Preservative selection criteria.

TM 38-260

and 4. The exact nature of corrosion and how to prevent all of it is not known. Most efforts must, at present, be content

merely with slowing down the process. However, several forms of corrosion have been identified and numerous

corrosion preventive processes have been developed.

b. Preservative selection criteria. To choose the type of preservative to be applied to a specific item of IPE, a

number of factors must be considered: 1) The physical characteristics of the item to be preserved. The composition,

surface, finish, complexity of construction, size, and shape must all be evaluated before a preservative is selected. 2)

The characteristics of the preservative which must be evaluated. Some preservatives become hard when they dry and

are difficult to remove. Some are thin and drain off too rapidly under high temperatures. 3) The degree of protection

desired. If the item is to be used within a relatively short period of time, only a light temporary preservative is necessary,

but if the item is to be shipped overseas, or must remain in storage for several years, then a more persistent coating is

demanded. 4) The requirements of the user must be considered. If it is necessary to spend excessive hours attempting

to remove hard-drying and hard-setting preservative without adequate cleaning equipment, the cost could be prohibitive.

c. P-type preservatives.

Preservative materials that are most commonly used on IPE, and their

recommended use are listed in table 2-1.

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