8.6.6A rea 6. Freshwater Immersion
Wastewaters are also ap arto ft his area. Includeda re all areas that remain
underwater for periods longer than af ew hours at at ime. Potable and
nonpotablew ater,s anitarys ewage,a nd industrialw aste liquids are
all included.
If the systems recommended are to be used as atank lining material, it is
important that the applicationbedone by experiencedworkers. In addition,
if the coating to be applied is to be in contact with potable water,i ti s
important that the material selected meets the necessary standards and is
approved for use by the local health department.Two coats of epoxy (system
Di nT able 8.5) is frequently used in this service.
Recommended systems areFof Table 8.4 and A, D, E, and FofT able 8.5.
8.6.7A rea 7. Saltwater Immersion
Areas that remain under water in ac oastal environmento ri ndustrial
area or that are constantlysubjected to flowing salt or brine laden water are
included in this category.Because of the increased rate of corrosion, athird
coat may be added to system FofT able 8.5 and systems Aand EofT able 8.5
as additional protection againstthis more severe corrosion.
System Do fT able 8.4 and systems A, E, and Fo fT able 8.5 are recommendedf or this service.
8.6.8A rea 8. AcidicChemical Exposure (pH 2.0–5.0)
In the chemicalp rocess industries, this is oneo ft he most severe
environments to be encountered. When repainting, it is important that all
surfaces are clean of any chemical residue. Inorganic zinc and zinc filled
coatings aren ot recommended for application in this area.
The system selected will be dependent upon the quality of surface
preparation, length of chemical exposure, and housekeeping procedures.
Decreased cleanup and longer exposure timesr equireamore chemical
resistant coating system such as system Ii nT able 8.4.
Other recommendations for this area include systems D, G, and Ii n
Table 8.4 and system Bi nT able 8.7.
8.6.9A rea 9. Neutral Chemical Exposure (pH 5.0–10.0)
This is an area that is not subject to direct chemical attack,b ut it may be
subject to fumes, spillage, or splash. Under these conditions, more protection
is required than willbeprovided by astandard painting system. This would
include such locations as clean rooms, packaging areas, hallways, enclosed
processa reas,i nstrument rooms, electricall oadc enters,a nd other
similar locations.
Al ist of potential chemicals that may contact the coating aids in the
coating selection. Knowledge of cleanup procedures willalso prove helpful.
Corrosion of Linings and Coatings
506
CAT8247—CHAPTER 8—17/10/2006—14:20—SRIDHAR—XML MODEL B–pp. 487–507
Wastewaters are also ap arto ft his area. Includeda re all areas that remain
underwater for periods longer than af ew hours at at ime. Potable and
nonpotablew ater,s anitarys ewage,a nd industrialw aste liquids are
all included.
If the systems recommended are to be used as atank lining material, it is
important that the applicationbedone by experiencedworkers. In addition,
if the coating to be applied is to be in contact with potable water,i ti s
important that the material selected meets the necessary standards and is
approved for use by the local health department.Two coats of epoxy (system
Di nT able 8.5) is frequently used in this service.
Recommended systems areFof Table 8.4 and A, D, E, and FofT able 8.5.
8.6.7A rea 7. Saltwater Immersion
Areas that remain under water in ac oastal environmento ri ndustrial
area or that are constantlysubjected to flowing salt or brine laden water are
included in this category.Because of the increased rate of corrosion, athird
coat may be added to system FofT able 8.5 and systems Aand EofT able 8.5
as additional protection againstthis more severe corrosion.
System Do fT able 8.4 and systems A, E, and Fo fT able 8.5 are recommendedf or this service.
8.6.8A rea 8. AcidicChemical Exposure (pH 2.0–5.0)
In the chemicalp rocess industries, this is oneo ft he most severe
environments to be encountered. When repainting, it is important that all
surfaces are clean of any chemical residue. Inorganic zinc and zinc filled
coatings aren ot recommended for application in this area.
The system selected will be dependent upon the quality of surface
preparation, length of chemical exposure, and housekeeping procedures.
Decreased cleanup and longer exposure timesr equireamore chemical
resistant coating system such as system Ii nT able 8.4.
Other recommendations for this area include systems D, G, and Ii n
Table 8.4 and system Bi nT able 8.7.
8.6.9A rea 9. Neutral Chemical Exposure (pH 5.0–10.0)
This is an area that is not subject to direct chemical attack,b ut it may be
subject to fumes, spillage, or splash. Under these conditions, more protection
is required than willbeprovided by astandard painting system. This would
include such locations as clean rooms, packaging areas, hallways, enclosed
processa reas,i nstrument rooms, electricall oadc enters,a nd other
similar locations.
Al ist of potential chemicals that may contact the coating aids in the
coating selection. Knowledge of cleanup procedures willalso prove helpful.
Corrosion of Linings and Coatings
506
CAT8247—CHAPTER 8—17/10/2006—14:20—SRIDHAR—XML MODEL B–pp. 487–507