PVC fittings are resistant to corrosion and chemical attack from most acids, alkalis, salts, fungi and bacteria. These fittings have a wide variety of uses in the chemical field and industrial plants. Painting is not required for indoor non-exposed installations. For outdoor installation where the piping may be exposed to significant sunlight, we recommend painting; two coats of a white or light-colored, water-base, outdoor latex paint provides added protection.