WASHING
The primary goal of the washing process is to remove all soil from the fabrics being washed. This is done through a series of baths in which the soil is loosened from the fabric, suspended in the water, and rinsed away. There are five baths in the washing cycle- the breaksuds, the flush suds, two rinse baths, and the sour bath. During the first two baths, the two-shot detergent (detergent/ oxygen bleach) removes and loosens the soil so it may be rinsed away. Sour is used in the last rinse cycle to neutralize alkalinity and to decompose any remaining traces still in clothing.

FABRICS
The laundry personnel should be familiar with the different kinds of fabrics. In general most fabrics can be safely laundered in the ship's laundry without causing damage provided they are resistant to the laundry chemicals used. Therefore, it is a good laundry practice to first determine what type of fabric you are washing and take every precaution to prevent damage. It is essential that all laundry personnel know the different kinds of fabrics. To minimize the effects of chemicals on fabrics, classify all clothing according to color, fiber content, and degree of soiling. Wash lightly soiled articles separately from heavily soiled items to minimize redeposition of soil on fabrics, causing them to look gray/ dull. Wash colored fabrics separately from whites to avoid color transference. For maximum washing efficiency, do not exceed load limits of equipment. In the case of synthetics/ blends, washer loads should not exceed three-fourths of the rated capacity to provide for maximum mechanical action, cleaning efficiency, and to avoid wrinkling. Never use hot flushes with supplies before the first bath. In the case of synthetics or synthetic blends, a hot flush with no supplies will soften the fabric and allow soil to penetrate more deeply. Synthetics or synthetic blends do not absorb water, making rinsing easier. The final extract should be consistent with the Navy wash formula. Laundry chemicals should come in contact with fabrics ONLY AFTER appropriate water levels are achieved. The two-shot detergent mentioned earlier is used in washing all shipboard clothing and textile items, including synthetics and synthetic blends, and no other washing chemical should be used in place of them.

TYPES OF SOIL
In general there are four types of soils. Some can be removed during the washing process and some cannot. It is important that you know them so you can decide whether they require special treatment.
CHEMICAL SOLUBLE SOILS
Chemical soluble soils are soluble or readily dissolvable in chemical solvents. Soils of this type include oils, greases, certain waxes, fatty acids (which are mainly body oils), and vegetable, mineral, and animal oils. These soils usually are not soluble in water and may require special treatment.

WATER SOLUBLE SOILS
Water soluble soils are such substances as sugar, starch, gums, salt, flavoring agents, and syrups, as well as a wide variety of substances generally found in such foods and beverages as mustard, catsup, soups, and soft drinks. Per-spiration stains are also included in this category. These types of soils are removed during the normal laundering process.
INSOLUBLE SOILS
Insoluble soils, substances that are not soluble or dissolvable in either water or chemical solvents, are the materials most commonly found in fabrics and constitute the bulk of the soils removed in the laundry. Included are earth, concrete dust, sand, carbon, ashes, lint, hair, cosmetics, and dandruff. These types of soils are usually less visible than oils, greases, or food stains, but they contribute greatly to fabric damage due to fiber abrasion. Most insoluble soils are readily dispersed during the wash cycle, but their complete removal may prove more difficult. Such soils are some-times redeposited on the garments during the laundry process, a condition that can cause "graying" of the fabric.
SPECIAL SOILS
Special soils are insoluble in either water or laundry chemicals. They may be removed partially or entirely using spotting operations. These soils include nail polish, paint, ink, various kinds of adhesives, and so forth. Spotting operations are discussed in the dry-cleaning chapter.

THE WASH WATER
Water is the most important item used in a laundry. Not only is it needed in quantity, but the quality of water used has an important effect on the washing process. At sea, where quantities of suitable wash water are always subject to greater limitations than ashore, you may not always have enough soft water available. To conserve fresh water, you may be required to use seawater. When water comes from clouds as rain or snow, it picks up carbon dioxide gas. As the water seeps through the ground, the carbon dioxide gas dissolves limestone and some other substances, and the water collects calcium and magnesium salts. The salts are in the form of bicarbonates, chlorides, nitrates, and sulfates. The kind and quantity of these substances are determined by the soil the water passes through. Water that contains an appreciable quantity of salts is HARD water. SOFT water is water that has not picked up salts from the earth, or water that has had these substances removed or neutralized. Since seawater contains the concentration of salts, it is the hardest of all wash waters.

TYPES OF HARD WATER
In laundry terminology, hardness in water is the power to kill soap. When soap is added to hard water, the calcium and magnesium salts in the water combine with the soap to form insoluble lime soaps. These soaps then unite (precipitate) in the form of a sticky, insoluble deposit. This reaction kills the soap and makes it useless for washing, and the sticky deposit traps dirt and puts it back on the fabric in the form of scum. If no dirt is present, the scum is white and is seen as a film on the clothes.

There are two types of water hardness:
1. Temporary hardness- Water that contains calcium and magnesium bicarbonates is called temporary hard because these elements can be removed by boiling. Scale on the inside of steam kettles and steam boilers is due to the precipitation of insoluble carbonates as the hard water is boiled.
2. Permanent hardness- Water that contains calcium and magnesium chlorides that are NOT affected by boiling is said to be permanently hard.
Permanent hardness requires special treatment with chemicals or by distillation.