Crystalline Silica and RSP Control Methods Effectiveness during Concrete Grinding

混凝土研磨过程中结晶二氧化硅和 RSP 控制方法的有效性

基本信息

批准号：
7302577
负责人：
FARHANG AKBAR-KHANZADEH
金额：
$ 18.54万
依托单位：
UNIVERSITY OF TOLEDO HEALTH SCI CAMPUS
依托单位国家：
美国
项目类别：
财政年份：
2007
资助国家：
美国
起止时间：
2007-09-01 至 2009-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7302577
关键词：
Crystalline Silica RSP Control Methods

项目摘要

DESCRIPTION (provided by applicant): Concrete surface grinding generates one of the highest levels of crystalline silica dust in the construction industry, exposing concrete grinders to unacceptable levels of this highly toxic chemical linked to a variety of respiratory and other diseases. The proposed study, a follow up of our recently completed pilot project funded by the National Institute for Occupational Safety and Health (NIOSH) through the Center to Protect Workers' Rights, covers multiple NIOSH NORA priority areas: intervention effectiveness research, chronic pulmonary diseases, control technology and exposure assessment. This study's long-term goal is to characterize/prevent silica dust exposure during construction activities. It's short-term goal is to determine the feasibility, limitations and effectiveness of additional available dust control methods in enhancing existing dust control methods during concrete grinding. Our pilot study confirmed previous studies' findings, including our study in 2002, that the commonly used approaches do not reduce silica dust to acceptable levels. The proposed study will demonstrate the effects of major relevant influencing factors and will reveal the combinations of those factors that effectively control silica dust. The study will be performed in a controlled environment (a field laboratory) to collect data. Silica dust sampling parameters (factors) will be as follows: (a) grinding techniques: uncontrolled 1 (conventional-grinding), controlled 2 (wet-grinding and ventilated- grinding); (b) grinder diameter sizes: 3 (4.5-inch, 7-inch and 9-inch); (c) general ventilation position: 2 (on, off); (d) sampling time set up: 3 (conventional- grinding 5,15, 25 min, wet-grinding 30, 45, 60 min, ventilated- grinding 45, 60, 90 min); (e) control method flow-rate: conventional-grinding 1 (0, no water or airflow), wet- grinding water flow 3 [0.2, 0.4, 0.8 L/min/inch diameter], and ventilated-grinding airflow-rate 3 (0.25, 0.50, 1.0 L/min/inch diameter). Thus, the (1 x 3 x 2 x 3 x 1) factorial design applies to uncontrolled conventional- grinding and the (2 x 3 x 2 x 3 x 3) factorial design applies to wet-grinding and ventilated-grinding. At each factor level, 2 personal samples (replicate) will be collected and their average value will be reported as the silica concentration for that factor level. The total resulting number of air samples will be 252. For quality control, 28 blank, 30 background and 20 bulk samples will also be collected. Multiple analyses of variance will be used to analyze the data to find the desired combination of factors.

描述（由申请人提供）：混凝土表面研磨会产生建筑行业中最高含量的结晶二氧化硅粉尘之一，使混凝土研磨机暴露于这种与多种呼吸道疾病和其他疾病有关的剧毒化学物质的不可接受的水平。拟议的研究是我们最近完成的试点项目的后续项目，该项目由国家职业安全与健康研究所 (NIOSH) 通过保护工人权利中心资助，涵盖多个 NIOSH NORA 优先领域：干预效果研究、慢性肺部疾病、控制技术和暴露评估。这项研究的长期目标是描述/防止施工活动期间二氧化硅粉尘的暴露。其短期目标是确定其他可用粉尘控制方法在增强混凝土研磨过程中现有粉尘控制方法方面的可行性、局限性和有效性。我们的试点研究证实了之前的研究结果，包括我们 2002 年的研究，即常用的方法不能将硅尘减少到可接受的水平。拟议的研究将论证主要相关影响因素的影响，并将揭示有效控制硅尘的这些因素的组合。该研究将在受控环境（现场实验室）中进行以收集数据。硅尘取样参数（因子）如下：（a）研磨工艺：非受控1（常规研磨），受控2（湿磨和通风研磨）； (b) 磨床直径尺寸：3种（4.5英寸、7英寸和9英寸）； (c) 一般通风位置：2个（开、关）； (d) 采样时间设置：3次(常规-研磨5,15,25分钟，湿式研磨30,45,60分钟，通风-研磨45,60,90分钟)； (e) 控制方式流量：常规研磨1（0、无水或气流）、湿式研磨水流量3[0.2、0.4、0.8L/min/英寸直径]、通风研磨气流3 （0.25、0.50、1.0 升/分钟/英寸直径）。因此，(1 x 3 x 2 x 3 x 1) 因子设计适用于不受控制的常规研磨，(2 x 3 x 2 x 3 x 3) 因子设计适用于湿磨和通风研磨。在每个因子水平，将收集 2 个个人样本（重复），并将其平均值报告为该因子水平的二氧化硅浓度。空气样本总数为 252 个。为了进行质量控制，还将收集 28 个空白样本、30 个背景样本和 20 个散装样本。将使用多重方差分析来分析数据，以找到所需的因素组合。