Workplace Aerosol Sampling at Realistic Low Windspeeds

描述：气溶胶采样器仍然很重要，因为它们在评估（从而控制）工人接触空气中颗粒物方面发挥着重要作用。呼吸系统疾病，包括哮喘和慢性阻塞性肺病，仍然是诺拉的主要优先领域。拟议的研究是在RO 1-OH 02984-02（1994-1998）、5 RO 1-OH 03687-03（1998-2002）和5 RO 1-OH 02984-06（1999-2003）下开展的一系列工作的延续，补充了其他资源支持的实地研究。这一新项目将包括进一步的实验室研究，以便在以往研究未涵盖的实际低风速条件下（0.05至0.5米/秒）开发有意义的气溶胶采样方法。具体目标是：（a）开发一种新的实验室实验系统，用以评估大多数工作场所低风速下的气溶胶采样器;（B）利用该系统评估基于级联撞击器的气溶胶采样系统，该系统将提供关于工人接触气溶胶的颗粒大小分布的信息;（c）确定人体吸入的效率（使用人体模型）在非常低的风速下，考虑到受试者的呼吸模式和体温的影响;（d）描述一系列候选个人可吸入气溶胶采样器在这种条件下使用时的性能;（e）利用这种性能信息解释不同采样器在实际实验室环境中使用时的质量偏差（并将结论与实地研究中观察到的情况联系起来）。早期的工作对制定职业接触标准和建立有关的接触评估方法产生了影响。然而，仍然存在相当大的知识差距。我们仍然无法解释具体的个人采样器在多大程度上反映了工人的实际接触，也无法解释使用各种推荐采样器进行的工作场所接触评估之间的差异。新的研究将填补这些空白，并将职业气溶胶暴露评估置于更坚实的基础上。

DESCRIPTION: Aerosol samplers remain important through their role in the assessment (and hence control) of workers' exposures to airborne particles. Respiratory ill-health, including asthma and chronic obstructive pulmonary disease, remain major NORA priority areas. The proposed research is a continuation of a body of work carried out under RO1-OH 02984-02 (1994-1998), and then 5 RO1-OH 03687-03 (1998-2002) and 5 RO1 OH 02984-06 (1999-2003), complementing field studies supported from other resources. This new project will contain further laboratory research to develop meaningful aerosol sampling methodology under realistically low windspeed conditions not covered by previous research (0.05 to 0.5 m/s). The specific aims are to: a) develop a novel laboratory-based experimental system by which to evaluate aerosol samplers at the low windspeeds found in most workplaces; (b) use it to evaluate cascade impactor- based aerosol sampling systems that will provide information about the particle size distributions in workers' aerosol exposures; (c) define the efficiency of human inhalation (using a mannequin) at very low windspeed, allowing for the effects of the breathing patterns of the subject and body heat; (d) characterize the performances of a range of candidate personal inhalable aerosol samplers when used under such conditions; and (e) use such performance information to explain the mass biases between different samplers when they are used in realistic laboratory environments (and to relate the conclusions to what is observed in field studies). Earlier work has been influential in the setting of occupational exposure standards and in establishing relevant exposure assessment methods. Yet there remain considerable knowledge gaps. We are still unable to explain the extent to which specific personal samplers reflect actual worker exposure, or to explain differences between workplace exposure assessments using various recommended samplers. The new research will fill these gaps and place occupational aerosol exposure assessment on a still firmer footing.