PM2.5纳入国家环境空气标准_资讯动态_森井除湿机
资讯动态

PM2.5纳入国家环境空气标准

返回时间: 2011-12-16 16:23:20 字体 A+A-

来自:美国政府环保署官方网站
     微粒物质,又成为PM, 是包括空气里的固体粒子和在空气里的水份。PM的形成是由许多人为的因素或大自然自己散发出来的,也有污染物与空气产生相互反应而产生。这些固体或液体的物质是以各种各样的不同体积而存在。
     当微粒小于10微米的直径时,就会被通过呼吸,吸进人体和积聚在人的呼吸系统,从而影响人体的健康。对于微粒小于2.5微米,就被称为细小微粒,这些微粒对人体健康影响是最大的。因为它小于平均人类头发7份1的体积,很容易被藏在人的肺部深处。
     健康研究数据表明,人的过早死亡与接触细小微粒有非常明显的关系。另外一个重要的因果关系就是加重呼吸系统和心血管系统疾病(具体体现在增加到医院看病住院的人数,增加急诊看病人数,造成旷工和旷课,减少室外运动的天数);肺部疾病,降低肺部功能;哮喘病发作;和一些心血管病,例如突发性心脏病,心率失常。对微粒特别敏感的人群包括:老年人,有心脏病和肺部疾病的患者,和儿童。
     微粒的来源包括各种各样的燃烧过程(例如汽车发动机,发电厂,燃烧木头等等),和一些工厂加工过程。微粒在2.5和10之间被称为粗加工的产物,其来源包括研磨加工,还有包括道路上产生的尘埃。
     在1997年,美国环保署就首次制定了年度,和24小时国家环境空气质量标准来监测PM2.5。在2006年,美国环保署修订了24小时监控PM2.5的条例。有关更多的信息和相关的实施措施在政府环保署网站公布于众。
    The term "particulate matter" (PM) includes both solid particles and liquid droplets found in air. Many manmade and natural sources emit PM directly or emit other pollutants that react in the atmosphere to form PM. These solid and liquid particles come in a wide range of sizes.
     Particles less than 10 micrometers in diameter (PM10) pose a health concern because they can be inhaled into and accumulate in the respiratory system. Particles less than 2.5 micrometers in diameter (PM2.5) are referred to as "fine" particles and are believed to pose the largest health risks. Because of their small size (less than one-seventh the average width of a human hair), fine particles can lodge deeply into the lungs.
     Health studies have shown a significant association between exposure to fine particles and premature mortality. Other important effects include aggravation of respiratory and cardiovascular disease (as indicated by increased hospital admissions, emergency room visits, absences from school or work, and restricted activity days), lung disease, decreased lung function, asthma attacks, and certain cardiovascular problems such as heart attacks and cardiac arrhythmia. Individuals particularly sensitive to fine particle exposure include older adults, people with heart and lung disease, and children.
     Sources of fine particles include all types of combustion activities (motor vehicles, power plants, wood burning, etc.) and certain industrial processes. Particles with diameters between 2.5 and 10 micrometers are referred to as "coarse." Sources of coarse particles include crushing or grinding operations, and dust from paved or unpaved roads.
    In 1997, EPA established annual and 24-hour NAAQS for PM2.5 for the first time. In 2006, EPA revised the 24-hour NAAQS for PM2.5. Additional information on these standards and related implementation activities is provided here.

     森井牌高效专业净化器系列均具备医疗级别HEPA能有效过滤直径为0.3微米(头发直径的1/200)以上的微粒去除效率可达到99.99%以上。

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