The process of rusting begins at 40% RH. Metal components and equipment tend to rust and corrode during storage, assembly or plant shut down due to moisture in the air. Rust is the result of Iron being exposed to Oxygen. It is the most commonly used name for the chemical compound known as Iron Oxide. Rust is a type of corrosion, meaning that the metal will break down once it is exposed to the chemical process which occurs when it is exposed to the Oxygen.
Using Corrosion resistant coatings on the metal being exposed. There are many different types of coatings which can be used for corrosion control. The most popular substance is paint. There are a variety of rust preventing paints on the market for residential and commercial applications. When painting the exposed material is not a viable option, there are other substances which are known for their ability to make metal corrosion resistant.
Vapor Corrosion Inhibitors are normally gel or liquid formulas which can be sprayed onto metals in order to increase their corrosion resistance. These types of chemicals are best for preventing electronic corrosion in most situations. They do not get sticky, they do not contain waxes. They allow for movement and so offer excellent rust prevention for moving parts.
Other types of corrosion inhibitors are also available. There are thick, tar like formulas that are excellent for non moving part which require significant protection during storage. They form a moisture barrier along the material to prevent water and Oxygen from reaching the surface.
Micro corrosion preventers are excellent for protecting knives, guns and other sporting goods. One popular type of micro corrosion preventer is a cloth made from special materials which, when rubbed against the metal, forms a barrier against Oxygen. This barrier cannot be removed with water or friction. It simply forms a barrier to protect from corrosion.
The most effective way to prevent corrosion and rust is to limit the exposure of susceptible materials to water and humidity. Another option is Moisture/ Humidity control though Dehumidifiers. Bry-Air dehumidifiers effectively control humidity below 40% RH protecting metals parts, equipment and machinery from corrosion. Massive structures such as Bridges benefit by installing Bry-Air Dehumidifiers. These are capable of maintaining dew point as low as -60º C regardless of ambient conditions and thus are ideal for preventing corrosion/rusting.