Sussell A, Hart C, Wild D, Ashley K
National Institute for Occupational Safety and Health, Cincinnati, Ohio, USA.
Appl Occup Environ Hyg. 1999 Mar;14(3):177-85. doi: 10.1080/104732299303142.
We evaluated worker lead exposures and cleaning effectiveness during initial cleanup of 19th-century buildings with highly deteriorated lead-based paint. Eighteen rooms of similar size and condition in two university-owned buildings were selected for a pilot project to compare three methods for removing loose paint, paint chips, and dust. The methods used were: dry scraping followed by dry sweeping (no engineering or work practice controls); wet scraping and high-efficiency particulate air (HEPA) vacuuming; and the latter method with the addition of a portable HEPA-filtered exhaust fan in the room providing about 40 air changes per hour. The final step for all methods was wet-mopping once with tri-sodium phosphate solution. During a single day 18 rooms were cleaned; each of three two-person work crews cleaned six rooms, two with each method. Air and surface samples were collected before, during, and after cleaning. All of the methods were potentially hazardous to workers: 44 percent of the method-based exposures (range: 5.0-360 micrograms/m3) and one of five full-shift exposures exceeded the OSHA PEL (range 9.4-110 micrograms/m3). Lowest worker exposures were during the wet scraping and vacuuming method (mean: 24 micrograms/m3). Providing general ventilation in rooms did not reduce worker exposures and appeared to increase them (mean: 73 micrograms/m3). Overall, the mean floor surface lead levels were reduced 50 percent after cleaning (from 2,600 to 1,300 micrograms/ft2), but the effectiveness of the three methods in reducing floor lead levels did not differ significantly. Overall, the method, mean paint lead concentration, pre-cleaning surface lead concentration, and work crew were significantly associated with the mean worker exposures during cleaning (p = 0.023), but not with the post-cleaning surface lead concentrations (p = 0.13).
我们评估了在对19世纪含严重劣化铅基涂料的建筑物进行初步清理期间工人的铅暴露情况以及清洁效果。在两座大学所属建筑中挑选了18个大小和状况相似的房间进行一个试点项目，以比较三种清除松散涂料、漆屑和灰尘的方法。所使用的方法有：先干刮然后干扫（无工程或工作规范控制）；湿刮并使用高效空气过滤器（HEPA）吸尘；以及后一种方法再加上在房间内增设一台每小时提供约40次换气的便携式HEPA过滤排气扇。所有方法的最后一步都是用磷酸三钠溶液湿拖一次。在一天内清理了18个房间；三个两人工作小组每组清理六个房间，每种方法各清理两个房间。在清理前、清理期间和清理后采集了空气和表面样本。所有方法对工人都有潜在危害：基于方法的暴露中有44%（范围：5.0 - 360微克/立方米）以及五次全时暴露中的一次超过了职业安全与健康管理局（OSHA）的允许接触限值（范围9.4 - 110微克/立方米）。工人暴露最低的是在湿刮和吸尘方法期间（平均值：24微克/立方米）。在房间内提供全面通风并没有降低工人的暴露，反而似乎增加了暴露（平均值：73微克/立方米）。总体而言，清理后地面表面铅水平平均降低了50%（从2600微克/平方英尺降至1300微克/平方英尺），但三种方法在降低地面铅水平方面的效果没有显著差异。总体而言，方法、平均涂料铅浓度、清理前表面铅浓度和工作小组与清理期间工人的平均暴露显著相关（p = 0.023），但与清理后表面铅浓度无关（p = 0.13）。
