Alaska Science Forum

This article is provided as a public service by the Geophysical Institute, University of Alaska Fairbanks, in cooperation with the UAF research community. T. Neil Davis is a seismologist with the Institute.  

Evidence seems to be mounting that ion concentrations in the air do affect how people feel. Further, there is evidence that the new trend toward using computerized equipment in offices may be creating a special problem.

Outdoor air contains about a thousand positive and negative charges (ions) within each cubic centimeter. Cosmic rays coming into the earth from the sun and elsewhere break apart air molecules and thereby create much of the ionization that exists in the air. Since more cosmic rays come in at the high latitudes, the high-latitude air normally has a higher proportion of ionized air molecules or molecular clusters. However, in cities and in confined spaces such as offices, processes take place to reduce the number of ions. One important process is attachment of charge-carrying molecular clusters to pollution particles in the air. When that happens both the ions and the pollution particles tend to be swept out of the air by the electric field that exists naturally near the earth's surface.

The loss of ion concentration is thought to be harmful because it does seem that high ion concentrations do make people feel better--just why, doesn't seem to be clearly understood. High ion concentrations also apparently inhibit bacterial growth and perhaps foster plant growth. The good effects seem to be attributed to high concentrations of negative ions rather than positive ones; generally, the concentration of both types go together, except in small volumes of air perhaps only a few feet across.

Now, a new problem arises according to an article in the August 1981 issue of Mini-Micro Systems, a publication for computer buffs. The problem has to do with CRTs, the cathode ray tubes contained in video terminals and the newfangled typing stations that seem to be sprouting on desktops all over the country. In the Geophysical Institute alone I counted 70 CRTs, not including cathode ray tubes in test equipment.

The electric field caused by the positive static charge that appears on a CRT in normal operation sweeps the nearby air of negative charges, thereby depleting the negative-ion concentration in the immediate vicinity. Apparently when the ion concentration is lowered by this or any other means--air conditioning does it too--workers complain of headaches, lethargy, dizziness and nausea.

One experiment performed in England on 54 individuals at a computer site seems rather convincing. Negative-ion generators were installed, but, unknown to the persons being tested, the generators were not turned on for four weeks. During that period the negative-ion concentration was about 550 per cubic cm. A secret switching on the generators during the next eight weeks of the test raised the ion concentration to 3,500 per cubic cm, several times that found in normal outside air. After the experimenters turned on the ion generators, they found that the tested persons had fewer headaches and other complaints than before. Only five percent then said they had headaches, whereas 20 percent of the workers complained of headaches before the ion generators were turned on. The number reporting dizziness and nausea dropped by more than half, down to less than one percent.

Other English tests indicate that the more complex the task a person tries, the more the individual is affected by negative-ion levels. Also females are more responsive than males to negative-ion depletion or enrichment.

Fraudulent or questionable claims made some years ago about the benefits of ion generators muddy the issue of how important ion concentrations are in air around workers. Consequently, there now probably will have to be overwhelming evidence that ion levels do affect people before widespread attempts are made to ensure that proper levels are maintained. But if that comes to pass, we may see regulations requiring installation of ion generators in rooms where air conditioning and CRTs are used. 

阿拉斯加科学论坛
1981年9月25日
 -------------------------------------------------- 

负离子和电脑
第505号
由汤匙尼尔戴维斯
-------------------------------------------------- 

这篇文章是由提供公共服务，地球物理研究所，阿拉斯加大学费尔班克斯，与uaf研究界合作。
汤匙尼尔戴维斯是一个地震学家与研究所。 
 -------------------------------------------------- 
证据似乎是越来越多离子浓度在空气中做地影响人们的心情。此外，有证据表明，新的趋向采用电脑化设备中或办公室内，可形成一个特殊的问题。

室外的空气中含有约1000正电和负电（离子）每立方厘米。宇宙射线进入地球从太阳和其他地方休息，除了空气分子，从而创造大量的电离存在于空气之中。由于宇宙射线来了，在高纬度地区，高纬度地区的空气通常有较高比例的电离空气分子或分子簇。然而，在城市和在密闭空间内，例如办公室，生产工序，以减少人数离子。其中一个重要的过程，是依恋的电荷进行分子团簇的污染颗粒，在空中。到那个时候，无论是离子和污染颗粒往往被横扫出空气中的电场存在，自然接近地球表面的。

失去离子浓度被认为是有害的，因为它似乎是高离子浓度做，使人们感觉更好-刚才为什么，似乎并没有明确的理解。高离子浓度也明显抑制细菌的生长和促进植物生长。良好效果似乎归因于高浓度的负离子，而不是正面的积习;一般情况下，集中两种相辅相成，除在小册中的空气，或许只有几英尺的跨越。

现在，一个新的问题出现，根据一篇文章，在1981年8月发行的迷你微型系统，出版物，为电脑发烧友。这个问题也与CRT显示器，阴极射线管中所载的视频终端和栖息地起码打字站似乎是萌发于桌上型电脑遍布全国。在地球物理研究所，仅我数70 CRT的，不包括阴极射线管测试设备。

电场引起积极静电荷这似乎是一个对照表，在正常运作，席卷附近空气中的负费，从而消耗负离子浓度在附近。显然，当离子浓度降低，由本或其他任何方式-空调是否太-工人抱怨头痛，嗜睡，头晕和恶心。

其中一个实验中，在英格兰有54人在电脑网站似乎相当有说服力的。负离子发生器安装了，但未知有关人士正在测试，发电机未打开，为四个星期。在此期间，负离子浓度大约是每550立方厘米。一个秘密的开关对发电机，在未来8个星期的试验提出了离子浓度的3500每立方厘米，多次表示，在正常室外空气。之后，实验者打开离子发生器时，他们发现被测者较少头痛及其他投诉比以前。只有5个百分点，然后说，他们头痛，而20 ％的工人抱怨头痛前离子发生器被打开。有多少报告头晕，恶心，下降了一半以上，下降至不到一％ 。

其他英语测试表明，越是复杂的任务，一个人尝试，更是个人的，是受负离子水平。此外，女性的反应比男性来负离子枯竭或浓缩。

欺诈或有疑问的债权取得了一些年前约的好处离子发生器泥泞的问题，是多么重要离子的浓度是在周围的空气工人。因此，现在有可能将要压倒性的证据表明离子水平不影响人们才广泛尝试，以确保适当的水平得以维持。不过，如果说到过去，我们可以看到，规例，规定安装离子发生器在房间空气调节及CRT的使用.