This guide provides general information on the description@ selection@ and application of zinc-rich coatings and the selection of topcoats. Zinc-rich primers as referenced in this Guide are broadly defi ned as primers containing high levels of zinc such as SSPC-Paint 20 or SSPC-Paint 29. Zinc-rich coatings are classifi ed as follows: Type IA Inorganic ?C post-cured@ water-borne@ alkalisilicates Type IB Inorganic ?C self-cured@ water-borne@ alkali silicates Type IC Inorganic ?C self-cured@ solvent-borne@ alkyl silicates Type IIA Organic ?C thermoplastic binders Type IIB Organic ?C thermoset binders Zinc-rich coatings@ both topcoated and untopcoated@ have been used successfully in a wide variety of environmental zones. For a detailed breakdown of applicability of various types of zinc-rich coatings in different environmental zones@ see Section 4.1 and Table 1.-