々な障害や災害を引き起こすことは周知のとおりである.静電気帯電を原因とするトラブルには，静電気引力による埃の付着や日常的に経験する静電気放電時に受ける痛み，不快感，冬季の乾燥期に発生する脱衣時の静電気放電音など比較的軽微なものから静電気帯電を原因とする爆発や火災事故のように極めて深刻な事例に至るまで実に多くの事象が報告されている.今から10年以上前のことになるが，製油所の原油貯蔵タンクで静電気帯電が原因と考えられる火災が発生し，7名の作業員のうち5名が死亡，2名が軽傷を負う大事故となった.当時の新聞報道から作茉員は静電気帯電防止作業服を若mしていたものと推測される.%Safety quality on the static electrical propensity of work clothes in Japan is confirmed by electrical resistivity or friction al electric charge obtained from the results of test methods specified by International Electrotechnical Commission standard (IEC) or Japanese Industrial Standard (JIS). In practical use, we consider that the hazard related to static electrical charge is dependent on human body voltage caused by various movement of worker during working hours as well as electrical resistance or electric charge amount of work clothes. We thought up two trial movements for determination of human body voltage: one is taking off movement after performing fractional action between work clothes and inner wear during 20 seconds at speed of 90 times per one second, and the other is standing up from the seat of popular use chair quickly after performing frictional action between the back part of work clothes and the back of a chair during 60 seconds at speed of 90 times per one second. Experimental works were performed by using four types of unprotected commercial work clothes and six types of static protected commercial work clothes. As the experimental results, standing up movements from the seat of chair were recorded higher human body voltages than taking off movement. From the almost all work clothes including static protected work clothes, the human body voltage above 3000 voltage which many human felt static electrical shock were detected by the standing up from the chair quickly after performing mctional action.
展开▼
