RADIOACTIVE WATER POOL

A surface or underwater nuclear detonation creates a radioactive water pool in the area of the detonation. This pool expands outward rapidly from SZ, for about 2 minutes, then continues to expand more slowly. At 30 minutes, dispersion of the pool and radioactive decay will have reduced the hazard to one of tactical

insignificance. During the early expansion phase of this pool, a dose rate of several thousand rad/hr may exist at the water surface.

PERSONNEL INJURIES

Injuries to personnel can be caused by the blast, by thermal radiation, and by nuclear radiation. Personnel receiving these injuries are generally described as combat ineffective (CIs) or fatalities. A CI is defined as anyone unable to man a battle station. The potential for a given nuclear weapon to produce fatalities is fairly well known. The potential for CIs is not well known. We have no satisfactory method for estimating

the extent to which combined injuries relate to the number of CIs. Therefore, for each weapon effect capable of injuring an individual, the non-injury and fatal levels are stated. Only the estimates of the degree of injury are stated for the levels between these injury categories.

Air Blast Injury

Bodily displacement is the dominant cause of air blast casualties for personnel in the open. Personnel can be picked up and thrown by the blast. They receive their injuries upon landing. The extent of the injuries will depend upon the velocity of the body's movement, the nature of the object with which the body collides, and the nature of impact, whether glancing or solid.

Primary blast effects are associated with injuries from static overpressure. Eardrums can rupture at about 5 psi, lung injuries occur at approximately 15 psi, and fatalities begin at 30 psi.

Personnel standing in the open will be picked up and thrown by gust winds at overpressures of approximately 6 psi. Personnel prone in the open will be picked up and thrown at overpressures of approximately 12 psi.

Underwater Shock Injury

Underwater shock produces injury among topside and below-deck personnel by the rapid upward movement of the deck. Table 8-1 shows the estimated peak vertical velocity, in feet per second, that will produce certain injuries from underwater shock. It should be noted that the peak vertical velocities are the same as those required to produce damage to the ship.

Table 8-1.-Combat Ineffective from Underwater Shock

harmful effects on the body. It should be avoided whenever possible, without interfering with military operations.

FACTORS INFLUENCING RADIATION INJURIES.- The biological injury to an individual who has received nuclear radiation will depend on many factors. Some of these factors are discussed in the following material. (All radiation doses referred to in this book are due to external whole-body exposures to penetrating radiation.)

Thermal Radiation Injury

Thermal radiation can cause burn injuries directly when the skin absorbs radiant energy. It can also cause burn injuries indirectly as a result of fires started by the radiation. Direct burns are often called flash burns; they are produced by the flash of thermal radiation from the fireball. The indirect, or secondary, burns are called flame burns. These burns are like the skin burns that are caused by any large fire, no matter what its origin.

Because thermal radiation can burn the retina of the eye, it can cause permanent eye damage to personnel looking directly at the burst. For example, a 1-megaton burst 25 miles high could produce retinal burns out to the horizon on clear nights. A more frequent occurrence is the temporary loss of visual acuity (flash blindness or dazzle). This is caused by exposure to the extreme brightness of a nuclear burst, particularly at night when the eyes have adapted to the dark. This may happen regardless of the direction you are facing. Flash blindness or dazzle occurs at ranges beyond those for retinal burns. Little data on the ranges at which flash blindness will occur is available.

Nuclear-Radiation Injury

Radiological hazards described in this section are those which might be of significance for the military effectiveness of naval personnel in combat operations. Injuries to personnel can be caused by exposure to initial or residual radiation or a combination of the two. Unlike injuries from other weapon effects, nuclear ionizing radiation injuries may not become evident immediately unless a high enough dose is received. Nuclear radiation, even in very small doses, has some

Radiation dose received

Partial or whole-body exposure

Period over which the dose is received

Variations in the body's resistance to radiation injury, including those due to physical condition, sex, and age

Previous radiation exposure

Presence or absence of other injuries

Periods of recuperation between periods of radiological exposure

The time required for a previously unexposed individual in good health to get sick or die after exposure will vary. It depends primarily on the total dose received, the period of time over which it was received, and variations in individual physical makeup. Some individuals have greater resistance to radiation injury than others have, and some may have had partial body shielding when exposed. For those personnel, a larger dose is required to produce a given biological effect. Individuals previously exposed may require less radiation to make them combat ineffective than those who were not previously exposed. The human body can repair some of the radiation injury but not all of it. Generally, a given dose received in a short period of time will be more harmful than the same dose received over a longer period of time. For practical purposes, the types of radiation exposures are as follows:

. Acute. Those in which doses are received in a short time, normally less than 24 hours, as a result of exposure to initial radiation, base surge, or fallout, or combinations thereof.

_{. Protracted. Those in which doses are} for both acute (less than 24 hours) and protracted received over a longer period of time, normally (over 24 hours) doses. Table 8-3 describes greater than 24 hours, as a result of exposure to ^{symptoms and probable effects for various} fallout. exposures.

Table 8-2 outlines the effects of radiological