大学英语四级阅读练习及答案
Although many of us may feel air-conditioners bring relief from hot, humid or polluted outside air, they pose many potential health hazards. Much research has looked at how the movement of air inside a closed environment---such as an office building---can spread disease or expose people in the building to harmful chemicals.
One of the more widely publicized dangers is that of Legionnaire’s disease, which was first recognized inthe 1970s. This was found to have affected people in buildings with air-conditioning systems in which warmair pumped out of the system’ cooling towers was somehow sucked back into the air intake (通风口),in mostcases due to poor design. The warm air, filled with bacteria,was combined with cooled, conditioned air andwas then circulated around various parts of the building. Studies showed that even people outside such buildings were at risk if they walked past air exhaust pipes.
Large air-conditioning systems add water to the air they circulate by means of humidifiers (湿度调节器).Inolder systems, the water used for this process is kept in special reservoirs, the bottoms of which providebreeding grounds for bacteria which can find their way into the ventilation (通风)system. The risk to human health from this situation has been highlighted by the fact that the immune systems (免疫系统)of approximately half of workers in air-conditioned office buildings have developed the ability to fight off the organisms found at the bottom of system reservoirs. But chemicals called “biocides”are added to reservoirs to make them germ-free, and they are dangerous in their own right in sufficient quantities, as they often contain compounds strongly linked to cancers.
Finally, it should be pointed out that the artificial climatic environment created by air-conditioners canalso affect us. In a natural environment, whether indoor or outdoor, there are small variations in temperature and humidity. Indeed, the human body has long been accustomed to these normal changges. In an air-conditioned living or working environment, however, body temperatures remain well under37℃, our normal temperature. This leads to a weakened immune system and thus greater exposure to diseases such as colds and flu.
练习题：
Choose correct answers to the question:
1.What do we know about Legionnaire’s disease from the passage?
A.It was the most wid
相关文章
祈求阅读答案2023-06-06 14:53:17
高山流水阅读答案2023-06-12 01:25:30
八年级语文说明文阅读提高题及答案2023-06-13 04:37:43
抬起头来做人阅读答案2023-06-03 16:35:01
紫藤萝瀑布阅读答案十五篇)2023-06-08 09:36:23
看云识天气同步练习阅读答案2023-06-07 15:32:01
上海对外经贸大学和北京交通大学(威海校区)对比哪个好(排名分数线区2024-03-31 16:25:18
河北高考排名237950名物理能上什么大学(能报哪些学校)2024-03-31 16:19:23
山东城市建设职业学院在山东招生人数和招生计划 多少人2024-03-31 16:15:16
上海农林职业技术学院在湖南招生人数和招生计划 多少人2024-03-31 16:12:52
吉林农业科技学院在湖南招生人数和招生计划 多少人2024-03-31 16:09:19
安徽高考多少分可以上云南经贸外事职业学院 招生人数和最低分2024-03-31 16:04:52
出师表和生于忧患,死于安乐比较阅读及答案参考2023-06-08 10:27:07
冬日香山阅读答案三篇2023-06-17 15:15:22
有事喊董三阅读题答案2023-06-01 22:32:08
