究竟輻射會不會自動消散?

You have to differentiate between the [radiation] from mobile phones, base stations with that from X-ray machines. The first two are [non-ionizing radiation] which doesn't cause the formation of charged particles in air. The last one, X-rays, is a type of [ionizing radiation] because it will cause air to become ionized.
Non-ionizing radiation (electromagnetic waves used in mobile phones):
There is at present no conclusive scientific evidence that exposure to non-ionizing radiation like radiofrequency (RF) radio waves used in mobile phones has adverse health effect to human. RF radio waves only causes heating effect to the body, which might lead to an elevation of body temprature but is usually restored to normal rapidly by increase of body circulation.
Ionizing radiation ( X-rays or gamma rays):
This type of radiation, due to their ionization power, can cause damage to cells and the DNA molecules. This will lead to stochastic effect like the development of cancer, and deterministic effect like cataract or permanent sterity. However, the risk is usually proportional to the radiation dose recieved. For dose below 100 mSv (milliSievert, which is a unit for measuring dose), there is bound to be no observable health effects.
You don't have to worry if you stay next to an X-ray room. Every X-ray room in Hong Kong has been assessed to ensure that the shielding incorporated therein satisfies the requirement by law (which is the Radiation Ordinance, Cap.303, Laws of Hong Kong). Any person who stays next to the X-ray room wouldn't receive any radiation dose that is of significant effect in causing any harm to the body.

樓主指的輻射大概是指電磁波吧
樓主請放心，照射到人體中的輻射是不會被儲存的
不論是人體，普遍來說我們身邊都不會有東西能儲存輻射

所以被輻射照射所受到的傷害只視乎被照射時所受到的輻射強度和劑量
電磁波的波長愈短，穿透性就愈強，因此Ｘ光才能用於透視人體
一般來說平日用的手機所發射的電磁波是無線電波，它的波長比可見光要長多了
雖然周遭的人都在用手機，但對人體所構成傷害的速率連照一次日光浴也比不上
人體會自我修復，樓主不用擔心一些微不足道的傷害

至於Ｘ射線的波長十分短，略大於0.5納米
樓主也請放心，醫生們都知道Ｘ射線對人體的影響
他們應該不會經常叫你去照Ｘ光的
因為Ｘ光能破壞細胞的結構、改變ＤＮＡ，從而產生癌細胞
所以一般照完一次Ｘ光之後需要等幾個月後才能照第二次
樓主請相信自己的白血球，牠們不會讓你因為照一次Ｘ光便患上癌症

最後，住在發射站附近，環境中的無線電波的劑量應該較高
但不會對身體構成大威脅
目前科學家們都未完全了解手機和發電站的無線電波會對人體構成怎樣的影響
正如剛才所說，影響不大。

其實輻射有分好多種嫁~只要係溫度高於絕對零度ge環境都有輻射嫁!(紅外線)
每一種ge放射原ge半衰期都不同(根據該放射原原子的質量和穩定性等而定)
so:
-----------理論上,輻射並不會自動消散! 只會自動地減弱!(因所有東西都會趨向穩定,而它們每次進行衰變時該輻射強度只會減半,並不會消失!X除2再除2除2都不會=0)
-----------時間要多久?又或者吸多久才會对人體有害?-跟本不能答到你~
因為每種輻射的強度,人體所受到的輻射劑量,時間等都會有影響嫁~!

輻射係會自己消散
因為一般物質都會吸收輻射而轉化為熱能

不過時間同量就唔同既輻射有唔同