如今，新一代的廉价便携式装置正在使有针对性的空气质量监测成为可能。美国环境保护署（Environmental Protection Agency）正在美国各地城市对这些装置进行试用，以期能够更准确地说明当地居民所呼吸的空气的质量。以下是这种装置的三个代表。

请坐

下次，当你在华盛顿（Washington）的国家动物园（National Zoo）或是费城（Philadelphia）的国家独立纪念公园(Independence National Park)的长椅上坐下时，它为你提供的将不仅是歇息。

美国环境保护署正在推出一种可以兼作普通长椅使用的空气质量监测装置。作为绿色乡村项目（Village Green Project）的一个组成部分，环保署将在包括芝加哥(Chicago)和堪萨斯城(Kansas City)在内的美国七个城市设置这类高科技试行休息区。

以风能和太阳作动力的每个监测装置都造在长椅内。空气传感器持续不断地测量臭氧气体成分和颗粒物，并将结果通过无线装置传输到网上。

环境保护署的高级研究员罗恩·威廉姆斯(Ron Williams)说: “我们希望把这些监测装置放在离人很近的地方，以便形成互动。人们可以去一个网站查看每分钟更新的滚动信息。“

公民科学家

新泽西州的纽瓦克(Newark, New Jersey)靠近该州最大的垃圾焚烧炉和其他废物处理设施，更不用说这里还纵横交错地遍布着高速公路干线和铁路交通网。居民们自然会担心他们的空气质量。

环境保护署与一个名叫“Ironbound社区公司”(Ironbound Community Corporation)的当地公民团体合作，设计了四个篮球大小的装置，并将其安放在纽瓦克各处。该项目被称为“公民科学空气监测器” (Citizen Science Air Monitor)，它的简单易用的装置由居民义务操作，并且每周被转移到新的地点。

威廉姆斯说：“纽瓦克是此类合作关系的一个试点。我们专门为他们设计制造了只需转动一下钥匙就可以开始运转和收集数据的装置。”

每个装置都能够测量湿度、温度以及直径是人的发丝三十分之一的二氧化氮颗粒物。

开车兜风

长椅和箱形监测装置是固定的。但环境保护署也在洛杉矶（Los Angeles）等几个城市开始试用移动测量方式。他们在车顶安装大型天线，同时配有空气传感和测绘仪器，使监管人员可以测出沿途的污染情况。

目前使用的空气监测方法只能让监管人员采集有限的空气样本，然后在实验室里进行分析，这个过程很耗费时间。而移动监测方法可以在更大范围内采集样本，获得更大量、更翔实的样本，并且作出实时分析。

环境保护署希望移动技术的成本最终会变得更加经济实用，以供能源领域的公司监视突发情况，譬如地下管道的气体泄漏。快速的反应可以让公司能够及时控制影响空气质量的问题，阻止其进一步扩散，从而更加有益于附近社区的安全。


Breathe easy: Air-quality monitoring goes local

Traditionally, air quality has been monitored by expensive, complex devices. These barriers meant that only government agencies and other large organizations could afford to collect this kind of data. Even then, this information reflected the air quality for a broader region, not a specific area.

Now a new generation of inexpensive, portable devices is allowing targeted air quality monitoring. The U.S. Environmental Protection Agency (EPA) is testing these devices in cities across the U.S., creating a better picture of the air residents breathe. Here are three highlights.

Have a seat

The next time you sit on a bench in Washington’s National Zoo or in Philadelphia’s Independence National Park, it might offer you more than a rest.

The EPA is unveiling air quality monitoring devices that double as ordinary benches. Seven cities across the U.S., includingChicago and Kansas City, will host prototypes of these high-tech rest areas as part of the EPA’s Village Green Project.

Powered by wind and solar, each monitoring station is built into the bench structure. Air sensors continuously measure ozone gas components and particulate matter, wirelessly transmitting the results online.

“We wanted to put these monitoring devices into close proximity to people so it could be interactive,” said Ron Williams, a senior researcher with the EPA. “People can go to a website and see a scrolling message for minute-by-minute updates.

Citizen scientists

Newark, New Jersey, is near the state’s largest garbage incinerator and other waste management facilities, not to mention a network of major highways and rail lines that crisscross the area. Naturally, residents are concerned about their air quality.

In partnership with the Ironbound Community Corporation, a local citizens group, the EPA has designed and deployed four basketball-sized devices throughout Newark. The project, known as the Citizen Science Air Monitors, relies on resident volunteers to operate the user-friendly devices, which are moved to new locations weekly.

“Newark is a pilot program for this type of partnership,” Williams said. “We built a specific device for them that begins operating at the turn of a key and starts collecting data.”

Each unit is capable of measuring humidity, temperature and nitrogen dioxide particulates that are 1/30th the diameter of a human hair.

Take a ride

While devices such as benches and box-shaped monitors are stationary, the EPA has piloted a mobile approach in cities such as Los Angeles. Vehicles mounted with a large antenna adorned with air sensory and mapping equipment allow regulators to track pollutants as they drive.

With current methods of air monitoring, regulators can only collect limited air samples that are then analyzed in a laboratory — a time-consuming process. Mobile methods can cast a wider net, yielding larger, more informative samples analyzed in real time.

Ultimately, the EPA hopes mobile technology becomes cost-effective for companies in the energy sector to use for monitoring unexpected problems, such as gas leaks from underground pipes. Quicker responses would let companies contain air quality issues and keep them from spreading, leading to improved safety for nearby communities.