MIL-HDBK-1110
6.7.7
Organic Solvent Washing. Solvent cleaning is used for
removing oil, grease, waxes, and other solvent-soluble matter
from surfaces. VOC rules may prohibit or limit the use of
solvent cleaning. The local environmental and safety office
should be consulted before using or specifying solvent cleaning.
Inorganic compounds, such as chlorides, sulfates, rust, and mill
scale are not removed by solvent cleaning. Solvent cleaning or
detergent or steam washing must precede mechanical cleaning when
oil and grease are present on the surface because mechanical and
blast cleaning methods do not adequately remove organic
contaminants and may spread them over the surface. Before
solvent washing, any soil, cement splatter, or other dry
contaminants must first be removed. The procedure for solvent
washing is to: wet the surface with solvent by spraying or
wiping with rags wet with solvent; wipe the surface with rags;
and make a final rinse with fresh solvent. Fresh solvent must be
used continuously and the rags must be turned and replaced
continuously. Solvents rapidly become contaminated with oils and
grease since they clean by dissolving and diluting contaminants.
Mineral spirits is effective in most solvent cleaning operations.
SSPC SP 1 describes recommended industry practices for cleaning
steel using solvents.
Organic solvents pose health and safety threats and
should not come into contact with the eyes or skin or be used
near sparks or open flames. Table 3-5 lists the flash points
(the lowest temperature at which an ignitable mixture of vapor
and air can form near the surface of the solvent) and relative
toxicity of common solvents. Disposal of solvent must be done in
accordance with governing regulations. Rags must be placed in
fireproof containers after use. Additional safety information is
contained in Section 13.
6.7.8
Power Tool Cleaning. Power tool cleaning can be used
to remove more tightly adhering contaminants and existing paint
than hand tool cleaning. Either electrical or pneumatic power is
used as the energy source. Power tool cleaning is recommended
when deterioration is localized, deterioration is not a serious
problem, or when abrasive blasting is not possible. SSPC SP 3
and SSPC SP 11 describe the use of some of these tools for steel.
In general, power tool cleaning is less economical and more time
consuming than blasting for cleaning large areas. However, power
tools do not leave as much residue or produce as much dust as
abrasive blasting. Also, some power tools are equipped with
vacuum collection devices. Power tools include sanders,
and rotary peeners. Power tools clean by impact or abrasion or
both. Near-white (i.e., rust and paint removed) steel surfaces
with anchor patterns (although different than those achieved in
blast cleaning) can be obtained with some power tools, as
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