The study of glass substrate dust exposure improvement in crush work

• Main Authors: Liang, Jia-Shao, 梁家韶
• Other Authors: Tsai, Chuen-Jinn
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/62pfq6

碩士 === 國立交通大學 === 工學院產業安全與防災學程 === 105 === The main raw material of the TFT glass substrate is silicon dioxide, which accounts for 55±5 % in the compositive contents. A number of studies have found that exposure to silicon dioxide can cause silicosis, pneumonia and increased carcinogenicity and other related complications. To protect the health of workers, it is bound to control its exposure under allowable concentration. Generally speaking, the most effective method to improve the environment of dust exposure is local exhaust, which can trap the dust before it get into human breathing zone. However, due to the lack of standards and professional design, the system usually presents as inadequate wind speed. Furthermore, due to the difficulty of improving existing equipment, the influence on production process, and the high cost of improvement, local exhaust is not the most favoring way to trap the dust. This study takes the glass grinding dust exposure process on in a glass substrate manufacturing as research object, to examine the environmental monitoring work over the years, the staff work patterns and the efficiency of control measures. MOUDI method is adopted to examine dust particle size distribution, and establish improvement measures by particle size and job type states. The result suggests that the most dust particles in working area are large dust size particles, and the improvement measures are decided by according to the motion characteristics of dust particle size of the formulation. Furthermore, DUSTTRAK8530 is adopted to examine the effectiveness of the improvement measures, and the measures include changing the contents of broken glass types, prohibit the use of the equipment could easily lead dust, close pollutant sources, clean pollutant materials around the sources. Finally, we choose the most efficient improvement measure and improve it according to its feasibility, and then assess the effects of improved dust concentration by sampling method suggested in the working environment monitoring method. The result showed that using only local exhaust ventilation(LEV), the average dust concentration in air is 0.034 mg⁄m^3 . However, when we operated LEV with measures above, dust concentration has reduced by 70.6 %(measure 1, value:0.01mg/m3), 79.4 %(measure 2, value:0.007 mg⁄m^3 ), 55.9 %(measure 3, value:0.015 mg⁄m^3 ), 44.1 %(measure 4, value:0.019 mg⁄m^3 ). According to the working environment measurement and NIOSH Manual of Analytical Methods, we comprehensively evaluated the decrease of dust concentration and measures above; the result is that measure 3 and measure 4 were found to be effective and suitable for institutions. When we operated LEV with measure3 and with measure4 the total dust concentration is decreased by 55.2 %(from 0.58 mg⁄m^3 to 0.26 mg⁄m^3 ) and 37.9 %(from 0.58 mg⁄m^3 to 0.36 mg⁄m^3 ).Either measure 3 or measure 4 has the ability to restrict concentration below regulatory limits.