Hampson Neil B, Courtney Todd G, Holm James R
Center for Hyperbaric Medicine, Virginia Mason Medical Center, Seattle, WA 98101, USA.
J Emerg Med. 2012 Apr;42(4):478-82. doi: 10.1016/j.jemermed.2011.03.015. Epub 2011 May 4.
Numerous states and localities have recently passed legislation mandating the installation and use of residential carbon monoxide (CO) detectors/alarms. Interestingly, there seems to be confusion about the optimal placement, if any, of CO alarms inside the home.
It was the goal of this study to demonstrate the behavior of CO in air and to help provide a data-based recommendation for CO alarm placement.
CO was calculated to be slightly lighter than air. An 8-foot-tall airtight Plexiglas chamber was constructed and CO monitors placed within at the top, middle, and bottom. CO test gas (15 L, 3000 parts per million) was infused at each of the three heights in different trials and CO levels measured over time.
Contrary to a significant amount of public opinion, CO did not layer on the floor, float at the middle of the chamber, or rise to the top. In each case, the levels of CO equalized throughout the test chamber. It took longer to equalize when CO was infused at the top of the chamber than the bottom, but levels always became identical with time.
As would have been predicted by the Second Law of Thermodynamics, CO infused anywhere within the chamber diffused until it was of equal concentration throughout. Mixing would be even faster in the home environment, with drafts due to motion or temperature. It would be reasonable to place a residential CO alarm at any height within the room.
最近，许多州和地方通过了立法，强制要求安装和使用家用一氧化碳（CO）探测器/报警器。有趣的是，对于室内一氧化碳报警器的最佳放置位置（如果有最佳位置的话）似乎存在困惑。
本研究的目的是展示一氧化碳在空气中的行为，并为一氧化碳报警器的放置提供基于数据的建议。
经计算，一氧化碳比空气略轻。构建了一个8英尺高的气密有机玻璃室，并在顶部、中部和底部放置一氧化碳监测器。在不同试验中，在三个高度分别注入一氧化碳测试气体（15升，百万分之3000），并随时间测量一氧化碳水平。
与大量公众观点相反，一氧化碳并未聚集在地板上、漂浮在室中部或上升到顶部。在每种情况下，测试室内的一氧化碳水平都会达到均衡。当在室顶部注入一氧化碳时，达到均衡所需的时间比在底部注入时更长，但随着时间推移，水平最终总是会变得相同。
正如热力学第二定律所预测的那样，在室内任何位置注入的一氧化碳都会扩散，直到整个室内浓度相等。在家庭环境中，由于人员活动或温度导致的气流会使混合速度更快。在房间内的任何高度放置家用一氧化碳报警器都是合理的。
