铅的原子序数是82，是自然界中原子序数比较高的物质。当然阻挡核辐射的能力比较强。比铅更高的物质阻挡能力会更强。但可惜，这些物质在地球上都是稀有物质，造价相对昂贵(比如原子序数为79的金，原子序数为83的铋），更头痛的是，这些物质自身一般就具有放射性。当然不如用铅来阻挡核辐射划算。
The atomic number of lead is 82, which is the substance with higher atomic number in nature. Of course, the ability to block nuclear radiation is relatively strong. Higher material barrier than lead will be stronger. Unfortunately, these substances are rare on earth, which are relatively expensive (for example, gold with atomic number of 79 and bismuth with atomic number of 83). What's more, they are generally radioactive. Of course, it's better to use lead to block nuclear radiation.
你清楚为什么铅板能够防辐射吗?
Do you know why lead plates are radiation proof?
由于铅板密度高，使得铅板颗粒之间的缝隙非常小，小于紫外外光谱长度，即小于辐射产生的光谱长度，这样辐射的波长就通过不了铅板，所以就能隔离辐射。
Because of the high density of the lead plate, the gap between the lead plate particles is very small, which is less than the length of the UV spectrum, that is, the length of the spectrum generated by the radiation, so the radiation wavelength can not pass the lead plate, so the radiation can be isolated.
1）有的说辐射是释ww.zxsxfh.com
1) Some say that radiation is emission ww.zxsxfh.com

2）各种可见光，有原光，有原光合成的各种复色光，那么紫外外光谱，也会和各种可见光合成多种共存的电磁波。紫外线对人体产生的伤害，我们说是太阳辐射的电磁波，同样核辐射产生的伤害，是紫外外线，即也是电磁波，而不是粒子流。
2) All kinds of visible light, including the original light, and all kinds of polychromatic light synthesized by the original light, then the ultraviolet spectrum will also synthesize a variety of coexisting electromagnetic waves with all kinds of visible light. The damage caused by ultraviolet radiation to human body is the electromagnetic wave of solar radiation. The same damage caused by nuclear radiation is the ultraviolet line, which is also the electromagnetic wave, not the particle flow.