How Radiation to be Measured?

Radiation is measured in two units - rads and rems. A rad stands for "radiation absorbed dose" and measures the amount of energy that is actually absorbed per unit mass. A rem stands for "roentgen equivalent man" and is a unit that measures the absorbed dose in human tissue and relates it to the effective damage done to your tissue. It is significant because not all radiation has the same biological effect. The radioactivity of a source is usually measured in how many rads or rems you would receive per hour; a geiger counter normally measures radiation in millirems per hour (mr/hr).

For more details, you could visit radiation protection.

Tungsten Alloy Tube for Radiation Shielding

Tungsten Alloy are more useful for detecting beta particles and gammas. Most counters cannot detect alpha particles. Remember that alpha particles are easily shielded. For this reason, tungsten alloy tube has to be made with a special window, or else the window itself will block the alpha particles and they won't be detected. Secondly, the counter must be held steady for several seconds at the same distance in order for us to obtain a good reading. Moving the counter around will change the number of particles that enter the tube; so make sure that you hold the tube the same distance from each object that you are trying to measure, or else your results will not be accurate. A third disadvantage of a Geiger counter is that it cannot measure very high amounts of radiation; in fact, the machine can be damaged if you expose it to an extremely high radiation, but that is unlikely in our case.

Different Radiations

Here are many different radiations in our life:

An alpha particle (a) consists of two protons and two neutrons (a helium nucleus). It has a relatively large mass and a positive charge. Alpha particles are easily shielded by a piece of paper or human skin. Therefore, health effects of alpha exposure occur only when the particles are inhaled, ingested, or enter the body through a cut in the skin. More serious would be a material that is radioactive (a emitter) that is ingested into the body. The a particles emitted inside the body, for example in bone marrow, can be exceedingly dangerous.

Beta particles (b) are fast electrons produced following nuclear decay of certain radioactive materials. The amount of energy (speed) that a beta particle contains determines its penetrating capacity. Six millimeters of aluminum are needed to stop most b particles.

Gamma rays (g), an electromagnetic wave, are similar in form to visible light and radio waves. However, gamma waves are very energetic and have a far shorter wavelength. Gamma rays are produced from radioactive decay, in nuclear reactions, and in fission. Gamma rays are dangerous because they have great penetrating ability. Several millimeters of lead are needed to stop gamma rays.

Therefore, radiation protection is more and more important, for more details, you should visit radiation protection.

How Does Lead Absorb Radiation Like X-rays and Gamma Rays?

The reason that lead is a good choice is because it’s a very dense substance, because dense substances can get in the way of the radiation and soak it up.  And the denser something is the more atoms, and in the case of things like x-rays and gamma rays the more electrons, there are to potentially interact with that ray as it goes through and stop it.

So, if you look at the density of lead; lead weighs something like 11 grams per centimeter cubed.  Iron, on the other hand, is only seven.  So in other words, you can get lots and lots of shielding with lead for much less space than if you use, say iron or concrete, which doesnt have the same density, although both could soak up x-rays in the same way.

However, as tungsten alloy material is more than 60% denser than lead, and it's not of any toxic, tungsten alloy material is widely used for shielding of X-rays and gamma rays. For more details, you could visit tungsten alloy radiation shielding.