CHAPTER 8

RADIOLOGICAL EFFECTS AND COUNTERMEASURES

As a Damage Controlman, you will be assigned to a repair party during general quarters. There you will take part in CBR countermeasures to limit the effects of a CBR attack. To help you carry out your duties, you should know the types of nuclear bursts and their effects. You will need to evaluate the amount of contamination caused by the nuclear burst and how much radiation you

absorbed. Therefore, you will need to know how to operate and read the various personnel dosimeters and radiac monitoring instruments aboard ship. In addition, you will need to know your duties on a monitoring and survey party. We will discuss these items and the protection that various materials will give you against a nuclear burst.

For more basic information on CBR defense,

consult the appropriate References listed in the Bibliography for Advancement Study, NAVED-TRA 10052. For more comprehensive and detailed information, consult chapters 70 and 470 of the Naval Ships' Technical Manual and COMNAV-SURFLANTINST 3542.1 B, the Repair Party Manual.

THE ATOM

There are about 100 different simple materials

known as elements. They makeup every substance around us. Among the common elements are the gases, such as hydrogen, oxygen, and nitrogen; the solid nonmetals, such as carbon, sulfur, and phosphorous; and the metals, such as iron, copper and zinc. The element uranium is normally a solid metal and is used for nuclear energy.

The smallest quantity of any element that

retains the characteristics of that element is the atom. Atoms are made up of even smaller particles known as electrons, protons, and neutrons. The characteristics of an element are

determined by the relative numbers of these smaller particles. The electron is extremely tiny. Its size is only

about 1/1840 the mass of a proton. The electron has a negative electrical charge. The proton has a positive electrical charge. A neutron is composed of a proton and an electron. The neutron has no charge because the equal and opposite charges of the electron and the proton cancel each other.

The structure of an atom resembles a solar system, with the electrons orbiting around the protons and the neutrons clustered tightly in the center, called the nucleus (fig. 8-1). Because the distance between the electrons and the nucleus is so great, the atom is mostly empty space. The number of electrons that orbit the nucleus of a normal atom is equal to the number of protons in the nucleus. Therefore, the electrical charge of the atom is balanced. The number of neutrons in a nucleus can vary from 0 to more than 150.

A process known as fission splits the nucleus of a heavy element into nuclei of lighter elements. In this process, an enormous amount of energy is produced. When this energy is released in a short

Figure 8-1.-Rutherford-Bohr atomic models.

period of time, an enormous explosion takes place. This explosion is what we call a nuclear burst.