MIL-HDBK-1110
Table 2
Problems Encountered With Low-VOC Coatings
Generic Coating Type
Problems Observed
Oil-based
Longer drying time
Residual tack or softness
Poor leveling
Wrinkling
Two-component epoxies
Reduced pot life
Shortened drying time
Settling
Sagging
Poor application properties
Polyurethanes
Reduced pot life
Inability to apply thin films
Reduced gloss
3.2.2
Application Issues. In some regions of the country,
VOC emissions into the air have been further reduced by
regulations restricting the methods of application of coatings to
those with a minimum transfer efficiency of 65 percent. Transfer
efficiency is defined as the percent of the mass or volume of
solid coating that is actually deposited on the item being
coated, as shown in the following formulas:
Transfer Efficiency
(Percent)
= Mass of Solid Coating on Item x 100
Mass of Solid Coating Consumed
Transfer Efficiency
(Percent)
= Volume of Solid Coating on Item x 100
Volume of Solid Coating Consumed
3.2.3
Toxic Solvents. Paints and coatings often contain
solvents that are toxic at some level. While a person can
withstand nominal quantities of most of these ingredients for
relatively short periods of time, continuous or overexposure to
them may have harmful effects. The potential severity of hazards
is greatly magnified when operations are performed in enclosed or
confined spaces where toxic solvent concentrations can quickly
build up to levels which could produce disability and death. The
threshold limit values (TLV) for several commonly used paint and
cleaning solvents are given in Table 3. The TLV is a measure of
the maximum concentration of solvent vapor in the air which can
be tolerated during an 8-hour working day. Since these
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