多亏了博彩平台推荐的新研究, scientists see the impact of flushing the toilet in a whole new light—和 now, 世界也可以.

使用亮绿色激光和摄像设备, a team of CU Boulder engineers ran an experiment to reveal how tiny water droplets, 肉眼看不见的, 是迅速弹射到空中时没有盖子的吗, 公共厕所的马桶冲水了. 现在发表于 科学报告, it is the first study to directly visualize the resulting aerosol plume 和 measure the speed 和 spread of particles within it. 

These aerosolized particles are known to transport pathogens 和 could pose an exposure risk to public bathroom patrons. 然而, this vivid visualization of potential exposure to disease also provides a methodology to help reduce it.

“If it's something you can't see, it's easy to pretend it doesn't exist. 但是一旦你看了这些视频, 你再也不会以同样的方式思考马桶冲水了,” 约翰Crimaldi, lead author on the study 和 professor of civil, environmental, 和 architectural engineering. “通过制作这个过程的戏剧性视觉图像, 博彩平台推荐的研究可以在公共卫生信息传递方面发挥重要作用.”

Researchers have known for over 60 years that when a toilet is flushed, 固体和液体按设计下降, 但小, 看不见的颗粒也被释放到空气中. Previous studies have used scientific instruments to detect the presence of these airborne particles above flushed toilets 和 shown that larger ones can l和 on surrounding surfaces, 但直到现在, no one understood what these plumes looked like or how the particles got there. 

Underst和ing the trajectories 和 velocities of these particles—which can transport pathogens such as E. 杆菌、C. 难相处的, noroviruses 和 adenoviruses—is important for mitigating exposure risk through disinfection 和 ventilation strategies, 或者改进厕所和冲水设计. While the virus that causes COVID-19 (SARS-CoV-2) is present in human waste, there is not currently conclusive evidence that it spreads efficiently through toilet aerosols.

“人们都知道厕所会排放气溶胶, 但他们还没能看到它们,克里马尔迪说. “We show that this thing is a much more energetic 和 rapidly spreading plume than even the people who knew about this understood.” 

The study found that these airborne particles shoot out quickly, at speeds of 6.6英尺(2米)每秒，达到4.9英尺(1英尺).5米)以上的厕所在8秒内. While the largest droplets tend to settle onto surfaces within seconds, 较小的颗粒(小于5微米的气溶胶), or one-millionth of a meter) can remain suspended in the air for minutes or longer. 

It’s not only their own waste that bathroom patrons have to worry about. Many other studies have shown that pathogens can persist in the bowl for dozens of flushes, 增加潜在的暴露风险.   

“这种马桶的目的是有效地清除马桶里的废物, 但它也在做相反的事情, 它向上喷射了很多内容物,克里马尔迪说. “Our lab has created a methodology that provides a foundation for improving 和 mitigating this problem.”

不是浪费时间 

克里马尔迪负责 生态流体动力学实验室 在博彩平台推荐, 哪家公司专门使用激光仪器, 染料和巨大的液体罐来研究一切 气味是如何到达博彩平台推荐的鼻孔的 化学物质如何在动荡的水体中运动. The idea to use the lab’s technology to track what happens in the air after a toilet is flushed was one of convenience, 好奇心和环境. 

去年6月，在一个空闲的星期里，教授们 卡尔·林登 和 马克埃尔南德斯 环境工程专业, 和 several graduate students from Crimaldi’s lab joined him to set up 和 run the experiment. 亚伦真的, 这项研究的第二作者，克里马尔迪实验室的助理研究员, was instrumental in running 和 recording the laser-based measurements for the study. 

他们使用了两束激光:一束连续照射在马桶上方和上面, 而另一个则在同一区域发出快速的光脉冲. The constant laser revealed where in space the airborne particles were, 而脉冲激光可以测量它们的速度和方向. 同时，两台相机拍摄了高分辨率图像. 

The toilet itself was the same kind commonly seen in North American public restrooms: a lid-less unit accompanied by a cylindrical flushing mechanism—whether manual or automatic—that sticks up from the back near the wall, 称为冲水阀式阀门. 崭新、干净的厕所里只装了自来水. 

They knew that this spur-of-the-moment experiment might be a waste of time, 而是, 这项研究引起了轰动. 

“博彩平台推荐原本预计这些气溶胶颗粒会漂浮起来, 但他们像火箭一样出现了,克里马尔迪说.

精力充沛, airborne water particles headed mostly upwards 和 backwards towards the rear wall, 但他们的行动是不可预测的. 烟雾也上升到了实验室的天花板上, 而且无处可去, 从墙上向外移动，向前伸展, 进入房间. 

The experimental setup did not include any solid waste or toilet paper in the bowl, 没有隔间，也没有人走动. These real-life variables could all exacerbate the problem, said Crimaldi. 

They also measured the airborne particles with an optical particle counter, a device that sucks a sample of air in through a small tube 和 shines a light on it, 让它能够计数和测量粒子. 更小的颗粒不仅在空气中漂浮的时间更长, but can escape nose hairs 和 reach deeper into one’s lungs—making them more hazardous to human health—so knowing how many particles 和 what size they are was also important. 

虽然这些结果可能令人不安, the study provides experts in plumbing 和 public health with a consistent way to test improved plumbing design 和 disinfection 和 ventilation strategies, 以减少在公共厕所接触病原体的风险.

“None of those improvements can be done effectively without knowing how the aerosol plume develops 和 how it's moving,克里马尔迪说. “能够看到这种看不见的羽流是一个改变游戏规则的人.”

本出版物的其他作者包括:亚伦真的, 卡尔·林登, 马克埃尔南德斯, 拉尔斯·拉森和安娜·保罗是民政部的, 环境, 及建筑工程.